I ran the experiments for 2 passes. 28Apr 1608 UTC and 29Apr 0245 UTC. The first pass was just a few minutes before it switched to the video mode. The second pass was high elevation and 11 minutes.
It was mentioned that the interference might be from a 145.110 MHz repeater due to the 3rd harmonic. Also mentioned were towns heard in the conversation and that there was a courtesy beep. A repeater in our area that fits all those items in the N1CON repeater in Concord MA.
For both passes I heard the bird fine and there were ongoing QSOs. During the passes I transmitted periodically on the repeater announcing my call and 'testing' to cause some audio on the repeater. Also had another station transmitting on the repeater. Throughout the test I did not hear any interference on the downlink. So also, I did not listen to the uplink frequency since there did not seem to be any interference at that time. I am using different radios for TX and RX, and antennas that are far apart for the tests.
I'll check from time to time listening to the downlink. If I hear the interference, I can both check the uplink frequency and also listen to the local repeaters. There are many in this area.
73, Eric KV1J FN42 (West of Boston MA)
-----Original Message----- From: Eric Williams [mailto:[email protected]] Sent: Tuesday, April 28, 2020 11:14 AM To: '[email protected]' [email protected] Subject: RE: Repeater interference on AO-92
Yes, I am also listening to the uplink freq. Next pass is in about 1 hour. 73 Eric KV1J
(I use digest mode for this list so pardon the not including the string of messages)
-----Original Message----- From: Eric Williams [mailto:[email protected]] Sent: Tuesday, April 28, 2020 10:51 AM To: '[email protected]' [email protected] Subject: RE: Repeater interference on AO-92
I am in the area of a suspected repeater. Also in the area of the towns mentioned to could be that machine. I'll watch for the next AO-92 pass and announce my call of the repeater a few times and listen to AO-92. So if you hear "KV1J" it is me testing for the interference. I have not looked at the pass schedule yet but I can try a couple passes. 73, Eric KV1J FN42
I don't know if it was mentioned, once the receiver is opened with a 67Hz tone AO-9n does not need to hear a tone with any transmission until the one minute timer passes at which time the repeater TX stops. Hearing a tone with each transmission resets that timer, but it is quite possible to make a QSO or cause interference during the one minute without having the tone on your uplink signal. A repeater output or whatever other source of an unexpected signal such as a harmonic, could be heard and repeated if it had better than ~ -120 dBm signal at the satellite during that time.
Jerry Buxton, NØJY
On 4/28/2020 22:17, Eric Williams via AMSAT-BB wrote:
I ran the experiments for 2 passes. 28Apr 1608 UTC and 29Apr 0245 UTC. The first pass was just a few minutes before it switched to the video mode. The second pass was high elevation and 11 minutes.
It was mentioned that the interference might be from a 145.110 MHz repeater due to the 3rd harmonic. Also mentioned were towns heard in the conversation and that there was a courtesy beep. A repeater in our area that fits all those items in the N1CON repeater in Concord MA.
For both passes I heard the bird fine and there were ongoing QSOs. During the passes I transmitted periodically on the repeater announcing my call and 'testing' to cause some audio on the repeater. Also had another station transmitting on the repeater. Throughout the test I did not hear any interference on the downlink. So also, I did not listen to the uplink frequency since there did not seem to be any interference at that time. I am using different radios for TX and RX, and antennas that are far apart for the tests.
I'll check from time to time listening to the downlink. If I hear the interference, I can both check the uplink frequency and also listen to the local repeaters. There are many in this area.
73, Eric KV1J FN42 (West of Boston MA)
-----Original Message----- From: Eric Williams [mailto:[email protected]] Sent: Tuesday, April 28, 2020 11:14 AM To: '[email protected]' [email protected] Subject: RE: Repeater interference on AO-92
Yes, I am also listening to the uplink freq. Next pass is in about 1 hour. 73 Eric KV1J
(I use digest mode for this list so pardon the not including the string of messages)
-----Original Message----- From: Eric Williams [mailto:[email protected]] Sent: Tuesday, April 28, 2020 10:51 AM To: '[email protected]' [email protected] Subject: RE: Repeater interference on AO-92
I am in the area of a suspected repeater. Also in the area of the towns mentioned to could be that machine. I'll watch for the next AO-92 pass and announce my call of the repeater a few times and listen to AO-92. So if you hear "KV1J" it is me testing for the interference. I have not looked at the pass schedule yet but I can try a couple passes. 73, Eric KV1J FN42
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participants (2)
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Eric Williams -
Jerry Buxton