CDM 1250 power output

[Thomas]

Hi all...

I've been doing a lot of reading on here and learning a lot. I'm new to Motorola radios, always liked them a lot. I recently purchased 2 used CDM1250 radios and CPS HVN9025 R06.10.02 to use for GMRS. One of the two radios is the high power version. This particular radio, for the first week I had it would only transmit at 25 watts output no matter what I set the power level at in the CPS. No other problems, crystal clear audio on transmit and receive. Tonight while transmitting the output power droped to about 1 watt or less. Its barely moving the needle on a watt meter but still transmitting. There is suffuciant amperage from the power supply and the antenna is connected and has a 1.3:1 swr. It is receiving just fine, no other noticable problems with the radio. Any ideas what could have happened. I'm open to suggestions and would greatly appreciate advise from more experienced users of these radios. Thanks.

[Jim202]

A couple of thoughts come to mind on the low power output of your radio.

1. Look up your model number and make sure you understand what the normal rated power output should be.

2. Take a look at the high current feed wires that connect to the back of the radio at the 2 pin connector.
Make sure you have wires of the correct gauge that the radio needs for the current it should pull.

3. Take a volt meter reading right at the back of the radio while your trying to transmit. It should not go
below 12 volts at a minimum. Better to see 13.5 or so. If it's low, find out why. If it's good you probably
have a blown PA in the radio. Might try measuring the current pull on this wire. Check the fuse connections.

4. Make sure you have RF connectors made up properly. Many people tend not to solder the center pin
of the mini UHF connector on the coax that is on the back of the radio. This connector also tends to
work it's way loose. Make sure it is tight.

That's about the limit of suggestions without some more feedback from you.

Jim

Hi all...

I've been doing a lot of reading on here and learning a lot. I'm new to Motorola radios, always liked them a lot. I recently purchased 2 used CDM1250 radios and CPS HVN9025 R06.10.02 to use for GMRS. One of the two radios is the high power version. This particular radio, for the first week I had it would only transmit at 25 watts output no matter what I set the power level at in the CPS. No other problems, crystal clear audio on transmit and receive. Tonight while transmitting the output power droped to about 1 watt or less. Its barely moving the needle on a watt meter but still transmitting. There is suffuciant amperage from the power supply and the antenna is connected and has a 1.3:1 swr. It is receiving just fine, no other noticable problems with the radio. Any ideas what could have happened. I'm open to suggestions and would greatly appreciate advise from more experienced users of these radios. Thanks.

[Thomas]

Thanks for the suggestion, I will verify them all. I have already verified the model number of the radio as the high power option, confirmed by having to write a new code plug for this one after I wrote the low power units codeplug, tried to load it in the high power unit and it would not take it due to the model number difference. The power cord is the facotory /\/\ unit. I will measure the voltage at the power connector and check the RF connections. Mabey I'll get lucky.

Also, If I have to send this to /\/\ for repair will the CPS version (HVN9025 R06.10.02 ) I have work when I get it back? I've read that /\/\ does firmware updates to radios as part of the flat rate repair service. If newer firmware is installed can it make the CPS I have useless for this radio. Thanks again for helping a /\/\ newbie.

[Jim202]

I would try everything till your out if ideas before considering sending the radio back to the Mother land. I
don't have the current rate sheet, but it's some place around $300 to $400 for the flat fee.

Sending the radio back will cost you the flat fee. It will also cause the radio to come back with the current
firmware version as well as the current CPS version. I believe that the current CPS is R06.07.04. If you
don't have a current subscription to the CPS, then your going to be out of luck programming the returned
radio.

Jim

Thanks for the suggestion, I will verify them all. I have already verified the model number of the radio as the high power option, confirmed by having to write a new code plug for this one after I wrote the low power units codeplug, tried to load it in the high power unit and it would not take it due to the model number difference. The power cord is the facotory /\/\ unit. I will measure the voltage at the power connector and check the RF connections. Mabey I'll get lucky.

Also, If I have to send this to /\/\ for repair will the CPS version (HVN9025 R06.10.02 ) I have work when I get it back? I've read that /\/\ does firmware updates to radios as part of the flat rate repair service. If newer firmware is installed can it make the CPS I have useless for this radio. Thanks again for helping a /\/\ newbie.

[escomm]

Current CPS is 6.10.04 and as far as I know it does not change the codeplug version so you should be OK with 6.10.02