Hi, I have a 29, I was talking on it the other day and it lost Receive, it transmits and modulates great, PA works great! no meter movement on rec, no sound. what could be the problem,? someone told me to replace r 31 so I did, no help! the schematic showed a 47K ohm there, but it originally had a 4.7K ohm there? please ? thanks for any info, I am a disabled vet with limited income, and try to repair all my junk..