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<body class='hmmessage'><div style="text-align: left;">I need a little help or ideas on what to try next.<br><br>I had what I thought was a good idea of using an old astro saber for<br>the receiver of my repeater. It is pretty sensitive (.13 uV) and dual mode<br>P25 IMBE. Just wanted to see if it would work as a couple of us have<br>them around here and it would be a crude attempt to integrate asterisk and P25.<br>Granted the transmiter it still FM, but you do gain a little on the RX in the fringe<br>area with P25. I had a spare mic (old coil tube), a battery eliminator, <br>and the proper coax adapter. I spliced into the speaker/mic cable and took the<br>speaker audio into the usb fob. No COR or PL detect available(it may be<br>on one of the pins on the back but I have no manuals). It is speaker audio not <br>discriminator and filtered of PL/DPL. I tried using DSP but it will keep the tx keyed<br>and shows rxsquelch level of 1000 even with the squelch closed. I tried opening <br>the squelch and then locking it open while adjusting the audio and started getting the rxsqlech <br>level to drop. Once I got it under say 700, No amount of adjusting levels and tweaking <br>of the rxvoice and rxnoise levels by hand our auto adjust would give me "good" audio <br>its all HIGHLY distorted and is either noisy or clipping as well. If I just ignore the squelch<br>and let the transmitter stay keyed, I could get some great audio, but the rxsquelch level<br>is at 1000 in DSP and doesn't close the software squelch. I tried VOX mode, but it stays <br>constantly keyed, or will start kerchunking itself off and then back on. In adjusting the <br>levels I can get good audio but can't get the DSP or VOX to react properly. <br>I assume they are trying to calculate S/N ratio but there is no good compromise between level it likes for squelch <br>noise and then the voice level that is then associated with it. I did try playing with the usbradio.conf and changing the<br>rxdemod=no, then speaker, then flat. no option worked. I got best audio with it on speaker, but the transmitter stays constantly keyed.<br><br>I tried a cap to eliminate any DC and a 1:1 transformer on the speaker mic audio into the usb fob. I can detect no 60hz groundloops<br>and I used a hound sniffer and then hooked up some headphones to the output of the receiver and don't hear any hiss.<br>I would like to make this work but its not looking good so far. <br><br>Don<br>W9DRR<br><br><br></div><br /><hr />Want to do more with Windows Live? Learn “10 hidden secrets” from Jamie. <a href='http://windowslive.com/connect/post/jamiethomson.spaces.live.com-Blog-cns!550F681DAD532637!5295.entry?ocid=TXT_TAGLM_WL_domore_092008' target='_new'>Learn Now</a></body>
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