Batboard

I cannot get the receive TPL tones to work on a Maratrac. I know they are programmed in for each mode but for some reason it still receives and scans in CSQ. Any help is appreciated.

Is the mic hanger grounded? If not, receive subtone no workee. Also from your description, I'd say csq scan is enabled in the RSS at the HUB switch option in Scan Options which is why it will scan when the mic isn't grounded. For the uninitiated, this mic grounding thing is designed to help you to conform to the FCC reg that you monitor the channel before transmitting, so the receive subtone works only when the mic is hung up in the grounded mic hanger. The problem with that thought line is when the radio system has no other users and no other subtones in the coverage area, there's no need to do that monitoring thing, and it makes normal usage annoying when you really don't want or need that csq revert crap going on when you come "off hook."

The blue wire in the mic circuit is the one that needs to sense chassis ground, BTW. To defeat the "off hook" phenomenon, I use pin 35 (HUB) on the VIP plug to go to chassis ground. You can also jumper pin 35 to a ground in the control head, but I find that there's less tendency to get alternator whine in the receive audio if you just duplicate the mic ground by going to a good external ground.

That makes perfect sense to me now. It would have taken me quite a while to figure it out.

Thank you very much for your help.

One of the kinda sucky things about the Maratracs is that the mic ground/HUB function can't be completely disabled in programming like a Spectra. It has to be set either to Scan Disable or Monitor. I modded a mic internally for a friend of mine that had one to disable HUB, but the above-mentioned mod will also work.

You can tie the blue wire (HUB) to the black wire (mic lo) in the mic, but there's the possibility of alternator whine in the receive audio when that's done since that's not intended to be the HUB reference. Low band units are more likely to produce the whine than UHF or VHF high band units, but all will to some degree. The whine should reduce as the battery's charge condition nears full charge.

I got it working thanks to you guys. I tapped pin 35 on the VIP and ran it to chassis ground and it is working great.

Thanks again.

very simple solution to all of this is to jumper pin# 35 to pin# 36 on the back of the vip connector. just make a 2" jumper wire using the proper pintips, crimp properly, and insert. i have done over 1000 of these and the only problem is not properly crimping, so the pin isn't uniform diameter sliding into the connector easily. (it's so simple, a batman could do it) lol