Hi folks! Glad to be here. I have a 1967 RCA console stereo equipped with a studio strobe changer turntable. It’s an older wheel drive and is equipped with an Astatic 355 ceramic cart. Everything sounds amazing, except a low hum only when the motor is running and the stylus is on the record. Pretty sure I’ve been able to rule out an electrical issue - under power if I place the stylus on the record but don’t engage the motor, very quiet, but as soon as the idler wheel touches the platter - hum. I’ve heard that when the older wheels get old and hard that they can cause resonance in the platter, and can cause a hum. It’s not bad, just annoying and I’d love to fix it - I’m thinking of getting some rubber renue to see if that helps. Any suggestions? Thx!
Sounds like rumble Does the deck float? Sometimes the transit screws have to be released to ensure this. A good clean is a start
Do all moving idler wheels move freely? The e-clips may need to be removed, wheels removed, cleaned with alcohol and then re-lube with oil. The motor may also need a clean and lube too. Old grease can turn 'gunky' and harden over time.
"Hum" to me means an electrical hum. Is it an electrical hum or a mechanical hum or rumble? You say it happens when the motor is engaged - is the turntable in "N" or other freewheeling setting? Is there a (mechanical switch) cutoff for the audio when it is in "N' or other? Put two junk records on the turntable, set the needle on the top (of course) one as if to play it, and engage the motor while holding the top record still, sliding on the bottom record which is spinning. Do you get an electrical or a mechanical hum doing this? Ceramic carts do go bad in time, and 50 years is about time. And all kinds of things can go wrong from old age in a 1967 console.
If it's an electrical hum, well! that's a different story! Grounding, bad cartridge, filter caps need replacing....
Thanks for all of the Responses! I’m going to look at all of these, I got this from my grandmother - so I’m the second owner - but wow can things get dirty over 50 years haha I do think I’m looking at a rumble issue, it’s just has a low volume higher pitched “hum” noise that you hear when stylus touches record while spinning - off to trouble shoot!