Need schematic or part info

alorotom · Post by **alorotom** » Mon Mar 04, 2002 6:19 pm

I have a Motorola Radius M120. The company that I work for attempted to destroy it by cutting all the wires and cables. They had purchased new equipment. On the board that is mounted in the heat sink, they damaged a resistor that is mounted above the Motorola trademark and date that is printed on the board. Does anyone have any specs. on this part? Can it be purchased at an electrinics supply dealer or from Radio Shack? My plans are to have this transceiver reprogrammed for GMRS which I'm licensed for.

Thank You
Paul
WPSR954
KC8DDQ
[email protected]

Will · Post by **Will** » Tue Mar 05, 2002 1:22 am

You may be reffering to the transmitter current sensing resistor. It is usally a .02 ohm resistor and most RS do not have anything that low. Did it get destroyed physically?

alorotom · Post by **alorotom** » Tue Mar 05, 2002 10:29 am

On 2002-03-05 04:22, Will wrote:
You may be reffering to the transmitter current sensing resistor. It is usally a .02 ohm resistor and most RS do not have anything that low. Did it get destroyed physically?

It is completely gone. Everything else around it is untouched. I have a .05 ohm K that I got off a junked M120 but it is physically smaller. I can add length to the leads if it will work. Would the .03 difference make that much of a difference?

Thanks
Paul

Will · Post by **Will** » Tue Mar 05, 2002 3:14 pm

The resister needs to be the same as the original one so the power control circuits for the transmitter will work correctly.
I think I will take a look at one to see what the value is on it.

alorotom · Post by **alorotom** » Tue Mar 05, 2002 6:26 pm

On 2002-03-05 18:14, Will wrote:
The resister needs to be the same as the original one so the power control circuits for the transmitter will work correctly.
I think I will take a look at one to see what the value is on it.

I appreciate your help Will. Here is some other info that might be of help....

Serial # : 799TUU4682
Model : M04GMC20A3AA
Tanapa : HUE3016A
FCC : ABZ99FT4033
Doc/Mdc : 10919310331
Type : GMUA

This is info that is on the heat sink. Figured it might tell you year of manufacture or a certain production run. I know that manufacturers sometimes inplement design changes in the middle of a run.

Thanks
Paul

Mike B · Post by **Mike B** » Tue Mar 05, 2002 6:55 pm

According to my M120 service manual part number 6880902Z98 ($ 11.50 retail):

Your radio is a 20/25 KHz split UHF 438-470 MHz 1 to 10 watts.

HL8267A UHF 1-10 watt PA deck; R2570 is a FMO resistor, 0.2 ohms, 2 watts, part number 06-11086D01 (10/pk) $ 2.10 retail from Motorola. For a part like this one, I would recommend the Motorola part, not a Rat Shack or over the counter substitution.

Sorry the service manual board layout drawings do not show the Motorola trademark or date code, so I will have to assume the others identified the correct resistor that needs replacing. I only have the manual to look at.

BTW, different power range PA decks use different resistors. The UHF 10-25 watt PA deck uses a .05 ohm resistor with an entirely different part number. I do not think your resistor from the junked M120 is the correct part. The higher power decks use a .01 ohm resistor with yet another part number.

[ This Message was edited by: Mike B on 2002-03-06 00:12 ]

alorotom · Post by **alorotom** » Tue Mar 05, 2002 7:27 pm

Mike,
There is a number printed on the board in the heat sink (PA Board)? It is HLE3370A. There are some more numbers...

ISS A
84D80403C02
9444 MAL

Hope this helps.

Paul

Mike B · Post by **Mike B** » Tue Mar 05, 2002 7:55 pm

There is a HLE3770A listed in the manual. The manual may have a typo or maybe you got the part number wrong? This part number is a combination kit part number consisting of a HLE8267A PA board and HLN8268A PA hardware.
________
Mike B
[email protected]

[ This Message was edited by: Mike B on 2002-03-06 00:14 ]

Will · Post by **Will** » Tue Mar 05, 2002 8:06 pm

Your M120 should be fine on the regular GMRS 25 khz frequencies. And the resistor details are correct per my infomation. Always use the Moto part here.You can tell the LPI version in that it only has one "winged transistor" the one with four tabs that mounts with a nut from the back of the heat sink. Higher power radios, UHF 25 and 45 watt have the four winged transistor plus another transistor that mounts with two torx screws and has six tabs soldered to the board.

alorotom · Post by **alorotom** » Tue Mar 05, 2002 9:06 pm

On 2002-03-05 23:06, Will wrote:
Your M120 should be fine on the regular GMRS 25 khz frequencies. And the resistor details are correct per my infomation. Always use the Moto part here.You can tell the LPI version in that it only has one "winged transistor" the one with four tabs that mounts with a nut from the back of the heat sink. Higher power radios, UHF 25 and 45 watt have the four winged transistor plus another transistor that mounts with two torx screws and has six tabs soldered to the board.

Thanks for the info guys. So it looks like I need a .2 ohm 2 watt resistor Mot. part # 06-11086D01? Will you are correct on the transistor layout.

Thanks
Paul

Mike B · Post by **Mike B** » Tue Mar 05, 2002 9:18 pm

Will,

Thank you for correcting my bad assumption. I had assumed that the FCC had re-farmed GMRS as 12.5 KHz. I corrected my previous posts.

Alorotom,

Yes, that is the part number from the manual (I just triple checked it). For what you are attempting to do (i.e. putting a chopped radio back together), I would strongly recommend you get a manual as well. Is it only $ 11.50 retail and it can come in very handy (part number 6880902Z98).
_______
Mike B
[email protected]

[ This Message was edited by: Mike B on 2002-03-06 00:29 ]