CDM CDM-1550 Speaker question

[KenFL9]

Twenty some odd years ago I acquired a surplus VHF high band CDM-1550 in excellent condition that had been used as a base station mounted in a case with a 110V power supply. I finally retrieved it from storage last week plugged it in. Everything appeared to be working but there was no audio. I took the front panel off the radio and right away saw the problem - no speaker! It does not look like there was ever one there. There was no external speaker with it when I got it, and the accessory plug in the back only has one connection for what I assume is the ignition sense wire.

I don't have any of the manuals to consult, so I am looking for suggestions on the pin outs and resistance for an external speaker or if there is an easy way to put an internal speaker back where one should be?

Thanks!

 

[mmckenna]

Pinout on those rear 20 pin connectors is a bit weird, it's designed around the standard 16 pin connector with 2 extra pins on each end, which throws off the numbering.

https://batlabs.com/images/cdmacc.gif

This link will have the pinout and show the connector.

HT750/1250/1550/PRO5150/7150/9150/GP320/340/360/380/ GP318/338/GP640/680/1280/CDM750/CDM1250/CDM1550,etc.

Pin 1 = Speaker -
Pin 16 = Speaker +

You can buy connector kits on e-Bay that will have everything you need, including wires with the pins already attached you just stick in the back of the existing connector that has your ignition sense pin in it.

Kit 3 Accy Plug 16 Pin Motorola Maxtrac GM300 Repeater | eBay

Accessory Plug Wiring Kit for Motorola radios using a 16-pin rear connector, i.e.: Radius, Maxtrac, GM300, M100 & M200 Series, M1225, SM50, SM120. AMP parts found in Motorola kits. This kit includes .

www.ebay.com