I found a Phase Linear 5000 FM tuner on Ebay for $46 plus shipping. The seller had stated that the stereo light wouldn't
lock on to stations and the 19 kHz pilot tone needed repair. I guess this is why nobody else bid this unit up.
My Electronic Guru brother in law attached a frequency counter to the demodulation circuit and sure enough the
19 kHz tone was over 22 kHz. He examined the trim pot and it seemed within specifications but would not adjust below 22 kHz.
Before replacing the LM1800 demodulation IC he decided to remove the 390 pf capacitor in the circuit and although it measured to specs he replaced it and BAM a perfect 19 kHz tone and stereo light comes on like a laser. (Must have been cold solder joint)
I had to replace the on/off switch as the previous owner had done a bad job on the previous replacement.
The lamp dial reflector was rusted so I sanded it down and repainted it silver. (Rust doesn't reflect light very well)
Sanded and refinished the chassis cover and replaced the original RCA outputs with CMC RCA outputs. (bling is my middle name)
Changed the lamps to bright white led's and they really bring out the silver of the dial.
Now I have a very minty tuner that works perfect.
Now to find a wood cabinet.
lock on to stations and the 19 kHz pilot tone needed repair. I guess this is why nobody else bid this unit up.
My Electronic Guru brother in law attached a frequency counter to the demodulation circuit and sure enough the
19 kHz tone was over 22 kHz. He examined the trim pot and it seemed within specifications but would not adjust below 22 kHz.
Before replacing the LM1800 demodulation IC he decided to remove the 390 pf capacitor in the circuit and although it measured to specs he replaced it and BAM a perfect 19 kHz tone and stereo light comes on like a laser. (Must have been cold solder joint)
I had to replace the on/off switch as the previous owner had done a bad job on the previous replacement.
The lamp dial reflector was rusted so I sanded it down and repainted it silver. (Rust doesn't reflect light very well)
Sanded and refinished the chassis cover and replaced the original RCA outputs with CMC RCA outputs. (bling is my middle name)
Changed the lamps to bright white led's and they really bring out the silver of the dial.
Now I have a very minty tuner that works perfect.
Now to find a wood cabinet.
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