Page 1 of 1
CDM1250--Signalling 'noise' upon Keying up
Posted: Wed May 02, 2012 3:46 pm
by ten13
I recently programmed a CDM 1250, with no signaling involved, xmit or rec, yet I get that 'noise' going out over the air when the mic is keyed up.
Any software solution to this?
Thanks!
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Wed May 02, 2012 9:45 pm
by thebigphish
what's the firmware?
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Thu May 03, 2012 10:44 am
by HLA
what shows up on the display of a recieve radio? Or have you put it on a scope to see what actually is being transmitted? Where did you get the radio, it's possible if it was used that it's got an aftermarket board installed inside it?
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Thu May 03, 2012 10:47 am
by ten13
It was purchased used, coming from, I believe, a fleet. Other than that, don't know the history.
The firmware indicates "unknown."
I've not gotten around to asking anyone what shows up on a receiving radio, but if anything did, I probably would have heard about it by now.
Is it a possibility I will just have to live with it?
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Fri May 04, 2012 3:08 pm
by HLA
firmware will be on a sticker on the back of the radio or plug it in and read the radio and see what the cps shows. i'd open it up and see if there is an options board of some kind installed in it?
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Fri May 04, 2012 7:50 pm
by ten13
The sticker says "version R05.05.05"
For what it's worth, the software shows no Option Board.
I'm reluctant to open the case of this CDM1250, having had some bad "experiences" taking apart some old Maxtracs (besides, I don't see any screws).
As I say, it sounds like an MDC-type of 'noise' when I transmit, but I don't have any Signalling programmed. There are others with this 'noise' on my radio groups, so I'm not really annoying anyone with it (except myself).
If you think that there is, in fact, an Option Board inside the radio causing this, or something else inside, I will search out someone from the groups who has more experience ripping these things apart and see what's what.
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Sat May 05, 2012 10:28 am
by HLA
that firmware isn't real old or ancient but it is possible there is a board in there, just because you don't have one selected in the cps don't mean anything. And the problem you are having with the firmware version in the cps is you're either opening up a codeplug or looking at it after you write to the radio. The only way you are going to see the firmware version in the cps is to read the radio and go directly to the firmware version and look at it. One more thing, are you using this simplex or repeater? And does it happen with tx on both?
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Sat May 05, 2012 3:56 pm
by ten13
Right about the firmware number. I realized that when I looked at it the next time I downloaded the plug.
The radio is primarily used with repeaters, but I put a simplex freq. in and still hear it.
I went to everything in the CPS that said anything about "tones" and "PTT," and unchecked them, and still got the noise.
Thanks for your patience....
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Sat May 05, 2012 4:35 pm
by ten13
Sent an email to the guy I got the radio from, asking him about any option boards installed....
Here's his reply:
yes on some of these units the company that used these radios installed an id board , because they did not used mdc1200 id , they used the star id. it's simple to remove
move it just remove the front face of the unit and you will see it it has 4 wires just be careful went you cut it . if you can't do it i will be more then happy to do it for you 2 not cost to you.
Now, if I can figure out how to take the front face off without destroying the radio, I'll be in good shape (any detailed instructions on how to take the front off?)
Thanks to all...
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Sat May 05, 2012 5:15 pm
by ten13
Final update.....
I called the guy I bought the radio from, and I popped the hood and cut the wires to the added-on board.
All is well!
Thanks to all!
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Sun May 06, 2012 6:57 pm
by HLA
I almost would of left it, star sounds pretty good, it's pretty much useless but it wasn't hurting anything. List the board for sale and maybe you can get some of your money back out of it?
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Mon May 07, 2012 1:18 pm
by ten13
Hmmmm....didn't think there was any 'demand' for the board. It's not much bigger than my thumb nail (well, sort of). I cut the wires, but left the board itself in the head, figuring I would lose it if I left it on my desk.
Frankly, I don't even know what the star system is. I'm just up to being able to program a Motorola for the tones of my volly department.
Anyway, thanks for your help. If you had not brought up the board issue, I would have not known enough to even ask the Seller about it!
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Fri May 11, 2012 5:37 pm
by HLA
one mans junk is another mans treasure. But like I said, it sounds cool and somebody might like it just for that reason, it don't have to actually work, just create the tone programmed in it already
Re: CDM1250--Signalling 'noise' upon Keying up
Posted: Sat May 12, 2012 11:02 pm
by N6LAU
ten13 wrote:Sent an email to the guy I got the radio from, asking him about any option boards installed....
Here's his reply:
yes on some of these units the company that used these radios installed an id board , because they did not used mdc1200 id , they used the star id.
Ah, if only they made a MODAT board. 