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Wooden Broadcast Tonearm

T

Turntable

A question for you guys who have been doing engineering for a while... turntables, remember those? :)

I have acquired a very nice turntable from a friend at a local radio station, always wanted one, now I got one. It's the Technics SP-10 mk2. The tonearm on its plinth is a very simple design, it has a fixed counterweight and tracking force is instead established via weights that are mounted to the bottom of the headshell above the cart. It has no adjustment for anti-skate whatsoever. The arm is made of dark wood, looks like teak or mahogany. This is a brute-force, no-nonsense tonearm which performs very well with a few modifications. I have no idea of the manufacturer, and that's what I need to know. Any ideas anyone?

Thanks.

Alan
 
Here's an update:

Affixed to the top of the arm shaft, there was a P-touch label which stated "DO NOT PLACE OBJECTS ON TONEARM...DAMNIT!!!!". I removed it, and underneath there is a logo showing a platter and tonearm within a square border.
 
These are/were good tone arms... I've seen more Micro-Trak's in radio station than probably any other and they've always stood up. You had to really screw it up to burn a styrene 45 when properly paired with a Stanton 500.
 
Tonight I got another SP10 mk2 table (no plinth) with another microtrack 330 arm. Believe it or not, I'm running a high compliance cart (Signet TK7Ea) with the damn thing and it actually works alot better than you would think. Both Stantons are completely intact but the stylii were totally shot (picture Yugo meets Peterbilt...). :) Oh how I love rescuing old gear... lol...

BTW I'm always looking for cart decks...

-A
 
Some, if they weren't made by micro-trak, were made by Gray Research...
 
SirRox..remember the original Gray "Viscous damped" tone arms that looked like a big-ass sewig machine arm?..used to house a Shure cartridge
 
Jeff Laurence said:
SirRox..remember the original Gray "Viscous damped" tone arms that looked like a big-ass sewig machine arm?..used to house a Shure cartridge
Click to expand...

If anyone happens to have a spare slide out cartridge mount for a Gray 16" tone arm, I'd love to hear from them. I need one, since I have a tone arm that is missing that part. A GE VR II in good shape would be a welcome additon.

You can email me at chuxgarageATaol.com Just take out the "AT" and put in "@".
 
If you think the Gray's were something, check out the dual arm pickup here.
[/quote]

Great Scott, I have that Theremin issue, and modified the design to use all octal tubes.
Then I 3/4 finished the project. Still waiting for the spare time to appear.
Got the tone generation osc. working easily. The volume blocking osc will be a little trickier.

Wood arms were considered to have fine natural damping, and in those days, cartridges were very stiff.
Hence, the tonal properties of the arm were much more evident.
Wood arms sounded better than plastic and tracked better than metal.
 
I built the theremin. And learnt thereby the value of a physically robust chassis, particularly if there's RF involved. Not being musically inclined, I gave it away and went for the 'photorythmacon' (color organ) which Pop Sci featured a few months later.
I was in somebody's junk storage the other week, and saw a little bottle of Damopening Fluid which was used with the Gray Research arms.
 
I was building the theremin in 2003, for a wedding present, and we gave a different gift, as it was taking too long.
I had to cross-reference other designs to come up with osc frequencies, as the miller coils are pure unobtainuim today.
I think the text completely missed reference to osc frequencies.
Wiggliness is not permissable in the theremin, or any other RF design, as you pointed out.
What year did you build the theremin? Did you have proper store-bought L, or have to hand wind also?

Just how viscous is the fluid? Like gear oil? And was the pivot-joint immersed in this stuff?
 
You're upsetting my Altzheimer's here, but...
In the 60s, I believe, was the theremin. One of the mags later showed a solid state one which was substantially more stable, OA2s being what they were.
If memory serves, the Gray Research arms had a large - inch or two in diameter - ball on which sat a semicurcular piece as the suspension, the fluid was put on the assembly to oil it. It was a silicone oil, loked to be maybe 70 weight or so. It's been a While :):)
 
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