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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?

Postby g8tzl2004 » Thu Aug 03, 2017 2:26 pm

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?

Postby kcbooboo » Fri Aug 04, 2017 4:36 am

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?

Postby Bill_G » Fri Aug 04, 2017 4:53 am

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?

Postby g8tzl2004 » Thu Aug 10, 2017 7:57 am

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?

Postby n1gtl » Thu Aug 10, 2017 2:02 pm

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?

Postby kcbooboo » Thu Aug 10, 2017 3:43 pm

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.

Bob M.

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

Postby Winger2002 » Sat Aug 12, 2017 5:17 am

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?

Postby SteveC0625 » Sat Aug 12, 2017 7:23 am

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?

Postby thebigphish » Wed Aug 23, 2017 7:08 pm

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
"How do you plan to outwit Death?"
"With a knight and bishop combination; I will destroy his flank.
" --Antonious Block


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