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Vintage Amateur and Military Radio Amateur/military receivers and transmitters, morse, and any other related vintage comms equipment. |
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1st Oct 2021, 8:21 am | #21 |
Hexode
Join Date: Mar 2006
Location: Helston, Cornwall, UK.
Posts: 303
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Re: AM on 80m - Much Happening?
For the last 6 months I’ve been suffering with intense QRN right across 80 60 and 40M making QSO’s very difficult, recently Western Power have been doing some work and bingo, noise disappeared so I’ve been on AM a bit on 80 and 60M, really good signals recently in the mornings on 3615 and as we go into winter it will be worth calling anytime during the day.
Modern SDR based rigs produce very good AM, I have a IC7610 and always get good reports although it’s not as good fun as a vintage rig.. (Anyone got a KW Vanguard or DX100 for sale?). If you run AM on 60M watch your bandwidth. If you want a sked PM me. Tim M0AFJ Helston Cornwall |
1st Oct 2021, 10:04 am | #22 |
Octode
Join Date: May 2016
Location: Oxfordshire/Bucks borders, UK.
Posts: 1,604
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Re: AM on 80m - Much Happening?
It's still going on, or something is on the same frequency and mode.
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Avometer, vintage Fluke and Marconi collector. Also interested in vintage Yaesu and KW. |
1st Oct 2021, 6:25 pm | #23 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 14,005
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Re: AM on 80m - Much Happening?
There's also quite a bit of late-afternoon AM operation on 3615: so far today as part of my "Five-a-Day" HF QSO-target I've worked a station near Birmingham, one north of Swansea and one in Ireland.
All using around 10 Watts from my 1970s-vintage military PRC320 into a 100-foot-longwire. Its rather-aggressive VOGAD speech-processing (courtesy of Plessey's IC development team in Swindon) is rather good at getting through the noise. You need to be in the right place at the right time - as dusk falls and the 'gray line' moves in from the East you start to get more and more Continental SSB stations coming up out of the noise. This is where a 'selective sideband' receiver can help: put the incoming AM through a SSB filter to lop-off one sideband and some of the carrier; then reintroduce the carrier at high-level from a local oscillator and demodulate the result as SSB. Though purists would say you need the local carriier to be phase-locked to the vestiges of the transmitted carrier, in practice a solid local carrier will swamp the transmitted carrier and you then 'tune for the lowest growl'. |
1st Oct 2021, 6:34 pm | #24 |
Nonode
Join Date: Mar 2005
Location: Nuneaton, Warwickshire, UK.
Posts: 2,039
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Re: AM on 80m - Much Happening?
The main AM activity will be tomorrow morning on the VMARS net. It starts at 0830 but there is always a pre-net gathering from anytime after 0600, depending on conditions.
Cheers Aub G4KQL and VMARS member
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Life's a long song, but the tune ends too soon for us all. |
1st Oct 2021, 7:57 pm | #25 |
Nonode
Join Date: Mar 2005
Location: Nuneaton, Warwickshire, UK.
Posts: 2,039
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Re: AM on 80m - Much Happening?
Should like to add that any licenced person is welcome to join the net, you don't have to be a VMARS member, as long as you use AM from whatever rig you like.
Aub
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Life's a long song, but the tune ends too soon for us all. |
2nd Oct 2021, 3:39 pm | #26 |
Octode
Join Date: May 2016
Location: Oxfordshire/Bucks borders, UK.
Posts: 1,604
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Re: AM on 80m - Much Happening?
Listened again this morning, yesterday appeared to have stronger stations. I will join in one of these days, but for now I may have to drop my vertical as it's getting an absolute battering from the high winds, I need some additional guys. I'll probably pull the long wire back up and see how that goes.
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Avometer, vintage Fluke and Marconi collector. Also interested in vintage Yaesu and KW. |
2nd Oct 2021, 3:56 pm | #27 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,289
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Re: AM on 80m - Much Happening?
Plent of activity there this morning, but most stations are buried in S9+ noise at my location.
Guess I need a magnetic loop aerial
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Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
2nd Oct 2021, 4:36 pm | #28 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 14,005
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Re: AM on 80m - Much Happening?
A longwire is what I'm using - it's not that high up - indeed height can be unhelpful. For good intra-UK working you are often better off with a wire only 10 or 20 feet up, so you get plenty of ground-reflection - have a look at "NVIS" antennas [sometimes nicknamed cloudwarmers].
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2nd Oct 2021, 4:44 pm | #29 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,289
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Re: AM on 80m - Much Happening?
I'm using a 150Ft long wire at 20ft height running North-South.
Could put up a half wave dipole, but I expect the noise level would be similar.
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Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
2nd Oct 2021, 5:18 pm | #30 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 14,005
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Re: AM on 80m - Much Happening?
Your longwire sounds like it should be good on Tx.
For Rx you could even try a ferret rod; in the past I've used ferrite rods on 160 and 80M and their directivity is useful for nulling-out noise if the source is in a determinable direction. Alternatively you could look at having a separate 'noise' antenna arranged to pix up as much noise as possible, then phase it against the main receive antenna to null out the noise - a quick search of "Jones noise balancer" will reveal how the US air-force did this on WWII bombers to null-out the interference from the spark-plugs of multiple Wright Cyclone engines! |
2nd Oct 2021, 9:06 pm | #31 |
Pentode
Join Date: Feb 2020
Location: Camborne, Cornwall, UK.
Posts: 128
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Re: AM on 80m - Much Happening?
There were 19 stations logged for the first AM-ARS net on 19th Sept. I first called in early in the net and was acknowledged, using an Elizabethan XMTR, designed by G5RV in 1955. I had a series of lighting problems in the shack so rigged up a "portable" XMTR in the house and managed a couple of contacts just before the net closed down.
The next one is 19th October at 19.30 local time, 3.625MHz: a much more civilised time of day than early morning! 73 Rod M0LXY |
3rd Oct 2021, 1:12 pm | #32 |
Nonode
Join Date: Feb 2005
Location: Worcestershire, UK.
Posts: 2,533
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Re: AM on 80m - Much Happening?
There used to be a NBTV net on 80 metres. Just the job if you had a MUTR Televisor to view the 32-line pictures.
Steve
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