cdm1250 pa

jmr3865 · Post by **jmr3865** » Sun Dec 25, 2005 5:56 pm

how do you program the cdm1250 to be used as a p.a?

HLA · Post by **HLA** » Mon Dec 26, 2005 12:30 am

i don't think that's possible but you can take the audio line out of it and wire it into you siren.

thebigphish · Post by **thebigphish** » Mon Dec 26, 2005 8:08 am

but that will just give you radio rebroadcast, rather than true public address function. any audio generated locally will not be heard by the speaker.

HLA · Post by **HLA** » Mon Dec 26, 2005 12:59 pm

sorry i wrote that wrong, i've never done this before but pin 2 on the back connector is the mic pin, see if that will feed your siren box. like i said i've never tried it but maybe someone else has?

jmr3865 · Post by **jmr3865** » Mon Dec 26, 2005 1:00 pm

what about radio rebroadcast?

Will · Post by **Will** » Mon Dec 26, 2005 1:29 pm

"what about radio rebroadcast? "

Same as EXTernal SPeakR. The external speaker pins are wired thru a protection circuit to the Public Address amplifier.

REMEMBER, the CDM and other radios use a "bridge" audio amplifier circuit and the speaker leads can NOT be grounded to anything. Both speaker leads are 'HOT'. Grounding or hooking a speaker lead to the wrong thing will burn out the audio PA chip in the radio.

jmr3865 · Post by **jmr3865** » Mon Dec 26, 2005 2:16 pm

how do you program it though in cps and enable it?

nmfire10 · Post by **nmfire10** » Mon Dec 26, 2005 2:26 pm

The CDM can *kinda* do a PA mode. It isn't really a PA in the traditional sense though. There is a PA Switch input on the accessory connector. When you enable this input via an external switch, it will send your microphone audio to the external speaker hooked up the radio. When I say external speaker, I mean the same speaker that your radio receive audio comes out of.

I can not for the life of me figure out what the purpose of this could possibly be. Why would you want to talk to your self??

jmr3865 · Post by **jmr3865** » Mon Dec 26, 2005 2:28 pm

is it different from radio rebroadcast?

nmfire10 · Post by **nmfire10** » Mon Dec 26, 2005 2:56 pm

Radio rebroadcast is a function of a siren. It takes an audio intput from your radio and plays it out over the siren speaker.

This is all CDM. All it does is make your microphone audio come out of the external speaker connected to the radio. The same speaker that your receive audio comes out of. If you don't have an external speaker and still use the one on the control head, it does nothing.

jmr3865 · Post by **jmr3865** » Mon Dec 26, 2005 3:56 pm

I would need a siren that has radio rebroadcast then. Thank you very much for all of your information.

** Uh oh, I said siren on the batboard w/ no sirens allowed. I hope this thread also has enough about radios or it will be locked!

(sorry, I had to).

Thanks again for all the info

nmfire10 · Post by **nmfire10** » Mon Dec 26, 2005 8:39 pm

I suppose if you had the radio's external speaker hooked up to the siren's radio re-broadcast input, it would make the radio mic audio go into the siren and out the siren speaker. But that is double redundant. The siren has a PA already. Plus the CDM does not mute the RX audio while it is in PA mode. You get the mic audio (PA) and the RX audio at the same time. The whole thing is a waste of effort.

Let the siren be a siren and a PA like it is supposed to be. Let the radio be a radio like it is supposed to be.