Saber Receive question

Jim70563 · Post by **Jim70563** » Thu Feb 28, 2002 11:51 am

I have a Saber I 136-151 split. It transmits fine, but deos not receive. Programming is correct, and it has a receiver in it from another portable that I know works. (Swapped them just to see if it was a receiver prob).

If the receiver is fine, what else could be keping it from receiving??

All Freqs programmed are within the specs.

Any help would be appreciated. Hopefully it is just a module that needs to be swapped out...

Jim

cracked · Post by **cracked** » Thu Feb 28, 2002 2:38 pm

do you have any noise from the speaker when you press the monitor button?

Jim70563 · Post by **Jim70563** » Fri Mar 01, 2002 11:23 am

Yes, I hear static when the monitor button is pushed. It boggles my mind. I have two of these radios, one digit apart on serial numbers. I swapped the Receiver from the one that works to the one that doesn't. Both receivers work on the radio that has no problems.

[ This Message was edited by: Jim70563 on 2002-03-01 14:24 ]

RadioSouth · Post by **RadioSouth** » Fri Mar 01, 2002 11:40 am

Are these securenet capable radios ? If so
make sure you have a bypass or secure module
installed otherwise audio would not pass thru radio as your describing.

Jim70563 · Post by **Jim70563** » Fri Mar 01, 2002 11:44 am

These are securenet capable and have the DES modules installed...let me check that next..with a swap out!

OK, Tried the swap out of DES modules. No change. The DES from the bum radio works fine in the good radio. The DES from the good radio does not help the bad radio. Back to square one. Thanks for the idea though!

[ This Message was edited by: Jim70563 on 2002-03-01 14:57 ]

[ This Message was edited by: Jim70563 on 2002-03-01 14:58 ]

[ This Message was edited by: Jim70563 on 2002-03-01 14:58 ]

cracked · Post by **cracked** » Fri Mar 01, 2002 12:06 pm

the module you tried swapping was the filter/amp/mixer module (between the ref osc xtal and FDS module)? checked all modules for broken pins? squeezed/tapped/etc radio with input signal to see if problem is intermittent? TX power out OK (if not, suspect bad antenna or bad antenna connection)? if all of the above is OK, i'll bet on a bad FDS module. i think this does some sort of RX/TX switching. try swapping that out with your good radio.

N4UMJ · Post by **N4UMJ** » Fri Mar 01, 2002 12:23 pm

I had a unique problem that may or may not relate to what you are experiencing.

The antenna connection to main pc connection was bent back on one of my Sabers. A check with an ohmeter from the threaded antenna connector to the PC board showed several ohms. Bending this back made it somewhat better but only until I cleaned both contacts with a contact cleaner did the resistance drop to what it should be.

Not too sure what kind of strange effects this high resistance connection would have caused because I just happen to be curious and confirm things as I was reassembling a Saber that I had taken apart all the way down to the frame level.

Something to keep in mind.....

Good Luck!

Eddie
N4UMJ

Jim70563 · Post by **Jim70563** » Fri Mar 01, 2002 1:28 pm

Well...I just spent two hours swapping out every module that could be removed between the two radios. Still no receive on the bad radio. The good radio worked fine with the swapped parts. I guess the next step is the Motorola Shop...Thank you all for your suggestions!

Elroy Jetson · Post by **Elroy Jetson** » Fri Mar 01, 2002 6:30 pm

I'm wondering if it's working, but on the wrong frequency. Do you have any way of finding out?

Your reference oscillator may be bad, if so, or the warp adjustment (in software) may need to be tweaked.

If it's not that, then in all likelihood you have a defective chip on the PC board, and that's a trip to the shop for most people.

Elroy