Weird Spectra wiring

The General forum is where users can discuss any topic regarding Motorola communications equipment - hardware, software, etc. There are also several focused forums on this board, so please take the time to ensure that your questions doesn't fall into one of those categories before posting here!

Moderator: Queue Moderator

Weird Spectra wiring

Postby fchrist16 » Mon May 17, 2010 8:50 pm

Alright guys...

Who's come across this before on a command board? The wires are coming off the resistors are yellow/orange at the top, blue/green in the middle and the one lone red wire on the left. No RX audio off the radio and the TX audio is a quick scratchy sound and then drops. All the caps are brand new, as evidenced on the command board...

Image

Ideas?

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby Bill_G » Mon May 17, 2010 9:25 pm

eew. ouch.
User avatar
Bill_G
 
Posts: 2520
Joined: Thu Sep 17, 2009 5:00 am
Location: Portland, OR

Re: Weird Spectra wiring

Postby fchrist16 » Mon May 17, 2010 9:33 pm

Care to elaborate. Obviously it must not be good...

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby Bill_G » Mon May 17, 2010 10:12 pm

It may be recoverable, but I suspect some custom mods have been attempted. Got another cmd brd? Or a way to rework this one?
User avatar
Bill_G
 
Posts: 2520
Joined: Thu Sep 17, 2009 5:00 am
Location: Portland, OR

Re: Weird Spectra wiring

Postby fchrist16 » Mon May 17, 2010 10:17 pm

Negative on the command board and I'm not sure how exactly I would rework it...

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby Tim » Tue May 18, 2010 10:37 am

The connections are right around U400 - the Audio Filter IC. Also
looks like some of the components have been removed in the area
of the wiring. Could definitely make a difference in the audio operation!

I have the layout/schematic for a HLN6074A, which appears to be
slightly different than the board you have, but it oughta be pretty
close.

If you can take a better pix (straight down), it might help see what
parts aren't there.

Unsolder the wires carefully & check around for shorts & cuts on the PCB.
He may have cut some traces.

Keep us posted!

Tim
Tim
 
Posts: 448
Joined: Wed Mar 20, 2002 4:00 pm

Re: Weird Spectra wiring

Postby fchrist16 » Tue May 18, 2010 10:57 am

Here is another image of it.
Image


If I could get that schematic to figure out what might be wrong that would be great. Meanwhile I'll try and get the wires off carefully...

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby GlennD » Tue May 18, 2010 11:12 am

If you have access to spectra lab, I will send you a command board for $10 shipping and handling.
THAT IS REALLY UGLY. IF I DID THAT I WOULD HAVE TO RESIGN AS A TECH!
GlennD
 
Posts: 410
Joined: Tue Jun 15, 2004 8:00 am
Location: Anaheim (retired Long Beach)

Re: Weird Spectra wiring

Postby fchrist16 » Tue May 18, 2010 11:15 am

Glenn,

Thanks for the offer but as I'm strapped on cash I can't get a new command board yet so I was hoping to easily fix this. I was able to take off the wires with minimal effort...Beyond there I'm not sure what to do without a schematic or other instructions...


Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby Tim » Tue May 18, 2010 11:18 am

Hi Frank,

Looking from left to right, the most left capacitor is a tantalum.
Then next one right (missing) should be a 0.01uF (C419) . It is in the RX
in line - no audio without it.

The other part that is missing is C409 - 0.0039uF. This is in the
mic audio in line - probably doesn't talk either.

Drop me a note at tahrens at swtexas dot com, and I'll send you
a copy of the schematic that I have. It is a HLN 6094, although I also
have the schematic for a HLN6074A

Tim
Tim
 
Posts: 448
Joined: Wed Mar 20, 2002 4:00 pm

Re: Weird Spectra wiring

Postby com501 » Tue May 18, 2010 11:35 am

Someone installed a TransCrypt rolling code voice inversion scrambler.

Look on their website, they should have the modifcation notes which will allow you to reverse engineer this.

If you call them if it is not on their website they can definitely get you what you need.
com501
 
Posts: 883
Joined: Fri Nov 02, 2001 4:00 pm
Location: Nevada Test Site
What radios do you own?: Over 50 - All Motorola

Re: Weird Spectra wiring

Postby Will » Tue May 18, 2010 11:55 am

What a BUTCHER JOB......

One of the worst I have seen in 20 years...
Will
 
Posts: 6668
Joined: Tue Sep 04, 2001 4:00 pm

Re: Weird Spectra wiring

Postby fchrist16 » Tue May 18, 2010 12:00 pm

Will it came to me like this...How are my other radios going??

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby jackhackett » Tue May 18, 2010 2:50 pm

did they leave the leads on the caps long enough?

The encryption board wires actually don't look that bad... from what I can see if you unsolder them carefully the component pads should be okay and you can just solder in new chip caps. I've seen worse, with traces all hacked up and stuff.

Are there any other signs of modification? I'm not familiar with those particular modules, but typically an encryption module would have connections for rx and tx audio (the yel/org & blu/grn wires), power (the red.. should also be a ground somewhere) and some method of switching on and off, which could be a toggle switch added somewhere (is there a hole in the radio?), or some way of controlling it with one of the radio's buttons, which could mean another circuit mod somewhere such as the control head. They may have even connected an external switch through the accessory plug somehow, or... if you're lucky, they just ran encrypted full time so no switch was needed.
User avatar
jackhackett
 
Posts: 1188
Joined: Tue Jun 10, 2003 8:52 am
Location: Nuns! Reverse!!!

Re: Weird Spectra wiring

Postby fchrist16 » Tue May 18, 2010 2:58 pm

There was a toggle switch on the control head. I didn't think of using that head with this radio as I had re-programmed it for another head. I don't easily see any other mods to this radio besides those wires, which I have taken off and replaced with the help of the local electronics store and their soldering iron/magnifying glasses.

EDIT: Now it's worse than before. I went and put the right control head on and now I'm stuck in the "self check" boot...
REEDIT: Forgot the MLM Board. Now the "self check" boot is gone but the audio issues remain...

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby jackhackett » Tue May 18, 2010 4:14 pm

If it had a toggle I think you should be okay just replacing the two missing caps, basically what they do is insert the encryption circuit into the transmit and receive audio signal paths, and the easiest way to do that is take out some coupling caps... put the caps back in and you should have audio again. I suppose your biggest problem would be finding the caps...
User avatar
jackhackett
 
Posts: 1188
Joined: Tue Jun 10, 2003 8:52 am
Location: Nuns! Reverse!!!

Re: Weird Spectra wiring

Postby fchrist16 » Tue May 18, 2010 4:18 pm

Finding the caps and replacing them wasn't that hard...The only issue is the caps are half soldered down and half superglued down...The audio remains the same as before so something else must be going on??

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby jackhackett » Tue May 18, 2010 4:36 pm

Superglue? oh..... not a good idea... that stuff gives off some really nasty fumes if you get it too hot.. I've gotten the smoke from it in my eye a couple of times.. feels like having a hot needle stuck in your eye.

That aside, if the solder joints on the caps are good, there must be something else going on, not sure what it could be.

For soldering in chip components you can put a small amount of solder on one pad, then put the component on and use something like a toothpick to hold it still while you reflow that side, that will hold it so you can solder the other side, finally go back and flow a little fresh solder on the first side to make sure it's got a good joint.
User avatar
jackhackett
 
Posts: 1188
Joined: Tue Jun 10, 2003 8:52 am
Location: Nuns! Reverse!!!

Re: Weird Spectra wiring

Postby fchrist16 » Tue May 18, 2010 4:40 pm

Oh I did the superglue after the soldering of the other side! All solder points are good. The radio boots up and checks out fine otherwise it seems. Just this one little issue.

Anyone else have any ideas or do I mark this one up to a "bad buy" and move on? I really don't want to have to do that either...

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby n4bfd » Wed May 19, 2010 2:51 pm

I have the exact same problem with a Spectra I just started up today for the first time, and it's my first Moto.
I have very low receive audio, I have to put it all the way up to hear anything, but the "beeps" from the key on the head will blast you out at that level. No TX.
Control head has a toggle switch. Initally when I saw that I thought it may have been a on off since the control head was mounted flush in a console, as it came with the console plate still on it.
I got this from a guy who is selling them on 2 ham boards and on ebay. I've not contacted him yet, as I just found this in the last hour and wanted to see what you guys think.

In the third photo there seems to be a bundle of wires that are in a hole in the middle of the pic, that are cut flush with the board, is this normal?

Image
Image
Image
n4bfd
New User
 
Posts: 2
Joined: Sat May 15, 2010 10:07 pm

Re: Weird Spectra wiring

Postby fchrist16 » Wed May 19, 2010 4:13 pm

Alright so I was thinking and reading and didn't think "Oh wait my 45w VHF Spectras have the same Command Boards". Well I went pulling and found a good one and now my radio works as needed. So now I have to figure out what else was wrong with that command board.

Thanks again for everyone's help here! Batlabs is the place to be!

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby fchrist16 » Thu May 20, 2010 11:11 am

n4bfd wrote:I have the exact same problem with a Spectra I just started up today for the first time, and it's my first Moto.
I have very low receive audio, I have to put it all the way up to hear anything, but the "beeps" from the key on the head will blast you out at that level. No TX.



n4bfd,

That was exactly like mine...May I ask without upsetting the batlab gods, where did yours come from? There maybe a pattern.

If you want you can PM me with the reply.

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby Bill_G » Thu May 20, 2010 11:20 am

I would say that confirms an agency was using Transcrypt (or similar) boards, took them out of service, sold them by the lot, and you guys are the lucky recipients of the single sales. Caveat emptor. At least it looks reversible.
User avatar
Bill_G
 
Posts: 2520
Joined: Thu Sep 17, 2009 5:00 am
Location: Portland, OR

Re: Weird Spectra wiring

Postby fchrist16 » Thu May 20, 2010 11:26 am

Bill_G wrote:I would say that confirms an agency was using Transcrypt (or similar) boards, took them out of service, sold them by the lot, and you guys are the lucky recipients of the single sales. Caveat emptor. At least it looks reversible.


Agreed. I think later today I'm going to take my head apart and examine it...

Regards,

-Frank C.
fchrist16
 
Posts: 217
Joined: Sun May 24, 2009 12:23 am
What radios do you own?: Spectra's, Jedi's & more

Re: Weird Spectra wiring

Postby n4bfd » Thu May 20, 2010 11:53 am

I'll PM you where I got it from. To the sellers credit, I fired off a email about it last night, and he responded very quickly, and is sending me another that he has tested. The seller has been selling them for awhile on couple of boards and ebay, so I think if they were all like this something would have come out about it now.

fchrist16 wrote:n4bfd,

That was exactly like mine...May I ask without upsetting the batlab gods, where did yours come from? There maybe a pattern.

If you want you can PM me with the reply.

Regards,

-Frank C.
n4bfd
New User
 
Posts: 2
Joined: Sat May 15, 2010 10:07 pm


Return to General Motorola Radio Discussion

Who is online

Users browsing this forum: Google [Bot] and 3 guests