Hi Jim,
The part of the mod in question is the fact that logic from the OEM PL decoder goes to the Micor Squelch Chip on the A&S board and when the receiver is decoding PL, forces the squelch open *without regard* to the carrier squelch setting. Since ham radios don't have reverse burst, cutting this logic line separates the COS and PL signals so they operate independently; which removes the squelch burst at the end of a transmission when a user is encoding PL without RB. This is done by cutting jumper JU204 on the A&S board; as you have found. So, you see, that's what reverse burst has to do with it, because if all ham rigs had reverse burst, we wouldn't have to cut JU204. As a comment to Jim and anyone else, I used the PL disable switch and the transistor associated with it (on the station control card) as the F1 channel element switch. That way I have a positive tx disable on the front panel-with an idiot light that comes on when disabled. The switch grounds the base of the transistor, and keeps the F1 transmit element from coming on. That's one way of doing it, however there are times where we modify Stations and want to use the PL Disable switch as intended; so I do it a bit differently, to accomplish the same result: <http://www.repeater-builder.com/rbtip/stationcontrol.html> Kevin Custer Yahoo! Groups Links
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