Oops, I replied to Luc and not the list. Meant to send follow-up to the list. LOL!
Begin forwarded message:
From: Nate Duehr nate@natetech.com Date: September 21, 2007 12:42:19 AM MDT To: Luc Leblanc lucleblanc6@videotron.ca Subject: Re: [amsat-bb] Re: Terrestrial QRM to FM satellites
On Sep 20, 2007, at 3:25 PM, Luc Leblanc wrote:
There are apparently several stations. I heard a part of a call "?A9??" on voice and at another time "/R" on CW on the 20:00Z pass of AO-27 over the US. Someone else was complaining of a strong unmodulated carrier for awhile. I guess I'll have to set the computer up to start recording. I doubt it's malicious. Hopefully it's just "I didn't know". But, as time passes, they will perceive ownership of the frequency, of course.
Bob
On the 2000Z AO-27 pass i was on this pass and i hear 2 folks discussing about a hamfest and they seems to be on a trunking system as we can copy clearly the "trunking tone" at the beginning of their transmission. AO-27 was over the eastern side of NA. If someone is aware of an amateur trunking like repeater this can give a clue even if the path of AO-27 was covering near all North America...
P.S. with 50W on a 14 elem cross yagi their signal capture mine!!! at a time!!!
My previous note notwithstanding, this description sounds like it might be a link transmitter for a voted receiver link on a large repeater system.
How high was the tone you heard Luc? 1950 Hz or 2175 Hz? Those are the two most common voter "pilot" tones for receiver links, one GE the other Motorola, typically.
Hams don't use much trunking but in certain areas of the country, voted receiver sites are heavily used, and they might be on VHF now that Auxiliary Stations are allowed in VHF, meaning that repeater links can also be allowed in VHF which wasn't allowable prior to this year -- or the thing might be throwing a wicked spur or something.
Generally, but not always... voted systems tend to be in high- population density areas, and the coasts and the eastern mid-west are the most common places to see them used. As you get into the Mountain West, the repeaters are high enough that voting receivers may or may not be useful for anything other than small "blackout" area fill-in coverage...
But that's not saying a whole lot -- it could literally be anywhere.
-- Nate Duehr, WY0X nate@natetech.com
-- Nate Duehr nate@natetech.com