#2mssb — Public Fediverse posts

Tropospheric ducting is a summer #hamradio phenomenon on the VHF & UHF bands, notably on #2mSSB. Range on the 144MHz band i typically limited to one's radio horizon. I'm at 600m ASL (2000ft) with a 12m tower, so my horizon is pretty far, 80km. With tropo, amazing things are possible.

I just worked Alan ZL1RQ, one of the NZ 2m powerhouses in Mangonui on the north Island. About 2200km. Summer has wound up, nice to get another ZL in the log before the tropo season closes.

Tropospheric ducting map looking promising toward ZL from VK2 in the next day or so. #2mSSB #hamradio contacts over 2200km is always exciting.

Tropo maps courtesy of Pascal F5LEN via https://tropo.f5len.org/australia/

Aircraft bounce is a common mode of propagation between Sydney and Canberra/South Coast on #2mSSB #hamradio. The spots tell the story. a/c queuing to land at SYD are convenient passive reflectors in the weekday mornings. When aircraft (blue lines) cross the radio paths (red) it's like having a very low orbit satellite repeater between the locations. Rod VK2TWR was a solid 5x7 off the jets, very strong for 328km.

very nice #hamradio signals on #2mSSB this morning, Lots of aircraft between me & Canberra to bounce radio signals. A few big freighters off to China crossing the path to Carl VK2TP in Wellington, too

Tropospheric ducting map looks very promising for a #2mSSB #hamradio contact into NZ, but it's pretty late there now (1:30AM) and there's a heap of storms to my S which are making a lot of static noise, will call a few times but I don't like my chances

Some delicious grape lemon-lime blobby goodness on the tropospheric ducting forecast map today, good for some 200km-ish #hamradio contacts on #2mSSB. I'm on a 600m (2000ft) above sea level mountain ridge and have a 12m (40ft) tower, so my radio horizon is about 80km (about 7-10km if I was in the flatlands), but the rest of the extraordinary distance is accounted for by atmospherics.

Sure enough, just got Nick ZL1IU on NZ north island in the log. Deep QSB, sigs up & down but 5x3 when sigs are up #hamradio #2mSSB

yummy tropospheric ducting blobs between Aus & NZ on the tropo map this morning. Just wked Nick ZL1IU in Northland on the N island. 2144km is a BIG hop for #2mSSB. Nick using 4 stacked 12 element yagis and 1000W. I heard him at 5x7. My 9 el yagi on a 12m tower on a 600m/2000ft ridge in the Blue Mtns & Mirage 160W amp registered 5x5 on his end.

Heaps of other #hamradio stations making good use of the #2mSSB atmospheric shenanigans this morning.

A bit of springtime #2mSSB tropospheric ducting on the east end of VK, always a bit of #hamradio fun when the atmosphere makes a line-of-sight band do unusual things. 144MHz normally only goes to the radio horizon, about 80km for me at my 600m/2000ft elevation in the Blue Mountains. Worked Rod VK2TWR & Ian VK1BG at about 330km. 9el 14.1 dBi yagi on 12m tower with 160W, about 3400W EIRP to make the hop..

The last 3 days are going to be known to #hamradio ops in VK & ZL as 'The Great Tropo Opening of 2023.' All that blobby goodness in the Tasman makes stations on both sides sound like they are down the block from each other, but it is 2200km on a band which normally goes no further than the horizon, which is 80km for me. I have wkd Nick ZL1IU every day for the last 3 days and also logged Al ZL1RQ today. Heaps of VK stations making #2mSSB contacts across the ditch, also some on 70cm.

Here's Nick ZL1IU working VK4EKA in Queensland. Nick has pointed his beam a bit north to favour the VK4 station so he's not quite as loud as he was when talking to me. We don't hear the VK4 because my beam is pointed at NZ. #2mSSB #hamradio

Couldn't catch Nick ZL1IU saying his callsign in this clip but he's the first voice. Huge signal, just as loud as a local. #2mSSB #hamradio

I made the contact with a 9 el yagi at 12m/39ft AGL, QTH is 600m/2000ft ASL. Even with that elevation, my radio horizon is just 80km, so this is a lovely surprise. Wkd Nick once before in Dec 2022. Power 160W from Mirage B2518G linear amp, rig is IC-7000 #2mSSB #hamradio

Fantastic tropospheric ducting #2mSSB #hamradio contact just now with Nick ZL1IU on NZ north island, 2144km. Lots of eastern VK wkng Nick. VK2MAX also wkd N Is on 432MHz. Wild stuff! Remember, 144MHz is normally line-of-sight until the exotic atmospheric phenomenae come out to play.

This is the elevation profile of the path between me and Greg VK1AI- we are both about 600m above sea level. You can see topographic prominences up to 1000m between us' The aircraft we were bouncing sigs from were at about 33,000ft or 13,000m. I have a 9 element Yagi directional antenna on a tower at about 12m above ground level. I used 160 watts from the black Mirage linear amplifier to make the #2mSSB #hamradio contacts.

I was just able to use the aircraft scatter effect to make 3 short #2mSSB #hamradio contacts into Canberra, about 220km away.

You can hear the effect in this clip. The varying signal strength and warbling in the tone from the beacon station are caused by signal reflections from several aircraft as they cross the radio signal path. My normal maximum range on #2mSSB is about 80km. This #hamradio beacon is about 330km away in Nimmitabel NSW.

In winter, we don't usually get the temperatures necessary to produce inversions which create tropospheric ducting conditions that can carry #2mSSB #hamradio signals further than my 80km radio horizon. There's almost always some jets queueing to land at SYD which cross the radio path between me and Canberra. which produce very brief band openings over this 220km path. Worked Rob VK1KW, can hear Greg VK1AI, will ring his chimes in a minute or two.

SYD bound aircraft on holding patterns giving good opportunities for aircraft bounce #hamradio #2mSSB. Just worked Greg VK1AI in Canberra, sigs up to 5x7 during brief QSO. Need that aircraft bounce to get over the mountains in the southern highlands.

A line of aircraft heading for Sydney giving opportunities for #2mSSB #hamradio signal bounce this morning. Some minor tropospheric propagation happening but not strong. Wkd Greg VK1AI in Canberra. Always amazing to me that this works considering there are 1000m mountains between Canberra & me with Greg & I both at about 600m.

Good #hamradio #2mSSB DX hunting this morning, helped by bouncing signals from aircraft which were in holding patterns near Goulburn & Moruya. Worked Rod VK2TWR & heard his 144.414MHz beacon 328km down teh south coas. Greg VK2AI was very loud at 5x7 with aircraft bounce assistance. Steve VK2ZT in Medowie, north of Newcastle, is coastal with few obstacles between he and I- my sheer 600m elevation is enough to make the trip, no tropo or aircraft bounce needed. he's nearly line-of-sight, but at 170km, curvature of the earth is a problem as he's below my 80km radio horizon. Steve has a 400watt amp which makes him easy to hear. I run a Mirage 160W amp into a 9 element yagi on a 12m tower (that I am not usually standing on).

Bit of purple blobby goodness on the tropo forecast but not over my area. Still getting some #hamradio #2mSSB benefit from it as there's no jets on FR24 to bounce sigs off of. 3 quick QSOs into Canberra, Al VK1RX, Greg VK1AI & Ian VK1BG . Tall signal obstacles in the Southern Highlands between me & VK1, certainly some sort of propgation enhancement afoot

Lots of jets queued up to land at SYD this morning giving a nice AE bounce for the 414 beacon, very strong 579 to 599 CW sigs. 328km is a very good hop on 144MHz considering my radio horizon is only 80km #hamradio #2mSSB

Some purple & green tropospheric ducting goodness on the map. Worked Rod VK2TWR at 328km down the south coast, easy 5x7. Condx like this shouldn't really exist until summer as tropo relies on a temperature inversion, bad omen for an upcoming hot summer #hamradio #2mSSB

hmm. tropospheric ducting at this time of year? A temperature inversion is required- cool air at ground level, warm air about 1000m or so above it. This is why tropo ducting is typically a summer atmospheric condition. Problem is it is the middle of the middle month of winter in the Blue Mountains. It's almost like the climate is changing or something. #hamradio #2mSSB

Easy contact with one of the Canberra crew, Greg VK1AI, 220km

bear in mind that signals at 144MHz travel line-of-sight, my radio horizon is 80km and there's 1100m mountains between us

tropo is a beautiful thing, making the impossible possible on the regular #2mSSB #hamradio

Heard Rob VK1KW a minute ago, will put out a call

woo! Lots of purple and green tropospheric ducting blobby goodness on the forecast map this morning. Need to get a coffee, fire up the 160W Mirage amp & hunt a bit of #2mSSB #hamradio DX. Unseasonal- this level of propagation is more typical of summer weather.

A bit of off-season tropospheric ducting on #2mSSB #hamradio. Dave VK2DVM in Blackheath is working Peter VK5PJ in Tanunda, South Australia. That's 1059km!

I can't hear Peter because of the sharply rising terrain to my west as you see in the elevation profile, but Dave is on top of those peaks. No trouble for him having an easy armchair QSO with Peter. I can also hear Rob VK1KW in Canberra talking to Peter.

I do have a good perch at 600m ASL so I can work distant stations in pretty much all directions EXCEPT due west.

Very few aircraft on the radio path toward VK1 but the 144.414 beacon down south in Nimmitabel is audible. Might be some off-season tropo ducting considering we have moggy wx conds in the Mtns this morning #hamradio #2mSSB