CDM1550s without heads - can they be used for a repeater?

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g8tzl2004
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CDM1550s without heads - can they be used for a repeater?

Post by g8tzl2004 »

Can I use 2 CDM's with no control heads to build a simple repeater? Or do I need the control heads for repeater operation?

If I don't need control heads, can I use 2 bodies which also have no remote head interface units" ie with the flex cable just dangling out of the radio body!!
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kcbooboo
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Re: CDM1550s without heads - can they be used for a repeater?

Post by kcbooboo »

Not sure if the radio requires the control head to pass self-tests.

Probably safer to pull the flex cable out of the radio and leave it attached to the control head.

Bob M.
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Bill_G
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Re: CDM1550s without heads - can they be used for a repeater?

Post by Bill_G »

The quick way to find out is if you can read/write to them with the RSS. If yes, then your repeater question *may* be the same.
g8tzl2004
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Re: CDM1550s without heads - can they be used for a repeater?

Post by g8tzl2004 »

Can you program a CDM from the rear accessory socket?

If not, I guess I will need a head attaching to program the radios and to program in "power up on applying 12v" etc
n1gtl
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Re: CDM1550s without heads - can they be used for a repeater?

Post by n1gtl »

You can program a CDM from the rear 16 pin connector. I'm curious how you're going to turn it on with no power button. Sure, the ignition pin MAY work. I program two piece APX radios all the time without connecting the control head, I just don't know if what you want to do will work. Please follow up when you figure it out.
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kcbooboo
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Re: CDM1550s without heads - can they be used for a repeater?

Post by kcbooboo »

According to the service manual, the radio CAN be programmed to turn on and off with IGNITION voltage and it CAN ignore the ON/OFF switch on the volume control. But you have to be careful when playing with that programming because you could get the radio in a state where it can't be turned on with either method, then you've effectively bricked the radio as soon as you write the code plug to it.

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Winger2002
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Re: CDM1550s without heads - can they be used for a repeater?

Post by Winger2002 »

Program ignition sense and you should be good! If you can get the brick side remote head adaptor you can program through that instead of having to screw with the rear accessory cable.
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SteveC0625
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Re: CDM1550s without heads - can they be used for a repeater?

Post by SteveC0625 »

Head or no head doesn't matter. If you program it for Ignition Sense Only, sooner or later you won't be able to fire it up at all.

Program it for On/Off AND Ignition Sense, and you're on much safer ground for the long run.
thebigphish
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Re: CDM1550s without heads - can they be used for a repeater?

Post by thebigphish »

this EXACT thing happened to radios that were programmed to follow IGN only, and then had the batteries die in the chassis of the (poorly) designed unit. Mobile radio would give you low-power beep and become functionally useless. Pulling fuses and charging chassis batteries would fix it
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