Rabco Sl8e

6 years ago, i stopped playing my vinyls. principally as he result of rearranging my gear space so as to accommodate some cd gear. the turntable that i took out of service was one that i bought used[virtually new] from a fellow marine who had acquired it in japan, so he said. it carries no sony part number. it carries a faceplace that identifies it as a servo turntable system. elsewhere, it is identified as a servo-controlled turntable. i believe it to be of a direct-drive design as it provides for speed fine-tuning.

when i acquired it, it was outfitted with a SME arm. apparently as the original equipment selected by sony. eventually the arm had to be replaced. i replaced it with the RABCO.

i considered this a fabulous combination of components for playing vinyl.

within the last few weeks, in the process of auditioning a replacement for my nakamichi cd2 player, i found a shop in austin, whetstone audio, that offered me the chance to compare/contrast vinyl to digital.

i grabbed a yupiteru lp of art pepperr, i took the japanese cd version, i took my tascam dupe of the cd.

first we played the lp on a rega p3 with a dynavector 10x4 cartridge. made me want to start playing my vinyls again. especially since i have some vinyls that have never been commercially duped to cd, which i could now record to cd on hhb cdr850.

so, this weekend, i rearranged my gear room so as to return that sony and the rabco to service. the turntable spins, but the rabco mechanism fails to pull the arm, so after a deflection similar to what would be encountered in the run-out area of the lp, the arm lifts.

i am not surprised by this as an infrequently-used mechanical device often forgets how it is supposed to work. but for the few minutes that it plays, it is sonically the equal of the rega p3 and dynavector.

but this rabco is 30 years old, now. it is little known.

anyone out there know of a techie that is familiar with rabco arms that could administer cpr to this one?

all ears.

I have rebuilt one of these. Unfortunately, you have to take a lot apart to get it working. Let me explain how it works. When the record plays, the record groove pulls the front of the tonearm to the left. There are two sets of contacts in the arm, they make two circuits that drive different motors in the arm. As the arm moves to the left slowly, the first contact is made. This closes the circuit that turns on the side motion motor. There is a ball type chain that pulls the tonearm to the left as the motor runs. This keeps the arm straight, every time it gets a bit crooked, the motor runs and straightens it out, so it stays square to the groove. In the inside of the tonearm, there is a spot where there is a small piece of foam rubber. When the tonearm lift motor lets the arm down, the tonearm carrier pinches the ball chain against the foam rubber so that the tonearm moves along with the chain.
At the end of the record, the run out groove moves the arm to the left much faster, and the side motion motor is slow, it cannot keep up. So then the arm moves far enough to the left, so that the second set of contacts is made, that starts the lift motor and lifts the arm. When the tonearm lifts, the chain is no longer pinched against the foam rubber, so that it can slide side to side freely.
The most common problem is with the foam rubber. When the rubber gets old, it wears, and gets hard, so that the tonearm no longer grips to the chain, and no longer moves. Then the tonearm moves farther to the left than it would in normal operation, and when the second set of contacts if made it lifts. The solution is to replace that little piece of foam rubber.
The second problem that could occur is that the contacts might not be making good contact. The contacts look like crossed sewing needles. Some deoxit might help. But don't fool with the contacts until you have ruled out all other causes, they are kind of fragile.

I always fancied one of the Rabco arms to play with but the closest I got was an Audiomeca SL5 which needed constant attention to keep on song :scratch2:

I don't know if you've seen Rudolf Bruil's Rabco page? It has some useful info and he will even do you a copy of the service manual/troubleshooting guide if you end up needing one:

http://www.xs4all.nl/~rabruil/ttrabco.html

so serendipitous. as i read the date on the bruil essay, it was put up on sunday.

i shall take all the help that i can get. i want to save this tonearm.

i also have an b&o 4002 that has been in storage for a while. everything works on it except for the tone-arm up and down. cannot play a disc. any idea who might give this vinyl player cpr in the metro houston area?

all ears....

Silly question perhaps, but you DID replace the C cell battery...?

He said that the arm was lifting, since the arm will not lift unless there is a good battery, I decided not to bug him about that.

Don C said:

He said that the arm was lifting, since the arm will not lift unless there is a good battery, I decided not to bug him about that.

Click to expand...

Ah yes, of course. Sorry, I missed that.

ps: very well-written digest of the SL-8E. Thanks. I never thought about the little foam disintegrating, will look at mine when it's re-assembled on my Thorens.

My problem is, or was, when I last played it 15 or so years ago, was that the "move the motor" switch caused a click in the speakers. I figure a cap is gone, just never got a round tuit.

i wish i could mate the b&o with the rabco.

the rabco will go up and down, but won't traverse the disc.

the b&o will traverse the disc, won't go up and down.

and no one in metro houston understands this gear at all these days.

i guess it is time for a rega with its more coventional tonearm.

will i be happy with this. sure i will. i auditioned a p3 with a dynavector 10x4 two weeks ago. playing a yuiteru vinyl of art pepper. a knockout.