The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

All of a sudden I have perfect TX in all bands and modes,but RX I have no RX and the RX meter is all bars like someone is giving it a dead key.And also the Clarifier when you turn it it changes Frequencys you can go from 27.185 to 27.835 the radios feq counter doesnt change but the external one changes and its transmits were its reading but same problem no matter what band or channel no RX.I have changed the two 8volt regulators and main regulator and Battery.Any help would be great hate to scrap this radio.

hey there,,,sounds like it is stuck in transmit mode..if so you have a shorted switching diode..............................ramblingman

you still have to key up the mic to TX and the display says RX,could it still be a keying Diode?

It sounds like the MPU has gone south, check the MPU data stream from main PCB to the CPU/MPU, digital scope req or storage scope. This is a common fault I have had to scrap a few due to this problem.
Check out my diagrams and info on the likes below, it may help.

http://www.cbtricks.com/radios/rci/rci_ ... 0z_sch.pdf

http://www.cbtricks.com/radios/rci/rci_ ... _notes.pdf

http://www.cbtricks.com/radios/rci/rci_ ... 50_sch.pdf

Ok thanks Rick will check it out.That really sucks if that is what went out this radio is in mint shape.Thanks again for the help and time you and others have took to help me out.