Needing Schematic: Rebel TX500 (Mongoose 450) CB radio

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wcsd106
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Posts: 1
Joined: Monday 7th Dec 2009, 15:31
First Name: Josh
Location: USA

Needing Schematic: Rebel TX500 (Mongoose 450) CB radio

Post by wcsd106 »

Radio Make and Model: Rebel TX500 (Silver faced clone of Mongoose 450)
PCB Number: jpmxx0222-a
PLL Number: MC145106
Test gear available: Most test gear available (Currently without oscilloscope as I sold mine a few years ago when I considered getting out of this business and haven't purchased a replacement yet.)

Symptoms: Radio shows no transmit wattage. Radio can be heard slightly on a nearby radio, but no output power is observed. Checking transistor voltages against an identical working model, Q18 (RF Amp) does not jump to +12v on tx. Stays at 9v regardless of key condition. No voltage chart or schematic available to aid in troubleshooting this unit.

What is working: Receiver working 100%, audio section seems to be working.

What has been tried: Final & driver have been replaced with known working components (acted like final at beginning)

Did it suddenly happen ?: Radio was purchased in non-working condition from Ebay
Anything else that may be of help?: have identical radio (Mongoose 450) in 100% working condition. I have been using it as a 'control' radio to observe voltages for reference. Also, according to an info sheet I read on the Mongoose, when troubleshooting transmitter problems it said to check for a faulty D15. I cannot locate Diode D15 on this chassis.

If anyone has a service manual or schematic on this radio, or could point me in the right direction to obtain one, it would be greatly appreciated.

Thanks.
Kosmic
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Posts: 6
Joined: Monday 29th Sep 2008, 9:48
Location: Florida

Re: Needing Schematic: Rebel TX500 (Mongoose 450) CB radio

Post by Kosmic »

Josh they are very sdimilar to a Tristar 240 as far a circut. Hopefully this helps.
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