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1963 RCA 4VC51 record player tone arm help!
Posted: Wed Apr 09, 2008 7:28 am
by TT52103
I have a 1963 RCA record player model # 4VC51 and I need help adjusting the tone arm. There doesn't seem to be a screw in there to adjust the height of it. The problem is it seems to be too heavy for the needle. When I play a record I only get sound out of one speaker. But if I lift up the arm slightly with my finger while a record is playing...I then get sound out of both speakers.
Can anyone help with this?

Re: 1963 RCA 4VC51 record player tone arm help!
Posted: Thu Apr 10, 2008 6:03 pm
by Record-changer
The height and the stylus force are two different things.
The stylus force is controlled by a spring inside the arm. To make the force lower, increase the spring tension. On most RCA arms, this is done by moving a clip under the center of the arm. But don't guess. Find out the proper force, and use a force gage. (Most RCA units in the 1960s used a force of from 4 to 6 grams-equivalent.)
The arm height is the height the arm rises during a change cycle. It is adjusted to give enough clearance for the stack on the turntable, but without hitting the stack on the spindle.
You may have a bad cartridge or cartridge wiring. Ceramic cartridges die from exposure to humidity over time. Or the stylus cantilever might not be centered in the saddle.
Re: 1963 RCA 4VC51 record player tone arm help!
Posted: Mon Apr 14, 2008 6:00 pm
by MattTech
Sorry, you're wrong.
Crystal cartridges, NOT Ceramic ones, go bad over time.
The Rochelle crystal deteriorates from age and humidity. Ceramic is immune to this.
Re: 1963 RCA 4VC51 record player tone arm help!
Posted: Wed Apr 16, 2008 3:52 am
by Record-changer
If ceramic cartridges are immune to this, then how come I am seeing so many bad ones in stored units?
Posted: Tue Apr 29, 2008 7:27 am
by MattTech
Ceramic elements are brittle, just like rochelle salt crystal.
But the main reasons for malfunctioning in ceramic cartridges is abuse, hardening of the rubber yoke/suspensions, and even corrosion of the electrical contact surfaces due to mildew from damp basements. Age takes it's toll on most anything.
As for the OP's problem of channel loss, they need to make sure the stylus pressure is within spec, and the spring is not missing. RCA tonearms from the 60s have a non-adjustable spring arrangement set for 5-7 grams, or a floating cartridge,(a.k.a. "FeatherTouch" sometimes designated by a feather on the arm) also non-adjustable.
Re: 1963 RCA 4VC51 record player tone arm help!
Posted: Sat Mar 07, 2009 5:36 am
by stereoplayers
I have always wondered why RCA Victor, "The Most Trusted Name In Electronics," had a high(er) tracking weight on their tonearms during the 1960's, without any real tracking adjustment (seems like it defeats the purpose). I have an RCA Victor model VLJ-41-W console (had to change the changer out of it since the other went bad; exchanged it with one from close to the same period), shortened the tonearm spring a small fraction, and to help alleviate the wear on the "dust-collecting" tracking pad, placed a very small piece of foam between the cartridge and under-side of the headshell. Works just fine...
Re: 1963 RCA 4VC51 record player tone arm help!
Posted: Thu Mar 19, 2009 7:44 pm
by Record-changer
The tracking force was higher because RCA used plain sleeve bearings in its tonearms. Ball or cone bearings are needed for low tracking forces.
The tracking force is adjustable, by bending the spring holder on the pivot bracket. I was thinking of the one RCA I had that came with a V-M changer.
Re: 1963 RCA 4VC51 record player tone arm help!
Posted: Fri Mar 20, 2009 2:50 am
by MattTech
The spring/force isn't "adjustable" by bending the springholder, because on the RCA "Studiomatic" RP217/218's that this thread is about, and in consoles from 1962-1964, are made from pot-metal and will snap right off.
Diagram:

- RCA Studiomatic Arm RP-217-218 series
- rca-arm.jpg (45.04 KiB) Viewed 3781 times
Re: 1963 RCA 4VC51 record player tone arm help!
Posted: Tue Mar 24, 2009 4:04 am
by Record-changer
I was thinking the RP-215.