UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - 6-gang FM stereo tuner heads

G0HZU_JMR · 27th Nov 2022, 5:18 pm

Probably a good place to start would be with your signal source(s). It might be better to make something cleaner for f1 and f2.

Maybe make a couple of 5th overtone crystal oscillators to get you up to 100MHz. Then filter and buffer each with a high reverse isolation amplifier and then combine in a classic 6dB combiner.

Otherwise, it's hard to comment on your analyser plots. Hopefully, the numerous spurs are due to your current signal source and combiner setup and not from something inside the analyser.

Whoops, I just saw that we double posted. You already tried a cleaner source.

27th Nov 2022, 5:18 pm	#293
G0HZU_JMR Dekatron Join Date: Sep 2010 Location: Cheltenham, Gloucestershire, UK. Posts: 3,077	Re: 6-gang FM stereo tuner heads Probably a good place to start would be with your signal source(s). It might be better to make something cleaner for f1 and f2. Maybe make a couple of 5th overtone crystal oscillators to get you up to 100MHz. Then filter and buffer each with a high reverse isolation amplifier and then combine in a classic 6dB combiner. Otherwise, it's hard to comment on your analyser plots. Hopefully, the numerous spurs are due to your current signal source and combiner setup and not from something inside the analyser. Whoops, I just saw that we double posted. You already tried a cleaner source. __________________ Regards, Jeremy G0HZU