#tropo — Public Fediverse posts

RE: https://mastodon.radio/@vu3dxr/116477377130505089

Even if you don't have your ham licence, you can still use #Tropo to listen to VHF/FM #radio stations many hundreds of km away from your location (this weekend I heard many from Netherlands, Germany and even a community station from Northern England (330 km away from me!)

Quite a bit of #tropo on #VHF - this is received in my car parked outside my office in Mid Suffolk (so 30 km away from the coast), and still the radiosignal from #Televisietoren #Goes #Zeeland gets through!

#FM #DX #Radio #Broadcasting #NPO3

https://tube.tchncs.de/w/55f1qsiFU3k1Yz7B2cvwCs

Quite a bit of #tropo on #VHF - this is received in my car parked outside my office in Mid Suffolk (so 30 km away from the coast), and still the radiosignal from #Televisietoren #Goes #Zeeland gets through!

#FM #DX #Radio #Broadcasting #NPO3

https://tube.tchncs.de/w/55f1qsiFU3k1Yz7B2cvwCs

Quite a bit of #tropo on #VHF - this is received in my car parked outside my office in Mid Suffolk (so 30 km away from the coast), and still the radiosignal from #Televisietoren #Goes #Zeeland gets through!

#FM #DX #Radio #Broadcasting #NPO3

https://tube.tchncs.de/w/55f1qsiFU3k1Yz7B2cvwCs

Quite a bit of #tropo on #VHF - this is received in my car parked outside my office in Mid Suffolk (so 30 km away from the coast), and still the radiosignal from #Televisietoren #Goes #Zeeland gets through!

#FM #DX #Radio #Broadcasting #NPO3

https://tube.tchncs.de/w/55f1qsiFU3k1Yz7B2cvwCs

Quite a bit of #tropo on #VHF - this is received in my car parked outside my office in Mid Suffolk (so 30 km away from the coast), and still the radiosignal from #Televisietoren #Goes #Zeeland gets through!

#FM #DX #Radio #Broadcasting #NPO3

https://tube.tchncs.de/w/55f1qsiFU3k1Yz7B2cvwCs

Well that was an absolute blast. Played radio with @DafyddJack from some high ground in north east Wales this afternoon. Worked Germany (multiple times), The Netherlands and France on #2m #SSB, 30-50w TX power and a 3 element SOTAbeam.
Before today neither of us had worked mainland Europe on 2m. #AmateurRadio #HamRadio #vhf #vhfdx #dx #tropo

Last night (20250526 0951Z) on 2m I could reach the Sicilian repeater IR9D at Monte Erice (145.775 MHz, tone 94.8) locator JM68ha) 1150 km away from me (IM98ri). I was using 50 W. I had a very nice QSO with Adriano IT9HMH who was on mobile near Trapani. I love Mediterranean tropospheric ducting.

#tropo #2m

Radio Propagation

As an area of high pressure is moving back into northern Europe and the British Isles this weekend, an associated area of "weak" to "good" tropospheric radio propagation tries to push in too. Enhanced radio conditions may reduce by the end of the weekend, although they may improve again later in the week.

Enhanced tropospheric radio conditions extend the normal range of VHF and higher signals beyond their normal range.

#radiopropagation
#tropo
#amateurradio

Radio Propagation

Lots of activity on the 2m band is being reported across southern and eastern Scandinavia tonight which is reported as Tropo propagation. I'm not seeing any matching tropo reports on fmlist.org, nor a forecast for topo propagation on F5LEN tonight, so this might be contest activity. Could someone in the area confirm?

#radiopropagation
#amateurradio
#tropo

à cause du #brouillard, j'ai pu écouter France Info sur #VHF pendant 2 jours (QTH Mid Suffolk, Angleterre)

because of #fog, I could hear France Info on 105,2 MHz since last 2 days (QTH Mid Suffolk, England)

#radio #tropo #climate #ClimateDiary

Yesterday I drove to the rural area to visit relatives from Christmas (a good 30km inland from the North Sea coast).

Both on the outward and return journey I heard #FranceInfo loud and clear on 105,2 MHz VHF/FM, including a #weather report from #MéteoFrance where the reporter mentioned unusual levels of humidity for the season ( which was likely the cause of all this #Tropo and linked to #ClimateChange )

Radio Propagation

"Good" "Strong" tropospheric radio propagation on VHF bands across the southern British Isles and Northen Europe.

This is my haul over the past two hours from a quick scan of the FM band (map and log courtesy fmlist.org).

#fmdx
#tropo
#amateurradio
#radiopropagation

It was 114F in Durango, Mexico and a sandstorm, per XE2CGA, based on radio traffic heard in off the coast of Ventura, California today heard 1150 miles away on VHF earlier today (Repeater on 146.940... in Villa Del Campo, Mexico... about 220 miles away -- I believe we were hearing ducting from a repeater in Baja Mexico!!). It appears there is a huge, linked repeater network up and down Baja Mexico. #hamradio #tropo

Radio Propagation

Sporadic-E over northern France is causing a high MUF (Maximum Useable Frequency) over northern Europe this lunchtime. Propagation into FM Band 2 is taking place (1st map, brown lines).

A large high pressure area over Europe is also providing settled conditions with elevated tropospheric propagation conditions across the continent (2nd map).

#radiopropagation
#sporadic
#tropo

Radio Propagation

With all the solar flares, the ionosphere is in a poor state and the HF band is pretty dire at the moment. The higher frequencies (like VHF) may provide more entertainment!

Northern Europe is currently enjoying a large area of high pressure, and tropo propagation is good across the region.

Here we see Ship AIS pings on 162 MHz in the English Channel received at my station in Plymouth.

See the live map here:
https://www.shipxplorer.com/stations/SXAISD0000588

I'm happy to report that my station is ranked as #1 reporter in the UK on the ShipXplorer website!

#amateurradio
#radiopropagation
#tropo

Radio propagation: Good to strong tropospheric radio conditions are continuing over north-east Europe. For explanations of what causes this please read my earlier posts.

See live propagation maps on my website: www.tvcomm.co.uk/g7izu

#radiopropagation
#amateurradio
#tropo

Radio propagation: Good to strong tropospheric conditions are prevailing across the north of Europe thanks to settled weather. Tropo can extend the normal range of VHF/UHF signals by hundreds of km beyond their normal range due to tropospheric ducting between layers of the lower atmosphere. Settled weather produces the best conditions for this.

https://tvcomm.co.uk/g7izu

#RadioPropagation
#FMRadio
#tropo
#AmateurRadio

À cause de la propagation troposphérique j'ai pu écouter France Info sur 105,2 MHz FM dans ma voiture en Angleterre avec RDS

Because of a #tropo lift , I could listen to France Info on 105,2 Mhz FM from my car in England, with RDS..

#radio #dx #tropo #radiomonitoring

calling now on 217°, that should find VK1RX & VK1KW in the northern end of the ACT #hamradio #tropo #2mSSB

There's some #2mSSB #tropo #hamradio going this morning. When there's contacts being made across the Bass Strait, where there are precious few aircraft movemets, you can be pretty sure it's not aircraft scatter propagation.

Big #Tropo lift on #VHF, #FM at the moment - just heard Park Radio on 107,6 MHz from Harleston in South Norfolk here in Mid Suffolk (a 33km distance, unusual for a community radio station to go that far!) #radio #CommunityRadio

#radio enthusiasts: there is a #tropo lift across Northern Europe (and SE/East England) at the moment, I am comfortably listening to NPO Radio 1 NL (104,4 MHz) from the Sangean PL-880 portable in the top stairwell of my house..

there is #tropo tonight in #Northern #Europe : the pirate stream I was listening to from #Twente closed down (its midnight, the DJ sounded quite tired) and I could hear a German station in the background (they wouldn't normally deliberately cut across a licensed broadcaster, BNetzA don't like it!), and when I turned on the #FM #radio in my stairwell I can hear NPO Radio 1 on 104,4 loud and clear (but I didn't really want to listen to their boring political discourse 😆 )

#radiomonitoring

#radio enthusiasts: there is a big #tropo lift in #UK and #Northern #Europe atm, I am monitoring French and Dutch stations loud and clear on Band II (FM) from the landing of my house with just the internal antenna of my Sangean RX (for some reason the best reception is on the stairwell next to the airing cupboard, I think an old piece of copper pipe in there (not connected to anything at either end) acts as a reflector 😉

#radiomonitoring

http://www.dxinfocentre.com/tropo_nwe.html

if any East Anglian folk (and maybe even those in outer London) are still awake and have an FM #radio to hand, all sorts of FR/BE/NL stations are coming in strong to UK via #tropo

you don't need an "anorak grade" specialist receiver to listen to this, any portable radio will work, even your mobile phone if it has FM radio works (remember to plug in headphones to work as antenna), if possible go to the highest point in your house away from switched on computers and other interference sources..

just heard / ik heb pas gehoord Joe FM, uit België 104,1 MHz (zendmast bij Egem(?)) en een stukje van Radio 1 NPO NL op 104,4 MHz (zendmast Goes)

#radio #fm #dx #tropo

#radio enthusiasts : currently high levels of #tropo over Eastern England, I was able to receive France Inter 105,2 MHz *downstairs* and even on my 1980s transistor radios (as well as the more modern Sangean with better selectivity).

At one point even getting a clear signal with the radio placed on the couch barely 1m from this Acer laptop (which is a bad QRM generator..)

http://www.dxinfocentre.com/tropo_nwe.html

Protecting Against Credit Card Scams

https://shkspr.mobi/blog/2012/07/protecting-against-credit-card-scams/

I recently read about an innovative telephone call scam.

A scammer rings the mark and asks for her credit card details. If the mark refuses, the scammer tells her to hang up the phone, then dial 999 and ask for "Sergeant Scammer of the Fraud Squad".

The mark does so, and is connected to what they assume is the emergency services. However, because the scammer hasn't hung up at their end, the call is still active. So the mark isn't speaking to 999, but to the scammer.

Pretty devious. Luckily, it can't work on mobile. But it got me thinking - how could you get someone to give you credit card details over the phone? I'm inspired by both Bruce Schneier's "Movie Plot Threat" competitions and Kevin Mitnick's work on Social Engineering.

Trying to think like "the enemy" is a crucial part of understanding how nefarious people can exploit a situation. I think it should be considered the seventh "thinking hat".

The Goal

I want the victim to willingly give me her credit card details. I do not want her to be suspicious or report my activity to the police.

The Strategy

• The victim receives a text on her phone.

• "Your Barclay's credit card (starting 4304) was recently used to buy £2,103.54 worth of goods in China. If you wish to dispute this transaction, please call 0113 496 0123."

• The victim checks her BarclayCard - it does start 4304. Damn! She rings the number.
• "Welcome to the BarclayCard fraud line," says the voice at the other end.
• "To protect your security, please type in your sixteen digit card number," says the automated voice. So that's what the victim does.
• ... after typing in several more details, the victim finally gets through to the scammer.
• At this point, the scammer can attempt to get more information - such as home address - or simply assure the victim that the fraud has been reported.
• "Unfortunately," the fraudster says, "the £2,103.54 will show up on your July statement. But you will see the refund on the August statement."

How It Works

There are a number of factors which go into making this a potentially successful scam.

1. People are quite used to receiving texts from their card issuer.
2. It's quite common to be asked to confirm a suspicious transaction.
3. Credit cards number have a predictable start sequence. That's why credit card receipts often show you only the last few digits. This tricks the victim into thinking that the scammer knowa two crucial pieces of information; the credit card issuer and the credit card number.
4. We're trained not to give details to strangers who ring us up. By contrast, we're expected to give details to people when we ring them!
5. You can't argue or otherwise interrogate an IVR. You either have to give that disembodied voice your details or hang up.
6. Again, we're quite used to typing in our credit card details and then pressing the hash key!
7. If we do get through to a real person, the standard Social Engineering tricks all apply. Only, in this case, not only is the victim worried about the potential fraud, she has also primed herself into thinking she's speaking with her credit card provider.
8. At this point, the scammer knows that they can use the card for a fraudulent purchase and the victim won't report it! It will only be after two statements have been received that the victim will notice that she hasn't been refunded.

Problems

Now, this fraud isn't without issue. The most notable being that you do not know who has a credit card issued by a specific provider. The scammer would either need some third party intelligence that their victims all use HSBC, or they could just go on a phishing expedition. Spam a few thousand numbers and there will bound to be a few which have the card which is being targeted.

How To Do It

Using services like Twilio and Tropo, it's quite easy to create a telephone menu. It can play back a recorded voice, save all the user's keypresses, then pass the call on to the scammer.

They can even handle the automated sending of the text messages, playing back different messages depending on the caller - "Welcome to HSBC", "Welcome to American Express", etc.

Defending Against This Scam

There are three main strategies for defending against this scam - and they all boil down to trust

Don't Trust An Unknown Phone Number

Save your credit card provider's phone number in your address book. That is the only number you should ring. If someone rings you - tell them that you will take their name and call them back on the official number. If you receive a text - call the official number to check it is legitimate.

Don't Trust Partial Information

The first few numbers of your credit card are fairly generic. Trusting someone who guesses your Visa Electron starts with "4197" is like trusting a psychic who says "You were a bit of a handful growing up, especially in your teens." It's such general information as to be worthless.

Don't Trust The Other Person

I sometimes act deviously. When asked to give my address, I'll give an incorrect house number or post code. If the person at the other end doesn't pick up on the mistake, I assume I'm talking to a scammer. Similarly, you don't have to trust interactive menus. You can input incorrect information, and see if it is accepted without complaint - a sure sign of a scam. Or see if it gets you through to a human.

Is This Scam Possible?

One hurdle is targeting enough people who have the "correct" credit card. The scam would work without the credit card info, but may be less effective.

The cost of sending out the texts is also a constraint. Although text bundles are relatively cheap now.

Shutting down the numbers - or tracing them - is perhaps the biggest issue. Buying a disposable pre-pay SIM is virtually anonymous. A landline number is probably fairly easy to trace - assuming the police have the time and staffing levels to investigate such a scam.

And that may be the deciding issue. If someone reports a suspicious text to the police or their credit card provider, how quickly can the number be shut down? If the scammer is sending out hundreds of fraudulent SMS an hour, it would only take a few responses to make the scheme worthwhile.

Disclaimer

Naturally, you should not attempt this. The penalties for credit card fraud a very serious. This is intended as a thought experiment.

If you want people to willingly give up their credit card information - take a look at the morons on Twitter posting photos of their cards!

#creditCard #fraud #scam #sms #tropo #twilio #voice