Batboard

Hi All - We have an issue with a newly installed CDM750 - when using the rear accessory connector to key the radio, it seems to strip PL, however, the front microphone works just fine.

We're using this radio to transmit DTMF tones that another device produces, to be received across town.

We did not have the luxury of a service monitor today to actually verify what's going on, but had to rely on a "receive" light on the far end. (no speaker in this unit, only the LED).

When we key the CDM750 with the front (standard) microphone, the "receive" light at the device illuminates properly. However, from the rear accessory connector (wired for PTT, mic audio, ground etc) there is no receive light at the far end. To further complicate things, from the rear accessory connector, the radio does actually transmit what it's supposed to, albeit carrier squelch it seems - I can hear the traffic/audio on my scanner. But without PL, our other device ignores the transmission.

I opened a case with tech support and emailed them my codeplug. I'm just wondering if anyone had any ideas in the meantime.

b18c_ej8 wrote:Hi All - We have an issue with a newly installed CDM750 - when using the rear accessory connector to key the radio, it seems to strip PL, however, the front microphone works just fine.

We're using this radio to transmit DTMF tones that another device produces, to be received across town.

We did not have the luxury of a service monitor today to actually verify what's going on, but had to rely on a "receive" light on the far end. (no speaker in this unit, only the LED).

When we key the CDM750 with the front (standard) microphone, the "receive" light at the device illuminates properly. However, from the rear accessory connector (wired for PTT, mic audio, ground etc) there is no receive light at the far end. To further complicate things, from the rear accessory connector, the radio does actually transmit what it's supposed to, albeit carrier squelch it seems - I can hear the traffic/audio on my scanner. But without PL, our other device ignores the transmission.

I opened a case with tech support and emailed them my codeplug. I'm just wondering if anyone had any ideas in the meantime.

I think that without seeing the codeplug, most of us would be flying blind to try to answer your question.

Can you confirm that the accessory connector pins 6,8,12, and 14 are NOT programmed to strip tx PL?
Can you tell us the firmware revision currently installed in the CDM750?