UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Op-Amp RIAA Preamp with Tone Controls

cathoderay57 · 25th Sep 2020, 10:22 pm

They are cheapo jacks mounted on a small plastic panel so isolating them is easy. Also Craig's point is very pertinent - I just put the scope on the PSU rails and there is unacceptable ripple so that definitely won't be helping things. I've just ordered LM7815 & LM7915 regulators. I'm still not sure why the hum is worse on one NE5534 than the other - maybe just differences in layout and proximity of power and signal rails.

25th Sep 2020, 10:22 pm	#23
cathoderay57 Nonode Join Date: Oct 2017 Location: Bristol, UK. Posts: 2,388	Re: Op-Amp RIAA Preamp with Tone Controls - Help! They are cheapo jacks mounted on a small plastic panel so isolating them is easy. Also Craig's point is very pertinent - I just put the scope on the PSU rails and there is unacceptable ripple so that definitely won't be helping things. I've just ordered LM7815 & LM7915 regulators. I'm still not sure why the hum is worse on one NE5534 than the other - maybe just differences in layout and proximity of power and signal rails.