LiveATC Discussion Forums
Air Traffic Monitoring => Listener Forum => Topic started by: TonyP123 on March 15, 2013, 08:01:50 AM
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Well, I don't know long this has been the issue on the feed. I noticed the multiplexer for my antennas took a dump. It's been introducing a hum into the radios, to which it's being transmitted into the feed. I pulled it out of the antenna line and made a direct connection to the receiver. I will try to improve my signal to my radio by duplexing another antenna to the radio as a band-aid ...1dB increase would make my happy.. Weekend project.
I have also added a noise filter into the audio cable between the radio / computer. This should have adjusted my audio unbalance between the two. I will work on tweeking the filter this weekend. Built a 50 dB PAD filter and I will replace the fixed value resistors with a var-resistor. If I can get rid of the hiss, I will do cart wheels. lol
Thanks to the KISM listeners for you patience. :-)
tony
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Thanks Tony!
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Tony - Good luck on the hiss, but I think the real problem is that your receiver just has a poor squelch gate. Anything that filters that out is going to make the desired audio sound like it's going through a sock. Only solution is either modify the rig or brew up an external squelch, which would be pretty easy... one quad op-amp and a handful of resistors and caps. Could tailor some nice audio, too. Sounds to me like you have two different receivers... what's the setup?
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The main radio is an AOR AR5000 kinda over kill for this task. I have it connected to a SCANTENNA .
One of the secondary radios I have is a Uniden 780XLT...which BTW is an excellent VHF radio but has been made obsolete on our police trunk (rebanded).
The best part of the AR5000 is its' built in filters of 5 different settings relating to the audio characteristics.I also have available the Audio De-emphasis feature. I don't use it much but did turn it on as of this recent issue I have.
I was able to make adjustments to the I.F bandwidth. I have it set to 6kHz . I'm not sure if I like the way it sounds.