I've started dabbling in 2m SSB with my FT-857D and built a 5 element aluminum portable beam for it.? I have a noise problem though....??
I first experienced this issue when I took my radio on a work trip.? I setup the radio on 144.39 FM but I had full deflection on the s-meter.? I was not decoding any APRS until about an hour of it being on.? Suddenly, the noise dropped to S0 and I decoded everything.??
Just this week I tried to make a contact with a friend several miles away over the hill using SSB on 144.200 and this time I had S7 noise until about 15 minutes after power-on.? Then the noise dropped to S0-S1 and I was able to hear him.??
What could be causing high noise on 2m for a short while?? I haven't had the opportunity to do any more troubleshooting with antennas and dummy loads.? This happened both on battery power and an Astron linear power supply.
Common culprit would be a switch mode power supply close to you, or solar power controllers, mobile phone chargers. There are lots of things that can create noise. Where were you operating? -- Compton VK2HRX Sydney, Australia
Common culprit would be a switch mode power supply close to you, or solar power controllers, mobile phone chargers. There are lots of things that can create noise. Where were you operating? -- Compton VK2HRX Sydney, Australia
I have operated from in a city and from home out in the middle of nowhere when I have experienced this.? I don't remember it being a problem when portable away from everything.? It is possible this is RFI from something else; I can't rule that out yet.? At home I have a solar system and have fought RFI on the HF bands.? I have several commercial filters, mix 31 toroids, and grounding on all my solar RFI generators.? My power supplies in the shack are all linear now.? I haven't recreated this problem again yet but I'll continue monitoring and experimenting a bit.??
Well, there it is.? Right after I replied, I fired up the radio and there was S6-S7 noise at 144.200.? I cruised down the band and it completely disappeared.? So I removed the 857D from the equation completely to test.? I fired up my transverter and TS-890S.? I've attached a screenshot of the waterfall.? The T/R line is set at 144.200 and you can easily see the noise centered there as well as more down below.? I have two filters I'm waiting to install on my charge controller input and output.? I guess it is time!
Compton
