Re: Bush TR106GL
Hi folks, well, I’m embarrassed to say I’m stuck on this one and could do with pointing in the right direction. The radio ‘works’ but the agc doesn’t seem to be doing its job properly. When a station is tuned in I get clipping like distortion on the audio and a scope on the collector of VT3 shows a clipped IF waveform of about 7volts p-p (full supply voltage) . Tune to one side of the carrier and the IF amplitude reduces and I get un-distorted audio. All the transistor voltages are about right (within 0.2 volt). C8 and C9 are both fine, I did find R5 was high at 140k but changing that made no difference. There is about a 1.5 volt change on C9, the agc smoothing capacitor and R10 is about right. Any advice welcome. Dave
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