Technics SL-1210mk2 Tonearm Feedback

[bar72]

Just picked up a NOS Technics SL-1210mk2. Never been used. Fitted an Ortofon SH-4 Heashell with an AT95e cart that was lying around to get it up and running but when it's powered up, with no vinyl spinning and I tap the armwand or use the armwand lock, I can hear feedback through the speakers. Also if I tap the plinth, same as. If I tap the shelf where the feet are resting on, no feedback.

01/ Can I assume that it's just a poorly insulated tonearm on these models?

02/ I've just retired an SL-120mk1 with a Rega RB300 arm, can I transplant the Armboard from a mk1 to a mk2?

 

[cafe latte]

Do you have good ground for the turntable? Also had an odd issue recently with a headshell with anodising which insulted it from the arm wet and dry 600 grit fixed the problem with that headhsell. Technics arms dont hum there has to be an earth problem or loop or the cart needs to be insulted from the headshell which some do or there will be hum ie plastic washers and screws.
Chris

 

[bar72]

Just checked with an old Ortofon Concorde DJ Cartridge and hum gone. The Ortofon Brand New..

edit:

If I remove AT95 stylus from cartridge body, everything silent. When I reseat stylus, feeback is back. Is this a knackered stylus?

edit:

All good with another AT Cart.

AT95 must been DOA

 

[tnsilver]

I was about to say it's the way it is, perfectly normal and just don't tap it - then you used the word 'hum'. It's a different thing than 'feedback'...