Icom 7610 dual receiver with no RX antenna performance demonstration
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- Опубліковано 20 сер 2024
- I was setting up for a RX antenna video [coming] I noticed that I was receiving signals on the RX antenna port on the SUB receiver, although there was nothing connected to it. I investigated and called Icom and spoke with Rick. He stated this is normal. Anyways, enjoy the demonstration. DE W5DPH 73
The leakage is many dBs down, not looked for the same issue with my FTDX101MP but it is likely to be similar.
Same here on my 7610.. Sometimes S2-3 with strong(er) signals.
Disconnect the RX antenna coax at the back of the radio and see if it stops. You said that the RX antenna was grounded on that switch, I suspect the ground is picking up the signal now... I'm curious what the result is. 73.
Excellent point. When setting up for this video, I did just that. I was getting my radio setup to track frequencies and familiarizing myself with the main, sub and antenna switches. That's when I noticed the bleed over, with no antenna connected to the RX port. Coax hooked up and grounded seemed to make little if any difference. Once on my 7300, I listened to an 80m net without an antenna hooked up. Of course only stronger signals came through but that illustrates even further the sensitivity of these radio receivers.
Stray RF
looks like the isolation is only about 30 dB. Could be an issue if you are using a lossy rx antenna - which is an accebtable technique. Was the pre-amp off also on the RX antenna?
The pre-amp was off.
Try the RX antenna with the 7610 internal pre-amp ON on the RX antenna.... That might help, depending on where, in the 7610 front-end, the leak-across is happening.
Also try "IP+" on, on the main antenna, and/or reduce the RF receive-gain on the main antenna