#portable — Public Fediverse posts

An advanced, #AI-powered #smartphone gimbal featuring #Apple #DockKit integration for superior subject #tracking and an all-in-one #portable design. #photography #camera

An advanced, #AI-powered #smartphone gimbal featuring #Apple #DockKit integration for superior subject #tracking and an all-in-one #portable design. #photography #camera

I picked up a Panasonic RQ-L31, a portable tape recorder for $6.99 at thriftshop. It's shaped like a walkman, but it's oriented around voice recording, not listening to music. It has 2 mic levels, powered mic input, no radio, a counter, it's monophonic, but the killer feature, IMO, is "3X REC", which is a 1/3 speed switch which allows you to record 4.5 hours on a 90 minute cassette, probably at something closer to microcassette quality levels. 1/n

#portable #tape #cassette #3XREC #recording

I picked up a Panasonic RQ-L31, a portable tape recorder for $6.99 at thriftshop. It's shaped like a walkman, but it's oriented around voice recording, not listening to music. It has 2 mic levels, powered mic input, no radio, a counter, it's monophonic, but the killer feature, IMO, is "3X REC", which is a 1/3 speed switch which allows you to record 4.5 hours on a 90 minute cassette, probably at something closer to microcassette quality levels. 1/n

#portable #tape #cassette #3XREC #recording

I ended up also doing an ATNO activation of #POTA GB-5740 (with 85 in the log) and also GB-5597 (with 12 in the log) once John M0IDA departed, since the ATNO was on the way home, and the other was on the walk from the car to the forest. #hamradio #portable

I ended up also doing an ATNO activation of #POTA GB-5740 (with 85 in the log) and also GB-5597 (with 12 in the log) once John M0IDA departed, since the ATNO was on the way home, and the other was on the walk from the car to the forest. #hamradio #portable

The #nerd #high has produced another result! A result that barely clears the hurdles for its intended purpose, but a result nonetheless.

https://codeberg.org/tnalpgge/org-hamlog

It has been quite a journey peeling this metaphorical onion. I'd like to think that I learned something about #Emacs #Lisp and #OrgMode along the way.

No test suite so it may decide to do something weird if a mosquito sneezes on the other side of the planet.

Yes, I tried Org export. No, it did not seem well suited to the Cabrillo portion of the task. But reading the #hamradio transceiver was almost trivial with #Hamlib.

I may try to take this for a spin on a casual #AmateurRadio #portable operation. We shall see.

The #nerd #high has produced another result! A result that barely clears the hurdles for its intended purpose, but a result nonetheless.

https://codeberg.org/tnalpgge/org-hamlog

It has been quite a journey peeling this metaphorical onion. I'd like to think that I learned something about #Emacs #Lisp and #OrgMode along the way.

No test suite so it may decide to do something weird if a mosquito sneezes on the other side of the planet.

Yes, I tried Org export. No, it did not seem well suited to the Cabrillo portion of the task. But reading the #hamradio transceiver was almost trivial with #Hamlib.

I may try to take this for a spin on a casual #AmateurRadio #portable operation. We shall see.

A 5-Band, Lazy-L, Linear-Loaded, Ladder Line Antenna (aka the “5B6L”)

About a year ago I mentioned an antenna devised by Peter Waters G3OJV that used a 13 feet (4 m) vertical wire to create a multiband antenna. I used Peter’s idea to create “A Simple, Low Profile, Multiband Antenna for POTA“. The antenna was designed to work on 20m, 17m, 15m, 12m and 10m with the aid of a tuner. But, I discovered a small problem on the 17m band. If we do the elementary calculation for the length of a quarter-wave radiator at the bottom end of the band (18.068 MHz) we find that it works out to be 12.95 ft – just a whisker short of the 13 ft recommended by G3OJV. So why is that a problem?

The problem arises because the antenna uses a 4:1 unun at the feedpoint. Since the 13 ft length is already almost resonant on 17 meters, the 4:1 unun makes the job of the tuner much harder. That did indeed prove to be the case when I tested my derivative in the field. So, I made a small change when designing the new 5B6L antenna – I increased the length to 14 feet (4.2672 meters) – well … not quite true, but that is the underlying principal behind the linear-loaded equivalent.

Here are the calculated lengths of a quarter-wave radiator at the mid-point of each of the five bands of interest:

A 14ft radiator slips nicely in between the 20m and 17m quarter wavelengths and becomes a “random length” on all 5 bands. Nice. But this is a linear-loaded antenna made from ladder line. Linear-loading shortens the required length by around 30%. Fourteen feet, shortened by 30% works out to 9.8 feet (~3 meters). After field adjustments I settled on a length of 9.75 ft (a little less than 3 meters).

Lose the radials!

I wanted this antenna to be what could be loosely described as a random length dipole – two equal lengths of ladder line (each shorted at one end) so that was how it was constructed. Now we have the benefit of versatility. It could be erected as a traditional dipole although with two very short arms it would be tricky to get it up in the air. It could also be erected as a vertical dipole on a support pole about 7 meters (23 feet) tall like my Spiderbeam. But that would make it difficult to orient the coax feedline so that it comes away from the antenna at 90 degrees, as is required to prevent the feedline picking up some of the radiated signal. Perhaps a sloper would work; now that is a very viable solution.

How ‘Bout a Lazy-L?

One of the YouTube channels I follow is “Jim’s Cool Stuff“. In one of his videos Jim suggested using a “Lazy-L” orientation of a vertical simple wire radiator and single raised radial wire. Why? The purpose is to increase the take-off angle. A vertical antenna usually has a very low take-off angle which is great for chasing DX, but what about shorter-range contacts? From my location in Southern Ontario, Canada it is only a short hop down to the north-eastern states in the USA. The US northeast has a very large concentration of amateur radio operators many of which participate in popular activities like POTA. A vertical antenna is likely to send my signal whistling over their heads, or at the very least, be received at a reduced level.

A Lazy-L configuration optimizes radiation to favor short to mid-range contacts by raising the take-off angle to achieve much shorter hops. Does it work? Yes indeed, during test operations I have been able to make contacts, just over the shallow puddle they call Lake Erie, into Pennsylvania, and across Lake Ontario into the state of New York, with quite respectable signal reports for my QRP CW signal.

But what about DX?

Stations on the west coast of the US or western Canada could be considered almost DX – each is thousands of kilometers away. No problem! I said this antenna has versatility. The Lazy-L configuration can be re-oriented to a straightforward regular vertical with a raised counterpoise very easily. In fact the angle at which the radiating element leans can be adjusted to find an optimum at which near-DX and short hop stations all fall within its radiation pattern.

How to Build a 5B6L

The following describes construction of a 5-Band, Linear-Loaded, Ladder Line antenna that can be operated on 20m, 17m, 15m, 12m and 10m with the use of a tuner. Materials needed are:

• Ladder Line. I recommend stranded conductors because this makes the ladder line more flexible than solid copper conductors. Use of the 5B6L as a field portable antenna may stress solid conductors and lead to failures.
• a 4:1 unun. This item can be purchased or you can build your own using twin lead speaker wire (or similar) wound around a type-43 ferrite toroid

Instructions

• Cut two lengths of ladder line each 10 feet (3 meters) long. These may need to be trimmed during testing.
• Connect the two conductors of each piece of ladder line together at one end only.
• At the other end of each piece of ladder line, cut off the end of one of the conductors.
• Strip the insulation from the other conductor – this will be connected to the 4:1 unun.
• Connect each piece of ladder line to the unun.

Erection of the antenna

Attach a coax feedline to the 4:1 unun. A tuner may be inserted at this end if desired. For practical purposes, unless a very long coax is used, the SWR losses in the coax will not be significant so a tuner at the radio end can be used.

Set up your choice of pole, or other support, attach one end of the antenna to the top of the pole. The other end of the sloping radiating element (the feedpoint) should be supported on a short stick.

The other half of the antenna serves as a raised counterpoise and its far end can be supported by, for example, a trekking pole.

The slope angle can be adjusted by simply moving the counterpoise support sticks. See what works best for you. The whole antenna can be quite stealthy. I erected mine on only a 10 feet high pole. Efficiency may be improved by using a taller support but I prefer stealth when operating in public spaces. Tall antennas arouse suspicion!

The end is nigh!

A generous friend donated a lot of ladder line some time ago and I have used all but a few feet of it. Maybe it’s time to experiment with something different. So my next project – take a deep breath – is something I have been writing about in unflattering terms recently – a short, base loaded whip! What? Have I been enjoying too much Scottish champagne? Well, I thought it would be an interesting challenge to see how efficient I could make a short-ish whip antenna with a base-loading coil. A prototype has been constructed and has made contacts in backyard tests (with my helping fingers tapping on the key ). When the design has been completed you will be able to read about here on Ham Radio Outside the Box. Stay tuned.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

A 5-Band, Lazy-L, Linear-Loaded, Ladder Line Antenna (aka the “5B6L”)

About a year ago I mentioned an antenna devised by Peter Waters G3OJV that used a 13 feet (4 m) vertical wire to create a multiband antenna. I used Peter’s idea to create “A Simple, Low Profile, Multiband Antenna for POTA“. The antenna was designed to work on 20m, 17m, 15m, 12m and 10m with the aid of a tuner. But, I discovered a small problem on the 17m band. If we do the elementary calculation for the length of a quarter-wave radiator at the bottom end of the band (18.068 MHz) we find that it works out to be 12.95 ft – just a whisker short of the 13 ft recommended by G3OJV. So why is that a problem?

The problem arises because the antenna uses a 4:1 unun at the feedpoint. Since the 13 ft length is already almost resonant on 17 meters, the 4:1 unun makes the job of the tuner much harder. That did indeed prove to be the case when I tested my derivative in the field. So, I made a small change when designing the new 5B6L antenna – I increased the length to 14 feet (4.2672 meters) – well … not quite true, but that is the underlying principal behind the linear-loaded equivalent.

Here are the calculated lengths of a quarter-wave radiator at the mid-point of each of the five bands of interest:

A 14ft radiator slips nicely in between the 20m and 17m quarter wavelengths and becomes a “random length” on all 5 bands. Nice. But this is a linear-loaded antenna made from ladder line. Linear-loading shortens the required length by around 30%. Fourteen feet, shortened by 30% works out to 9.8 feet (~3 meters). After field adjustments I settled on a length of 9.75 ft (a little less than 3 meters).

Lose the radials!

I wanted this antenna to be what could be loosely described as a random length dipole – two equal lengths of ladder line (each shorted at one end) so that was how it was constructed. Now we have the benefit of versatility. It could be erected as a traditional dipole although with two very short arms it would be tricky to get it up in the air. It could also be erected as a vertical dipole on a support pole about 7 meters (23 feet) tall like my Spiderbeam. But that would make it difficult to orient the coax feedline so that it comes away from the antenna at 90 degrees, as is required to prevent the feedline picking up some of the radiated signal. Perhaps a sloper would work; now that is a very viable solution.

How ‘Bout a Lazy-L?

One of the YouTube channels I follow is “Jim’s Cool Stuff“. In one of his videos Jim suggested using a “Lazy-L” orientation of a vertical simple wire radiator and single raised radial wire. Why? The purpose is to increase the take-off angle. A vertical antenna usually has a very low take-off angle which is great for chasing DX, but what about shorter-range contacts? From my location in Southern Ontario, Canada it is only a short hop down to the north-eastern states in the USA. The US northeast has a very large concentration of amateur radio operators many of which participate in popular activities like POTA. A vertical antenna is likely to send my signal whistling over their heads, or at the very least, be received at a reduced level.

A Lazy-L configuration optimizes radiation to favor short to mid-range contacts by raising the take-off angle to achieve much shorter hops. Does it work? Yes indeed, during test operations I have been able to make contacts, just over the shallow puddle they call Lake Erie, into Pennsylvania, and across Lake Ontario into the state of New York, with quite respectable signal reports for my QRP CW signal.

But what about DX?

Stations on the west coast of the US or western Canada could be considered almost DX – each is thousands of kilometers away. No problem! I said this antenna has versatility. The Lazy-L configuration can be re-oriented to a straightforward regular vertical with a raised counterpoise very easily. In fact the angle at which the radiating element leans can be adjusted to find an optimum at which near-DX and short hop stations all fall within its radiation pattern.

How to Build a 5B6L

The following describes construction of a 5-Band, Linear-Loaded, Ladder Line antenna that can be operated on 20m, 17m, 15m, 12m and 10m with the use of a tuner. Materials needed are:

• Ladder Line. I recommend stranded conductors because this makes the ladder line more flexible than solid copper conductors. Use of the 5B6L as a field portable antenna may stress solid conductors and lead to failures.
• a 4:1 unun. This item can be purchased or you can build your own using twin lead speaker wire (or similar) wound around a type-43 ferrite toroid

Instructions

• Cut two lengths of ladder line each 10 feet (3 meters) long. These may need to be trimmed during testing.
• Connect the two conductors of each piece of ladder line together at one end only.
• At the other end of each piece of ladder line, cut off the end of one of the conductors.
• Strip the insulation from the other conductor – this will be connected to the 4:1 unun.
• Connect each piece of ladder line to the unun.

Erection of the antenna

Attach a coax feedline to the 4:1 unun. A tuner may be inserted at this end if desired. For practical purposes, unless a very long coax is used, the SWR losses in the coax will not be significant so a tuner at the radio end can be used.

Set up your choice of pole, or other support, attach one end of the antenna to the top of the pole. The other end of the sloping radiating element (the feedpoint) should be supported on a short stick.

The other half of the antenna serves as a raised counterpoise and its far end can be supported by, for example, a trekking pole.

The slope angle can be adjusted by simply moving the counterpoise support sticks. See what works best for you. The whole antenna can be quite stealthy. I erected mine on only a 10 feet high pole. Efficiency may be improved by using a taller support but I prefer stealth when operating in public spaces. Tall antennas arouse suspicion!

The end is nigh!

A generous friend donated a lot of ladder line some time ago and I have used all but a few feet of it. Maybe it’s time to experiment with something different. So my next project – take a deep breath – is something I have been writing about in unflattering terms recently – a short, base loaded whip! What? Have I been enjoying too much Scottish champagne? Well, I thought it would be an interesting challenge to see how efficient I could make a short-ish whip antenna with a base-loading coil. A prototype has been constructed and has made contacts in backyard tests (with my helping fingers tapping on the key ). When the design has been completed you will be able to read about here on Ham Radio Outside the Box. Stay tuned.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Self-contained highly-portable Python distributions

https://gregoryszorc.com/docs/python-build-standalone/main/

Comments: https://news.ycombinator.com/item?id=49073942

#HackerNews #Python #Distributions #Portable #Development #Standalone #HackerNews

Self-contained highly-portable Python distributions

https://gregoryszorc.com/docs/python-build-standalone/main/

Comments: https://news.ycombinator.com/item?id=49073942

#HackerNews #Python #Distributions #Portable #Development #Standalone #HackerNews

https://www.alojapan.com/1515243/ghit-fund-invests-approx-jpy-140-million-in-a-portable-rapid-diagnostic-system-for-ebola-disease-in-a-joint-project-between-osaka-metropolitan-university-k-k-dnaform-and-inrb/ GHIT Fund Invests Approx. JPY 140 Million in a Portable Rapid Diagnostic System for Ebola Disease in a Joint Project Between Osaka Metropolitan University, K.K. DNAFORM, and INRB #140 #a #and #Approx #between #Diagnostic #disease #DNAFORM #Ebola #for #Fund #GHIT #in #INRB #Invests #Joint #JPY #KK #metropolitan #million #news #Osaka #OsakaNews #portable #project #Rapid #system #university #大阪 #大阪府 TOKYO, July 23, 2026 /PRNewswire/ — The Global

TechTip #2 (revised): GTU hand capacitance

NB: This is a revised version of TechTips #2 with the addition of further details on how the issue of hand capacitance has been resolved.

The problem: Hand capacitance makes it difficult to accurately adjust the GTU.

The fix: Upon examination of my own GTU it was discovered that the layout had become too complex and the plastic enclosure provided no shield against capacitance between my hand and the RF circuitry. The solution is actually very simple; either re-assemble the GTU inside a metal enclosure, or provide some means of shielding the circuitry from hand capacitance. Since I didn’t have a suitable metal enclosure I elected to do the latter. The entire plastic enclosure was covered with aluminum duct tape. As an additional precaution, the duct tape was electrically connected to the ground binding post to ensure it remains at ground potential.

Did it work? Yes, I am pleased to report that this fix has entirely eliminated the problem. Here is a photo of the shielded GTU (KQ4TQ single inductance version):

The following is the pre-amble to the first version of TechTips #2 (now deleted to avoid confusion).

This is the second in an occasional series of short posts that zero in on details of a specific technical topic in relation to projects here on this blog, which some readers may find helpful.

A few weeks Ham Radio Outside the Box published a description of a “Mini Ground Tuning Unit (GTU)”. The schematic for that device is reproduced below. The design was then simplified with input from HROTB-Labs collaborator Tim KQ4TQ. Tim proposed a single inductance with a value of 3 microhenries (and generously donated a prototype he had built).

I built the revised GTU and performed many experiments in HROTB-Labs outdoor test facility (actually, my backyard). Various types of ground planes were tried, from G4AKC’s capacitance plate at the base of his pedestrian mobile radio trolley, to Faraday cloth (“magic carpet”), to ground radials.

My least favorite was the Faraday cloth. The one I used was about 1 square meter in area. I acknowledge the input of Paul VE3PVB who emphasized the need to maximize the area of the Faraday cloth to improve its efficiency. Two things about Faraday cloth are worth noting: first it has a shiny surface which can be distractingly reflective in bright sunshine. Second, it is often referred to as “magic carpet” – a very appropriate term since it has a tendency to fly in even a mild wind. Matt finish paint and a bag of rocks fixes both issues.

I settled on a set of 8 short radials (each 7 feet, or 2 meters long) and they work well. A single long radial wire might be more convenient for rapid deployment in the field. Along with the Ground Tuning Unit (GTU) and a resonant vertical radiating element, a very acceptable SWR is obtained without the use of a tuner.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

TechTip #2 (revised): GTU hand capacitance

NB: This is a revised version of TechTips #2 with the addition of further details on how the issue of hand capacitance has been resolved.

The problem: Hand capacitance makes it difficult to accurately adjust the GTU.

The fix: Upon examination of my own GTU it was discovered that the layout had become too complex and the plastic enclosure provided no shield against capacitance between my hand and the RF circuitry. The solution is actually very simple; either re-assemble the GTU inside a metal enclosure, or provide some means of shielding the circuitry from hand capacitance. Since I didn’t have a suitable metal enclosure I elected to do the latter. The entire plastic enclosure was covered with aluminum duct tape. As an additional precaution, the duct tape was electrically connected to the ground binding post to ensure it remains at ground potential.

Did it work? Yes, I am pleased to report that this fix has entirely eliminated the problem. Here is a photo of the shielded GTU (KQ4TQ single inductance version):

The following is the pre-amble to the first version of TechTips #2 (now deleted to avoid confusion).

This is the second in an occasional series of short posts that zero in on details of a specific technical topic in relation to projects here on this blog, which some readers may find helpful.

A few weeks Ham Radio Outside the Box published a description of a “Mini Ground Tuning Unit (GTU)”. The schematic for that device is reproduced below. The design was then simplified with input from HROTB-Labs collaborator Tim KQ4TQ. Tim proposed a single inductance with a value of 3 microhenries (and generously donated a prototype he had built).

I built the revised GTU and performed many experiments in HROTB-Labs outdoor test facility (actually, my backyard). Various types of ground planes were tried, from G4AKC’s capacitance plate at the base of his pedestrian mobile radio trolley, to Faraday cloth (“magic carpet”), to ground radials.

My least favorite was the Faraday cloth. The one I used was about 1 square meter in area. I acknowledge the input of Paul VE3PVB who emphasized the need to maximize the area of the Faraday cloth to improve its efficiency. Two things about Faraday cloth are worth noting: first it has a shiny surface which can be distractingly reflective in bright sunshine. Second, it is often referred to as “magic carpet” – a very appropriate term since it has a tendency to fly in even a mild wind. Matt finish paint and a bag of rocks fixes both issues.

I settled on a set of 8 short radials (each 7 feet, or 2 meters long) and they work well. A single long radial wire might be more convenient for rapid deployment in the field. Along with the Ground Tuning Unit (GTU) and a resonant vertical radiating element, a very acceptable SWR is obtained without the use of a tuner.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

I realise that I could simply write to the developers of Supermium, but I wanted to ask those who are familiar with accessibility for help first. For a bit of background, I am switching from Windows 11 to 7. I will not debate this. The decision has been made and my primary machines are being upgraded with new drives and installations as I speak. I have an 11 machine if I absolutely need it, but it will not be used daily. Anyway, I primarily use Firefox, but sometimes, Supermium is better for certain things. This is a fork of Chrome that works with everything from XP through 11 and is updated often. The problem is that, unlike with Firefox, it doesn't save my passwords between portable versions. This is true of Chrome itself as well, even when logged into my account, and I have no idea why. Anyway, to avoid this, I would like to install it as a regular program on my machine. But the installer doesn't work with NVDA on 7. I haven't tried it on 10 or 11. It starts and then gets stuck and won't continue reading the options. I am fairly certain this is an open source program. Would it be possible for a standard installer to be written or for theirs to somehow be fixed? In contrast, the portable version uses their installer and works beautifully.

Portable
https://portableapps.com/apps/internet/supermium-portable

Standard 32-bit (they also have 64-bit)
https://github.com/win32ss/supermium/releases

#accessibility #blind #browsers #Internet #installer #portable #Supermium #technology #Windows7

I realise that I could simply write to the developers of Supermium, but I wanted to ask those who are familiar with accessibility for help first. For a bit of background, I am switching from Windows 11 to 7. I will not debate this. The decision has been made and my primary machines are being upgraded with new drives and installations as I speak. I have an 11 machine if I absolutely need it, but it will not be used daily. Anyway, I primarily use Firefox, but sometimes, Supermium is better for certain things. This is a fork of Chrome that works with everything from XP through 11 and is updated often. The problem is that, unlike with Firefox, it doesn't save my passwords between portable versions. This is true of Chrome itself as well, even when logged into my account, and I have no idea why. Anyway, to avoid this, I would like to install it as a regular program on my machine. But the installer doesn't work with NVDA on 7. I haven't tried it on 10 or 11. It starts and then gets stuck and won't continue reading the options. I am fairly certain this is an open source program. Would it be possible for a standard installer to be written or for theirs to somehow be fixed? In contrast, the portable version uses their installer and works beautifully.

Portable
https://portableapps.com/apps/internet/supermium-portable

Standard 32-bit (they also have 64-bit)
https://github.com/win32ss/supermium/releases

#accessibility #blind #browsers #Internet #installer #portable #Supermium #technology #Windows7

https://www.evshift.com/491932/mg-reveals-best-ev-hybrid-for-india-a-portable-generator-in-an-electric-car/ MG Reveals Best EV/Hybrid for India | A Portable Generator in an Electric Car #car #ELECTRIC #ElectricCars #ElectricVehicles #EV #EVHybrid #generator #Hybrids #india #PlugInHybrids #Portable #Reveals

A short 2-band ladder line antenna for portable ops

Introducing the 2B2L antenna

Wouldn’t it be nice to have a short, fairly efficient, rapidly deployable, low visual impact, vertical antenna that can be operated on both the 20 meter and 40 meter bands? The 2B2L (2 Band Linear Loaded) antenna comes very close to a perfect match for those specifications.

The 2B2L is the brainchild of Tim KQ4TQ who pitched the idea to me in an email recently. Seeing the potential in Tim’s idea, I hastily built a prototype and erected it in my backyard for testing. The 2B2L is based on the “Simple Ladder Line Antenna for Portable Ops” discussed a couple of weeks ago here on Ham Radio Outside the Box. But here is the genius in the 2 band version: by adding a loading coil and a tail section – also made from ladder line – to the top of the original single band (20m) version, we can add the 40m band. The whole antenna towers up to the dizzying height of just 15 feet!

But, just a moment; before the grey-haired, white-coated men with a physics diploma hanging on the wall pick up their quill pens to denounce the 2B2L, a confession is in order. Yes, admittedly, the 2B2L is not perfect; field portable antennas rarely are perfect. Those of us who like to operate out in the Big Blue Sky Shack must necessarily accept some compromises. Those of us who like to operate QRP accept even more compromises. So where’s the gotcha?

The loading coil for the 40m extension is the weak link. It serves two purposes: (1) it acts as an RF choke for the lower 20m band section; it’s high impedance effectively terminates the lower section of the antenna so that the top section does not affect operation on 20 meters; (2) it acts as a loading coil for the 40 meter top section which is considerably shortened as a result. But is it actually all bad? Yes, it has some loss due to the i^2R effect, but consider this: the whole antenna is radiating on 40 meters and the coil is near the top where the current is lower. If I am thinking with half a brain here please correct me in the comments. I did once think I was wrong, but I was mistaken!

Can an antenna that is only 15 feet tall really be efficient on 20m and 40m? The secret to how it can claim enough efficiency to actually make contacts out in the field lies in its use of linear loaded elements. Two sections of ladder line, each shorted at the top, provide the linear loading which shortens the required length by about 30%. Linear loading is considered one of the most efficient ways of shortening an antenna.

Also, the 2B2L is mounted quite close to the ground which inevitably diverts some RF to warming the earthworms. Mine is fed about 12 inches (~30 cm) above ground. It could also be raised higher and used with tuned, raised radials, but on 40 meters the radials would each be around 33 feet long. I chose to use short ground radials instead.

Where to buy a 2B2L?

Sorry folks, this is another real hobbyist’s project – you gotta build it yourself. You’re going to need some ladder line from whatever source you go to for ham radio supplies. Mine was a generous gift from my friend and CW buddy Mary VE3MVM. You will also need a coil. I had an air core coil lying in the drawer from a previous project. I built it using a a short section of PVC tubing about 2 inches (5 cm) in diameter. You will need an inductance meter, or a NanoVNA, to measure the inductance. As a purely rough guide, my coil has 35 turns of 20 awg stranded insulated wire. Here is the materials list:

• 11.5 feet (3.5 meters) of ladder line for the 20 meter radiating element
• 38 inches (0.97 meters) of ladder line for the 40 meter extension
• 35 microhenry coil

Setting up the 2B2L antenna

The 2B2L can be erected on a pole about 16 feet (or about 5 meters) tall. It is fed at the bottom via coax to a transceiver. The 2B2L requires radials. I tried a set of 8 radials, each 7 feet (2 meters) long. That worked but 4 radials, each 13 feet long provided a better return path on 40 meters.

In keeping with recent practise here on Ham Radio Outside the Box, the radials are tuned with a GTU (Ground Tuning Unit). The GTU has to be separately adjusted for each of the two bands. This ensures that the antenna system is working as efficiently as possible – without a tuner! An antenna analyzer connected via a short coax showed an SWR well below 1.5 could be obtained on both bands.

Does it QSO?

No, it just sits there grinning at the sky, but I have QSO’d using the 2B2L. My best contact so far has been a 2000 kilometer QSO with a station in Colorado on 20 meters by QRP CW. 40 meters is most active in the early morning and in the evening when I am inactive, but I am going to have to make the effort to go 40 meter QSO hunting real soon. Stay tuned.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

A short 2-band ladder line antenna for portable ops

Introducing the 2B2L antenna

Wouldn’t it be nice to have a short, fairly efficient, rapidly deployable, low visual impact, vertical antenna that can be operated on both the 20 meter and 40 meter bands? The 2B2L (2 Band Linear Loaded) antenna comes very close to a perfect match for those specifications.

The 2B2L is the brainchild of Tim KQ4TQ who pitched the idea to me in an email recently. Seeing the potential in Tim’s idea, I hastily built a prototype and erected it in my backyard for testing. The 2B2L is based on the “Simple Ladder Line Antenna for Portable Ops” discussed a couple of weeks ago here on Ham Radio Outside the Box. But here is the genius in the 2 band version: by adding a loading coil and a tail section – also made from ladder line – to the top of the original single band (20m) version, we can add the 40m band. The whole antenna towers up to the dizzying height of just 15 feet!

But, just a moment; before the grey-haired, white-coated men with a physics diploma hanging on the wall pick up their quill pens to denounce the 2B2L, a confession is in order. Yes, admittedly, the 2B2L is not perfect; field portable antennas rarely are perfect. Those of us who like to operate out in the Big Blue Sky Shack must necessarily accept some compromises. Those of us who like to operate QRP accept even more compromises. So where’s the gotcha?

The loading coil for the 40m extension is the weak link. It serves two purposes: (1) it acts as an RF choke for the lower 20m band section; it’s high impedance effectively terminates the lower section of the antenna so that the top section does not affect operation on 20 meters; (2) it acts as a loading coil for the 40 meter top section which is considerably shortened as a result. But is it actually all bad? Yes, it has some loss due to the i^2R effect, but consider this: the whole antenna is radiating on 40 meters and the coil is near the top where the current is lower. If I am thinking with half a brain here please correct me in the comments. I did once think I was wrong, but I was mistaken!

Can an antenna that is only 15 feet tall really be efficient on 20m and 40m? The secret to how it can claim enough efficiency to actually make contacts out in the field lies in its use of linear loaded elements. Two sections of ladder line, each shorted at the top, provide the linear loading which shortens the required length by about 30%. Linear loading is considered one of the most efficient ways of shortening an antenna.

Also, the 2B2L is mounted quite close to the ground which inevitably diverts some RF to warming the earthworms. Mine is fed about 12 inches (~30 cm) above ground. It could also be raised higher and used with tuned, raised radials, but on 40 meters the radials would each be around 33 feet long. I chose to use short ground radials instead.

Where to buy a 2B2L?

Sorry folks, this is another real hobbyist’s project – you gotta build it yourself. You’re going to need some ladder line from whatever source you go to for ham radio supplies. Mine was a generous gift from my friend and CW buddy Mary VE3MVM. You will also need a coil. I had an air core coil lying in the drawer from a previous project. I built it using a a short section of PVC tubing about 2 inches (5 cm) in diameter. You will need an inductance meter, or a NanoVNA, to measure the inductance. As a purely rough guide, my coil has 35 turns of 20 awg stranded insulated wire. Here is the materials list:

• 11.5 feet (3.5 meters) of ladder line for the 20 meter radiating element
• 38 inches (0.97 meters) of ladder line for the 40 meter extension
• 35 microhenry coil

Setting up the 2B2L antenna

The 2B2L can be erected on a pole about 16 feet (or about 5 meters) tall. It is fed at the bottom via coax to a transceiver. The 2B2L requires radials. I tried a set of 8 radials, each 7 feet (2 meters) long. That worked but 4 radials, each 13 feet long provided a better return path on 40 meters.

In keeping with recent practise here on Ham Radio Outside the Box, the radials are tuned with a GTU (Ground Tuning Unit). The GTU has to be separately adjusted for each of the two bands. This ensures that the antenna system is working as efficiently as possible – without a tuner! An antenna analyzer connected via a short coax showed an SWR well below 1.5 could be obtained on both bands.

Does it QSO?

No, it just sits there grinning at the sky, but I have QSO’d using the 2B2L. My best contact so far has been a 2000 kilometer QSO with a station in Colorado on 20 meters by QRP CW. 40 meters is most active in the early morning and in the evening when I am inactive, but I am going to have to make the effort to go 40 meter QSO hunting real soon. Stay tuned.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

RISCBoy is an open-source portable games console, designed from scratch

https://github.com/Wren6991/RISCBoy

Comments: https://news.ycombinator.com/item?id=48876245

#HackerNews #RISCBoy #open-source #gaming #console #portable #gaming #tech #innovation

RISCBoy is an open-source portable games console, designed from scratch

https://github.com/Wren6991/RISCBoy

Comments: https://news.ycombinator.com/item?id=48876245

#HackerNews #RISCBoy #open-source #gaming #console #portable #gaming #tech #innovation

The march of the cellphone brigade. Their's not to reason why, their's but to text or die...

https://www.flickr.com/photos/woolamaloo_gazette/55387569644/in/photostream/lightbox/

#Edinburgh #Edimbourg #photography #photographie #StreetPhotography #cellphone #phone #portable #LochrinQuay #Fountainbridge #PeopleWatching #BlackAndWhitePhotography

The march of the cellphone brigade. Their's not to reason why, their's but to text or die...

https://www.flickr.com/photos/woolamaloo_gazette/55387569644/in/photostream/lightbox/

#Edinburgh #Edimbourg #photography #photographie #StreetPhotography #cellphone #phone #portable #LochrinQuay #Fountainbridge #PeopleWatching #BlackAndWhitePhotography

Turning a $400 handheld console into a portable AI Dev Rig.

#handheldgaming #ASUSROGAlly #Ubuntu #googlecli #AIDevelopment #portable #technology #viralpost

Turning a $400 handheld console into a portable AI Dev Rig.

#handheldgaming #ASUSROGAlly #Ubuntu #googlecli #AIDevelopment #portable #technology #viralpost

TechTip#1 – a continuous loop of cordage

This is the first in an occasional series of short posts here on Ham Radio Outside the Box. The purpose of these TechTips is to share useful techniques I have learned over the years. I hope you will find them helpful.

TechTip#1 is an idea I picked up from a bushcraft video for creating a continuous loop of cordage. Of course, it is very easy to create a loop of cordage by simply tying the ends together with a knot. But that can be untidy and inconvenient, especially if the knot gets in the way of a neat join between two components of, for example, an antenna system.

How to use a continuous loop?

I use them a lot when erecting portable antennas. For example, if a cow hitch is formed at one end of the loop and a knot is tied at the end of a radial wire, the cow hitch can grip the wire end very securely – as long as tension is maintained in the loop. A second cow hitch can be formed at the other end of the loop to attach it to a tent stake. To release the wire simply pull out the tent stake, which relieves the tension and the wire is free.

Creating a continuous loop is surprisingly easy to do in just 3 simple steps.

STEP 1

Cut a length of thin cordage about 18 inches (46 cm) long. I use Atwood 1/16 inch (1.6 mm) Utility Rope, but any similar cordage, such as Bank Line, will do.

STEP 2

This is a very important step! Make sure both ends of the cordage are freshly cut, then melt the ends with a barbeque lighter, or similar. While the ends are still very hot press them gently together to form a bond. Be careful with this step because melted cordage can be quite painful if it gets on your hands. Being an amateur masochist I wait a couple of seconds then roll the join between two fingers to smooth the finished bond.

STEP 3

When the join has cooled – after just a few seconds – grab the loop either side of the join and pull like hell to test it. I was skeptical at first, but I can pull as hard as I like without breaking the bond. The Atwood cordage I use has a breaking strain of 110 lb (50 kg) and I suspect the join has the same strength.

If you have any similar amateur radio tips to share please send them to me via email, with photos if available and your tip will be featured here in a future Ham Radio Outside the Box TechTip.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

TechTip#1 – a continuous loop of cordage

This is the first in an occasional series of short posts here on Ham Radio Outside the Box. The purpose of these TechTips is to share useful techniques I have learned over the years. I hope you will find them helpful.

TechTip#1 is an idea I picked up from a bushcraft video for creating a continuous loop of cordage. Of course, it is very easy to create a loop of cordage by simply tying the ends together with a knot. But that can be untidy and inconvenient, especially if the knot gets in the way of a neat join between two components of, for example, an antenna system.

How to use a continuous loop?

I use them a lot when erecting portable antennas. For example, if a cow hitch is formed at one end of the loop and a knot is tied at the end of a radial wire, the cow hitch can grip the wire end very securely – as long as tension is maintained in the loop. A second cow hitch can be formed at the other end of the loop to attach it to a tent stake. To release the wire simply pull out the tent stake, which relieves the tension and the wire is free.

Creating a continuous loop is surprisingly easy to do in just 3 simple steps.

STEP 1

Cut a length of thin cordage about 18 inches (46 cm) long. I use Atwood 1/16 inch (1.6 mm) Utility Rope, but any similar cordage, such as Bank Line, will do.

STEP 2

This is a very important step! Make sure both ends of the cordage are freshly cut, then melt the ends with a barbeque lighter, or similar. While the ends are still very hot press them gently together to form a bond. Be careful with this step because melted cordage can be quite painful if it gets on your hands. Being an amateur masochist I wait a couple of seconds then roll the join between two fingers to smooth the finished bond.

STEP 3

When the join has cooled – after just a few seconds – grab the loop either side of the join and pull like hell to test it. I was skeptical at first, but I can pull as hard as I like without breaking the bond. The Atwood cordage I use has a breaking strain of 110 lb (50 kg) and I suspect the join has the same strength.

If you have any similar amateur radio tips to share please send them to me via email, with photos if available and your tip will be featured here in a future Ham Radio Outside the Box TechTip.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Save up to 38% in Positive Grid’s Spark Summer Sale https://rekkerd.org/positive-grid-spark-smart-guitar-amp-summer-sale/

#amplifier #disco #headphones #Portable #PositiveGrid #Sale

Save up to 38% in Positive Grid’s Spark Summer Sale https://rekkerd.org/positive-grid-spark-smart-guitar-amp-summer-sale/

#amplifier #disco #headphones #Portable #PositiveGrid #Sale

franceinfo: Le #téléphone #portable interdit au #lycée dès le "1er septembre" : c'est "absolument majeur pour nos #élèves", insiste Édouard #Geffray

#education #gouv #fr #france

J'attends de voir l'implémentation pratique le 1er #Septembre... ça va être un sacré why...

https://www.franceinfo.fr/societe/education/le-telephone-portable-interdit-au-lycee-des-le-1er-septembre-c-est-absolument-majeur-pour-nos-eleves-insiste-edouard-geffray_8065499.html

franceinfo: Le #téléphone #portable interdit au #lycée dès le "1er septembre" : c'est "absolument majeur pour nos #élèves", insiste Édouard #Geffray

#education #gouv #fr #france

J'attends de voir l'implémentation pratique le 1er #Septembre... ça va être un sacré why...

https://www.franceinfo.fr/societe/education/le-telephone-portable-interdit-au-lycee-des-le-1er-septembre-c-est-absolument-majeur-pour-nos-eleves-insiste-edouard-geffray_8065499.html

MicroUI – A tiny, portable, immediate-mode UI library written in ANSI C

https://github.com/rxi/microui

#HackerNews #MicroUI #ANSI #C #UI #library #portable #development #lightweight #immediate-mode

MicroUI – A tiny, portable, immediate-mode UI library written in ANSI C

https://github.com/rxi/microui

#HackerNews #MicroUI #ANSI #C #UI #library #portable #development #lightweight #immediate-mode

AudioThing releases Fields field recorder for iOS https://rekkerd.org/audiothing-releases-fields-field-recorder-for-ios/

#AudioThing #FieldRecording #iOS #Portable #recorder #Recording

AudioThing releases Fields field recorder for iOS https://rekkerd.org/audiothing-releases-fields-field-recorder-for-ios/

#AudioThing #FieldRecording #iOS #Portable #recorder #Recording

Hermes Portable: Because Your AI Assistant Should Fit in Your Pocket
I like tools that move with me, and I dislike reinstalling the same dependency circus on e
https://schulz.dk/2026/06/11/hermes-portable-because-your-ai-assistant-should-fit-in-your-pocket/?utm_campaign=blogpost&utm_medium=twitter&utm_source=twitter
#code #hermes #portable #project

Hermes Portable: Because Your AI Assistant Should Fit in Your Pocket
I like tools that move with me, and I dislike reinstalling the same dependency circus on e
https://schulz.dk/2026/06/11/hermes-portable-because-your-ai-assistant-should-fit-in-your-pocket/?utm_campaign=blogpost&utm_medium=twitter&utm_source=twitter
#code #hermes #portable #project

Как я написал портативный файлообменник

Каждый раз, когда нужно перекинуть файл, код или ссылку с ПК на телефон (или другу в той же Wi‑Fi сети), начинается классическая возня. Либо гоняешь через «Избранное» в мессенджерах (где режется качество и файлы вечно висят в облаке), либо поднимаешь локальные веб‑серверы через консоль. Мне это надоело, и я решил написать свою утилиту — FlashStash . Основная идея: софт должен запускаться в один клик, работать без интернета внутри локалки, иметь всеядный предпросмотр файлов прямо в браузере и не требовать от пользователя установки Питона или настройки окружения. После нескольких итераций проект дорос до версии 1.6, и я хочу поделиться тем, как устроена утилита изнутри и с какими техническими проблемами пришлось столкнуться.

https://habr.com/ru/articles/1045630/

#flashstash #файлообменник #локальная_сеть #python #flask #petпроект #portable #разработка #пиарюсь

#portable #karaoke #interactive #performance by #patrickjambon aka #turbojambon in #berlin #neukölln #2004
https://loops.video/v/g75t9Q1MtL

I got a vise and finally found appropriate base for it with a 2x8 but subpar fasteners - finally switched from drill driver to impact driver and impact worked good #portable temp base

I got a vise and finally found appropriate base for it with a 2x8 but subpar fasteners - finally switched from drill driver to impact driver and impact worked good #portable temp base

#portable : able to be easily carried

- French: portable

- German: mitnehmbar, portabel

- Italian: portatile

- Portuguese: portável

- Spanish: portátil

------------

Thank you so much for being a member of our community!

#portable : able to be easily carried

- French: portable

- German: mitnehmbar, portabel

- Italian: portatile

- Portuguese: portável

- Spanish: portátil

------------

Thank you so much for being a member of our community!

Writing Portable ARM64 Assembly

https://ariadne.space/2023/04/12/writing-portable-arm-assembly.html

#HackerNews #Writing #Portable #ARM64 #Assembly #ARM64 #Assembly #Programming #Portable #Code #Assembly #Language #Tech #Blog

Writing Portable ARM64 Assembly

https://ariadne.space/2023/04/12/writing-portable-arm-assembly.html

#HackerNews #Writing #Portable #ARM64 #Assembly #ARM64 #Assembly #Programming #Portable #Code #Assembly #Language #Tech #Blog

What to do when the bands suck?

Solar cycle #25 has reached its peak and is on the decline again. We may still have a few years of good propagation left but I am planning ahead. During the last solar minimum I adapted by … forgive me … increasing my transmit power. This time around I hope to keep working QRP, but increase my effective radiated power through bigger, more efficient antennas.

The peak of cycle 25 was actually quite a disappointment. The Sun became hyper-active spewing a few too many Coronal Mass Ejections, flares and high energy particles our way. Hopefully, now that the peak has passed, we might even get some less unpredictable propagation before we hit solar minimum.

As solar activity declines the higher bands seem to be open less often, so my personal focus is on 20m, 30m and 40m. Those bands are open throughout the solar cycle – except during solar storms of course. At least once per week I venture onto 80m for a CW rag chew with friends, but that is at the home QTH. When operating out in the woods 20m, 30m and 40m are my goto bands.

On the subject of “out in the woods” (my happy place), our local black bear population has awoken from its winter slumber and has been seen roaming in people places in my local town.

Bears are not usually a problem, they avoid human contact, but in the spring they are hungry and some of them associate people with food. Female bears with cubs can be very protective of their young which makes them potentially dangerous.

Antenna solutions for challenging conditions

One simple rule should be all that is necessary for getting a signal to propagate when the ionosphere is in combat with an angry Sun – or even when the Sun is dormant. Wire in the air = signal in the air. That is when it is probably a good idea to leave those very short, inductively loaded whips at home and start buying reels of wire and poles.

When I look back at what has worked in the past, the picture becomes very clear. Some of my small collection of QRP radios support only 20m, 30m and 40m. The 20m and 30m bands usually favor longer distance contacts, while 40m is better at shorter range. Out of these three bands I use 20m the most and, during the bottom of the solar cycle, 40m is my most used band. I don’t get on 30m very often; it is a WARC band and some operators dislike “contest-like” activity such as POTA on the WARC bands. No sense creating friction.

Best option for 20m?

This may be a bit of generalization, but a half-wave antenna launches more signal in the air than a quarter-wave. All half-wave antennas are not created equal. For example the very popular End-Fed Half-Wave requires a very carefully engineered matching device. Improperly engineered, one-size-fits-all, high ratio transformers often have very low efficiency.

A 5/8 wave vertical antenna may be even better in some circumstances – for example when the base of the antenna and all the radials are raised above ground. But 5/8 of a wavelength is a bit of a tall order – on 20m that’s 41 feet of antenna waving in the wind. Raise it above ground and you may have to attach a flashing red light at the top.

There is an even better solution. How about a 20m wire antenna that is low to the ground, is slightly directional and offers over 3dBi gain? Ham Radio Outside the Box explored this antenna three years ago; it is called the VP2E. Although VP2E sounds like a callsign (and it actually is a valid callsign) it is an abbreviation for Vertically Polarized 2-Element. It requires no tuner – and the VP2E is one full wavelength long.

I had great success with my VP2E before I stopped using it. It fell out of favor because of just one thing. Proponents of the VP2E claim that no baluns, ununs or feedline chokes are required. Perhaps, in theory, if the currents on either side of the feedpoint are balanced that could be true. In practise, even a small imbalance in the currents can lead to feedline radiation. To prevent this I added a current choke at the feedpoint.

Now this is where a problem arose. The feedpoint is not supported, so a choke hanging from the feedpoint pulls the wire down creating significant sag in the wire. The original choke that was used was made from 3 feet (~1m) of RG-316 coax looped three times through four snap-on ferrites; it weighed 126 grams.

The world’s worst 80m Common Mode Current Choke!

When I decided to resurrect the VP2E I wondered whether I could improve the choke to decrease its weight. I chose to get rid of the heavy ferrites and build an air-core coil choke. I found about 9 feet of RG-174 coax in my junque drawer. I also found an old pill container made of plastic so light it almost defies gravity. After winding the entire length of the RG-174 around the super light plastic former I hooked it up to my NanoVNA to measure its effectiveness.

I ran a scan from 3 to 30 MHz and noted the attenuation across the HF bands. On the 10m band the choke is exceptionally effective with a common mode attenuation exceeding 30dB. On the other end of the scale, the common mode attenuation on the 80m band was a lousy 8dB. Well, the VP2E is a monoband antenna built for 20m, so the choke’s performance on 80m is not a concern.

Performance on 20m is marginal, but acceptable, at -20dB. Since the current imbalance is likely to be small 20dB of common mode attenuation should be quite adequate. And, the new choke weighs in at 67 grams, nearly half the weight of the old choke.

It’s stealthy too

Apart from its gain, another benefit of the VP2E is that it only needs a short pole for support. 4.2 meters (13.8ft) is the recommended height. My crappie pole is about 0.2 meters short but modeling the antenna shows very little impact – you work with what you got!

Where to buy a VP2E

This a real hobbyist’s antenna; you can’t buy it, you gotta build it! A 100ft reel of thin wire – I use silicone coated 22ga wire – is all you need. Cut it to the lengths shown in the diagram above. Solder the wires to a piece of coax feedline and you are ready to get on the air. Choke? I think it helps but you can use the antenna without one.

A versatile short, strong, light support pole

The center of my VP2E is supported on a 13ft crappie pole which is very light for carrying into the field. It is very strong too. Well actually, I threw away the very top sections of two crappie poles and a made a strong, light single pole out of the lower sections. It mounts on a fiberglass driveway marker pushed into the ground.

The exact same pole also works for my 40m wire antenna. It’s a low dipole built for NVIS (Near Vertical Incidence Skywave). More details on that in a later post. Stay tuned.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Загрузка PocketHandyBox Linux с помощью TinyPXE Server, iPXE и WinNFSd

Подготовлены .ini файл с настройками TinyPXE Server, скрипт запуска WinNFSd, загрузочные файлы iPXE и скрипт autoexec.ipxe. В общем все необходимое для запуска PocketHandyBox Linux через PXE на почти любом ПК в локальной сети, используя в качестве сервера любой ПК/ноутбук с Windows. Благодаря поддержке в TinyPXE Server режима ProxyDHCP, при наличии в локальной сети основного DHCP сервера (без настроенной опции 67) / роутера - нет необходимости как либо вмешиваться в его работу. А также нет необходимости изменять IP адреса или файловые пути в каких либо конфигах. Все необходимое для запуска серверной части на Windows находится в одной папке. Не требует установки каких либо служб или правки реестра. То есть просто копированием переносится между разными Windows ПК и разными локальными сетями. Поддерживается загрузка через PXE как в UEFI так и в Legacy/CSM режимах. К сожалению Secure Boot не поддерживается и его требуется отключать. Начнем с краткой инструкции и продолжим более подробным разбором файлов конфигурации и дополнительных возможностей.

https://habr.com/ru/articles/1040350/

#pxe #ipxe #nfs #linux #windows #portable #debian #сетевая_загрузка #pockethandybox

Shocker! The #SteamDeck got a price hike!

- 512GB OLED = $789 ($200)
- 1TB OLED+AG = $949 ($300)

I cannot longer recommend the Steam Deck as entry level gaming.

If you want to play *something*, get a #MacMini or a #MacBookNeo... if you can find them.

How much the #SteamMachine will cost? $1,200? Will be DOA?

#Videogames #Gaming #Games #Steam #Valve #Handled #Handleds #Portable #PortableGaming #PortableGames #Hardware #PCHardware #PGGaming #Linux #Arch #SteamOS #PCGames #Computer #Computers

I've had a short look at #tilesontheair, a new #hamradio #portable program where you activate Maidenhead grid squares https://www.youtube.com/watch?v=_jBXYCBamn0