Page 1 of 1

CDM1550 control head potentiometer

Posted: Fri Jun 09, 2006 8:05 pm
by 486dx4
Hi,

I have a part number for the control head potentiometer for a CDM1550 as 1805911V01 from the parts manuals in PDF format that came from links on this site. But when you look at the CDM1250/750 mobile the potentiometer for the control head is 1805911V02. The online ordering places do not come up with the V01 part number but they all have the V02 number.

Is the pot different for the 1550 than for the other waris mobiles? Or can I use the the V02 pot? If not, then I guess I have to call motorola?

What I am looking for really is the shaft that kind of rides on the pot to allow you to power up the radio and work the volume. The pot itself is ok.... I assume ordering the pot will get you that as well?? or is there another number for that??

Posted: Sat Jun 10, 2006 7:54 am
by jackhackett
As far as I know the pot should be the same as the 750/1250, but I haven't had to replace one on a 1550 yet so I suppose it could be different.
I believe there's one pot with a number that ends in V01 that looks the same as the 1805911V02 except that it's not push on/off, instead you turn the knob. The best thing to do would be to just look at the knob in your radio, it will have the part number printed on it.

There are 3 pieces to a CDM volume control, the pot/switch, the knob interior (white plastic inside portion of knob) and knob exterior (black rubber outer portion of knob). If by shaft you mean the metal shaft that sticks out of the pot, that is not a separate piece, if it came out the pot is broken.

Posted: Sat Jun 10, 2006 9:17 am
by 486dx4
Yes - I am looking for the metal shaft that sticks out of the pot. Its a shaft with three tabs that seems to "ride" on top of the pot. Initially the radio came with no power/volume knob so whoever had it before was using the radio with no knob. The shaft was "very loose" but the radio did power up and the volume did work, etc. However, the radio did not always power up when pressing the knob but eventually it does do it. SO you are saying the shaft does stay on the pot and should not have been able to been removed - it just came off when I took things apart... I guess I'll have to call Motorola and order the right part....

Re: CDM1550 control head potentiometer

Posted: Thu Feb 11, 2010 8:36 am
by dispatcher7586
I am having the same problem. The pot shaft is broken. Its in two now. I called 2 motorola dealers/depots and according to them, the parts not available/cancelled. Motorola wants you to go to a motorola depot and buy an entire new control head for $240.00, or send it in to Motorola for repair for $300.00

Im looking at a cdm750 control head. Has anybody ever took a cdm750 potentiometer and shodered it onto a cdm1550?

Anybody have a spare cdm1550 potentiometer?

Thanks...

Re: CDM1550 control head potentiometer

Posted: Thu Feb 11, 2010 5:31 pm
by RadShop
The reason you're getting told it's not available, is that it doesn't "pay" to supply people with only parts. When you consider handling, time spent on the phone, the margin for the part just isn't there.

With that said, I have a case of 250 of these in stock.

I can probably sacrifice a couple 8)

Re: CDM1550 control head potentiometer

Posted: Thu Feb 11, 2010 6:18 pm
by AEC
The pot is available from MOL, I replaced several of them already.

You have to buy a supply of them in order to make it worthwhile, but the control is a P.O.S for the CDM series(all the same).

This part is held together by a few lugs, folded around, and under the body, and never have I found one that will not come apart with simple bending.

Actually, the metal body of the pot is retained by the fingers of the upper assy. It's one piece and the three 'fingers' are clamped to the lower assy, and held by glue/epoxy.

Poorly made control, and NOT suitable for use in the radio.( my take on this component's quality)

There are two solder tabs and three 'pins' that solder through the board vias.

Control shaft housing may be olive drab(OD) green, with the lower body being black plastic, with white printing on it.

http://img153.imageshack.us/img153/1170 ... 191500.jpg <-----This is what you are looking for

Re: CDM1550 control head potentiometer

Posted: Thu Feb 11, 2010 11:25 pm
by dispatcher7586

Re: CDM1550 control head potentiometer

Posted: Fri Feb 12, 2010 9:26 am
by 35echo
486

1805911V02 subs to 1805911V02 subs to 1866500A01 subs to 1866500A02.

1866500A02 POTENTIOMETER PUSH ON-OFF $55.50 for a package of 10

Its not sold by 1 each anymore.

Regards,

Allen

Re: CDM1550 control head potentiometer

Posted: Fri Feb 12, 2010 9:38 am
by AEC
I see the problem, it broke apart....

See this quite often, this control is 'weaker' by its design, and can't take any abuse(downward pressure on the button) without being stressed to the point of
breaking the adhesive which makes the body loose and eventually comes apart.

Re: CDM1550 control head potentiometer

Posted: Fri Feb 12, 2010 10:37 am
by dispatcher7586
AEC wrote:
I see the problem, it broke apart....

See this quite often, this control is 'weaker' by its design, and can't take any abuse(downward pressure on the button) without being stressed to the point of
breaking the adhesive which makes the body loose and eventually comes apart.
Yes and now since its broken, I have to put the top potentiometer part on and reassemble the base and control head and push the push button down (bending it downward) for the radio to function.

Re: CDM1550 control head potentiometer

Posted: Fri Feb 12, 2010 2:40 pm
by AEC
You could try reassembling the two sections, and apply pressure to the tabs on the upper section to force them to grab the lower body of the control a little tighter, and place a TINY drop of superglue near the three tabs and use a piece of wire or ty-rap to hold the pieces firmly until the adhesive sets.

This is NOT a permanent solution, only a temporary 'fix'.

Re: CDM1550 control head potentiometer

Posted: Fri Feb 12, 2010 8:07 pm
by dispatcher7586
AEC wrote:You could try reassembling the two sections, and apply pressure to the tabs on the upper section to force them to grab the lower body of the control a little tighter, and place a TINY drop of superglue near the three tabs and use a piece of wire or ty-rap to hold the pieces firmly until the adhesive sets.

This is NOT a permanent solution, only a temporary 'fix'.
Thanks, I tried that. I used small hair rubber bands. I but the piece in, lined it up and tied the rubber bands around the 3 clamps on the top piece. Then I secured more rubber bands around the entire board and ran them on both sides of the shaft. It was working for a while, until the rubber bands broke. Im just looking to replace the pot.

Re: CDM1550 control head potentiometer

Posted: Mon Feb 22, 2010 10:13 am
by cwolf520
OK, I have the part number for the pot as 1866500A02 which is a 10 pack of pots (a little pricey!). That is good cause I got a bunch of 750 and 1250's that need fixing. These guys are so tough on these radios!

Now I have a part number for the knob as 3686098B02 according to a PDF from Wiscom. I typed that number into moto-online and it does say it is a knob. Do I need still another piece (white insert) to make the knob attach to the pot? If anybody has those part numbers, I would be grateful.

http://www.wiscomm.com/MotoCatalog/CDM7 ... DM1550.pdf

Also, anybody have the part number for the deluxe service manual? That should tell me all the part numbers of anything I could possibly need.

My big problem is removing the pot without destroying the PCB. Did the first one without destroying the board. Motorola in their infinite wisdom decieded to ground one of the leads and if anybody knows how tough it is to get solder off of a ground plane, it is tough.

Weller pencil, solder sucka, solder wick and a peice of antenna with a sharp point.

My NASA Soldering instructor is rolling over in her grave!


Thanks for any info

Chuck
KC2QPD