CDM1250: Lowering Power Ouput

[tmtu]

I have a UHF (403-470) CDM1250 mobile that I'm trying to convert a vehicular repeater.

I am aware of the low power setting in the CPS... The lowest I can put is 20 watts.

Is there a way I can lower the RF output to around 1-2 watts?

Thanks for the ideas.

[HLA]

no, they won't go that low, they wouldn't even like to go down to 10 watts.

[escomm]

What? I have no problem going to the Radio Configuration -> TX Power tab and setting the power all the way down to 10 watts. I have done this on a CDM1250 and CDM1550LS+ used in a base station setting at 12 watts. CPS lets me go all the way to 1 watt.

I would not recommend turning the power down to 2-4 watts, although I have seen it done by others.

[Hightower]

Weird, my CDM1250 low setting only goes from 20 to 54 watts. I wonder if firmware or cps versions dictates how low the radio will go?

[VE9MP]

Must be some differences between firmware or CPS releases?
CPS 6.04 allows me to go right down to 1 watt, with the all the different CDM1250's and a 1550 I have kicking around, on both VHF and UHF models

[HLA]

when you take the low limit down below 20 it jumps back up to 54 and when you enter a number lower than 20 manually it won't take it. i'm using the newest 6.09 cps and the newest firmware right now but i've had this happening for a long time that it wouldn't let me go below 20. is the cdm you are doing this on a low power 25 watt unit to start with? those will go down to 1 watt but the 45 watters won't do that? i'll bet the model you got that to do that on has a "h" for the 7th digit, the "k"'s will not do that.

[Hightower]

Model # AAM25KKD9AA2AN ---> 7th letter K, and this is a 20 watter on low, but 52 on high.

[wavetar]

It has nothing to do with CPS or firmware. The "low powered" CDM will adjust from 1-25 watts in UHF and I believe 1-30 watts in VHF. The "high powered" CDM will adjust from 20-45 watts (maybe 50 in VHF?). If you need low power, get a low powered CDM...they are better suited than Maxtrac/GM300 style radios as they won't get spurrious when putting out less than approx 5 watts.

Todd

[tmtu]

Thanks for the feedback guys.

Well, I have a high powered CDM1250 (UHF) so that answers my question.

Looks like I'll need to hunt down a low powered version for my purposes.

PS if anyone wants to swap one with me; let me know.

Thanks!

[VE9MP]

It has nothing to do with CPS or firmware. The "low powered" CDM will adjust from 1-25 watts in UHF and I believe 1-30 watts in VHF. The "high powered" CDM will adjust from 20-45 watts (maybe 50 in VHF?). If you need low power, get a low powered CDM...they are better suited than Maxtrac/GM300 style radios as they won't get spurrious when putting out less than approx 5 watts.

Todd

Not being picky Todd, but the UHF CDM1250 we have in service here is variable from 1-30 watts, not 1-25, not that it makes a lot of difference though....