CDM1250 TPL Problems

[kd8fre]

Ok, I am new to the board, but have been working with radios for quite some time, and this one has me baffled.

I have a 136-174 MHz CDM1250 that is programmed for a Repeater with a 100Hz TPL tone. We are able to key the repeater, but it appears that the TPL being transmitted by the radio is not at a high enough level to keep the repeater keyed.
When listening on a secondary radio, it sounds like the carrier is dropping out. We have turned the tone requirement off on the repeater in a testing effort, and when we do so, we have absolutely no issues keying and using the repeater. We have also tested the radio on a different repeater with a different TPL (131.8Hz), and it works fine there.

Is there a way to adjust the level of the TPL output? Our thought is that for whatever reason, the TPL being output by the radio is not within an acceptable range for the repeater.

Does anyone else have any other ideas as to what may be causing this issue?

Thanks,
KD8FRE

[Jim202]

Ok, I am new to the board, but have been working with radios for quite some time, and this one has me baffled.

I have a 136-174 MHz CDM1250 that is programmed for a Repeater with a 100Hz TPL tone. We are able to key the repeater, but it appears that the TPL being transmitted by the radio is not at a high enough level to keep the repeater keyed.
When listening on a secondary radio, it sounds like the carrier is dropping out. We have turned the tone requirement off on the repeater in a testing effort, and when we do so, we have absolutely no issues keying and using the repeater. We have also tested the radio on a different repeater with a different TPL (131.8Hz), and it works fine there.

Is there a way to adjust the level of the TPL output? Our thought is that for whatever reason, the TPL being output by the radio is not within an acceptable range for the repeater.

Does anyone else have any other ideas as to what may be causing this issue?

Thanks,
KD8FRE

Sounds like your in need of putting that radio on a service monitor. There is no adjustment just for the PL level
output on the radio. You may have other problems. Being off frequency can cause an issue. If the mic audio
deviation is set too high, you will chop in and out of the radio as you talk. Being off frequency can cause the
same problem.

Try this, if you key the radio up without saying anything, does it hold up the repeater solid?

If you pass step one, then try holding the mic about a foot away and talking. Does it hold the repeater up, but
only sound very low in audio?

Bring the mic closer and try it again. My bet is that your dropping out or chopping into the repeater as your
mic level comes up. Problem is I can't tell you if it's off frequency or too much deviation.

There is the possibility that the repeater receiver is off frequency. If everyone is having the same issue, that
is where I would start. If it is only one radio user having the problem, then I would go look at that radio.

Here is where it is nice to have a radio tech in the club that can have a service monitor available to check out
the problem.

Jim

[Bill_G]

Agreed. Put a service monitor on it and check the 100hz PL. It may not be 100hz.

[HLA]

is the problem specific to just this one radio?

[kd8fre]

Thanks for the replies, to answer a couple of you:
If we key up without saying anything it does not appear to key the repeater at all, we get nothing on another radio listening to the repeater, and no repeater tail after we un-key.
Yes this issue is specific to this one radio, we have multiple other brands and models of radios operating on this repeater with no issues.
If we are able to put it on a service monitor and discover that the TPL is off, how do we fix that, or does it have to be done by a Moto Tech?

KD8FRE

[jackhackett]

If it works on the 131.8 PL repeater then the odds are the PL frequency is okay.

You didn't say what bandwidth the radio and repeater are programmed for. Trying to use a CDM programmed for 12.5KHz on a repeater set for 25KHz can cause the problem you describe. Some repeaters will work with a lower PL level than others, which could explain why the 131.8 repeater keys okay.

Check the bandwidth setting on the channels in question to make sure it is correct for your system.
Other than that you're going to need to check it on a monitor.

[kd8fre]

Thanks for the reply, I am going to check the bandwith on both tomorrow and see if that solves it.

KD8FRE