Author Topic: RCA RP230 (1968-9) feather-ride cartridge #115277  (Read 1348 times)

Motorola Minion

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RCA RP230 (1968-9) feather-ride cartridge #115277
« on: April 18, 2019, 10:21:34 AM »
Many RCA's I see like this still seem to sound OK with a new stylus but I have run into two that, after some gentle cleaning and re-lube, operate fine mechanically but sound awful.

After installing a new Pfanstiehl 648 stylus, sound still cuts in an out like truly bad stylus. .

I recapped the SS amplifier and the radio/aux input sounds great. On the phono, sound is equally weak on both channels, actually sounds like you're in a tunnel.

Any bump or movement of the tone-arm makes noise, making me think the compliance has hardened from age.

The attached shows a kit from V-M music enthusiasts, which I will need to consider if I cant find a good NOS cart.
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Dave

TC Chris

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Re: RCA RP230 (1968-9) feather-ride cartridge #115277
« Reply #1 on: April 18, 2019, 07:13:59 PM »
The cutting-in-and-out isn't a stylus issue, it's a cartridge issue.  Ceramic and crystal cartridges operate by flexing a crystal or ceramic piezoelectric element to generate a small voltage.  When the piezoelectric element fails, or the connections to it fail, then it won't generate reliably and sound will be interrupted.  The stylus just rides in the groove and causes the element to flex.

Chris Campbell

Motorola Minion

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Re: RCA RP230 (1968-9) feather-ride cartridge #115277
« Reply #2 on: April 19, 2019, 12:11:52 PM »
The construction of ceramic cartridges seems overly-simple, dried-up compliance deadens many, but not all vibrations, the stylus is supposed to transmit to the ceramic elements to which the signal wires are somehow connected. I never did understand that last part.

If I find a good one, it may pay to make duplicates of that compliance if possible with a 3D printer to rebuild it.... ::) or so you would think.

I just repaired THIS changer in a small console for someone and indicated I may need to do a tone-arm transplant once I find a suitable solution.

The sad part about these OEM cartridges dying is that all those replacement styli still for sale, are not much help.
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Dave