INFO wanted: SABC Mark3 TT

[Steerpike]

I have MOST of an old SABC "Mark3" that I want to get back into nice working condition (like the ones shown in the SRPS site here )
I'm missing the right-hand control panel (the one with the black start knob). I wonder if anyone who used them can tell me what its exact functions were, and what buttons and lights were on it. Or maybe someone has a good close-up photo?

Thanks.

(I suppose an original replacement motor is too much to hope for)

[Shonver]

Hi Steerpike

What is a MK3? Was it manufactured by SABC?

[ghostinthemachine]

Goodness... now thats unobtainium!

I also have that pic here on the PC somewhere but only that. Maybe Ampdog can shed light...

Why not try to get in touch with former SAUK employees?

[Steerpike]

What is a MK3? Was it manufactured by SABC?

Hi S.
As far as I know, it is/was the last incarnation of the so called "Dok Viljoen" turntable made by the SABC workshops in the 1960s. I remember seeing them in the old Commissioner Street studios when I was about 6 years old - which partly fuelelled my fascination with audio machinery. This thing would make Gates fanatics envious.

I'm not sure if many made the transition to Aukland park - or if they changed over to SP10 in the new building.

Pictures of mine I have here
http://web.eject.co.za/s8nspawn/hifi/ak/#sabctt
and I have a link to a slightly better photo in the Radio 5 studio here
http://web.eject.co.za/s8nspawn/hifi/ak/5studio.jpg

If I can at least find an accurate description or photo of the right control panel I will make a replica, using the left one (motor on/off + 3 speeds) as a style guide.

[ghostinthemachine]

Maybe the other panel contained a "pre-monitoring" function... like the Revox control panel used to control the SAUK SP-10 machines.

[Steerpike]

Maybe the other panel contained a "pre-monitoring" function... like the Revox control panel used to control the SAUK SP-10 machines.

That's quite possible. Five illuminated pushbuttons, so it must have done more than just start the platter (the round black knob is the 'instant start' clutch control - all I know so far).

Any photos of that ReVox panel? Just for interests sake. Was it a locally made custom item, or did it come from Switzerland ready-made?

[ludo]

Hello Steerpike

Now this may all be old news, even wrong, and I've not seen one of those before, but some ideas that you might consider. An elaboration on GITMs idea.

In a broadcast setup you'd have two outputs for this type of deck. One for prelisten/CUE, and one for TX (transmit) The CUE is always active. It's a handy way for the DJ to find the spot he wants the tune to drop in at, without it going to air. The TX output would have a mute facility that rapidly unmutes the signal after the record is up to speed (and in TX "mode"). There was apparently a rule of thumb to (manually) turn the disk about 10cm back from where one wants it to start playing (to the TX output) after hitting the play button. So maybe the START-STOP button lifts/lowers the platter. If those TTs connect the disc to the platter as you describe on your webpage, I guess it would want a moment for the stylus to stabilise in its natural position and for things (the mat) to stop slipping etc. If the RIAA preamps are built into the box, like with the TD524 and EMTs, the output stages of those preamps is the handy place to mute things for the TX outputs.

The large black knob could be a pitch control? Useful for folks that know what a BPM counter is and are into that sort of music. (They will all burn in Hell )

So that might cover the knob and three of the illuminated buttons (CUE green / START-STOP orange / TX red) on the right panel. The third (orange one next to the knob) might just be illuminated to indicate that the platter is up to speed? I suppose there was some sort of strobe/PLL controlling it?

You have the left panel for 33/45/78/on/off, so it looks like the above could make sense?

[Ampdog]

Jeepers; going back some time ...

They resemble the Neumann turntables that were used by the SABC in the 50's when I did vacation work at the SABC. (The description also fits.) Only we had the pick-up about 1cm from the 'cue point' - the start was instantaneous. The lift of the very light top platter was less than 1mm to engage. Those turntables used a 16inch (41cm) platter to accomodate the resin-coated aluminium record discs used for temporary records at the time. But that just a bit of history (and vague at that), no help with the question. Hell, nobody from those days is alive any longer. My report on my work had close-ups, but is long since buried in the probably no longer existant vintage records of the university.

Sorry.  Sic transit gloria mundi.

[Steerpike]

One for prelisten/CUE, and one for TX (transmit)

I agree these must be some sort of control for the cue/on-air system. But I think they must also control the mechanics. The black knob is DEFINITELY the clutch engage switch - I remember so well watching the.. um what would you call them? . back then the announcers didn't do anything as laborious as start turntables, a lowly operator did that, the announcer just announced...
Anyway, I remember the operators starting the playback with an emphatic flick of the wrist on that round knob.

But with the clutch disengaged (platter lowered) you cannot rotate the LP by hand to back-cue it. So there must be a system to lift the plater, yet not have it motorised. With the freewheeling platter they could cue up the disc, THEN lower the platter, start it rotating, and finally start the LP  (black knob action) by lifting the already rotating platter.
No wonder they wanted SP10s as a replacement.

I don't have any audio electronics for them, but there is a speed select  board with transistors on it. So I can't imagine if the audio electronics were valve or transistor.

I have been told the motor was an Ampex tape recorder motor, made by Bogen. Similar to the Ampex 351 syncronous motor. No pitch control at all as far as I know.

They resemble the Neumann turntables that were used by the SABC in the 50's when I did vacation work at the SABC.

They might well have 'borrowed' a lot of Neumann design to design this thing.
Back then the SABC had almost unlimited money so they were able to build exactly what they wanted.

The platter is 13 inches - I haven't actually checked to see if there is enough arm clearance to play a 16-inch disc.
The arm bearing looks very much like a cross between an Ortophon RM309 and a Grace.

[ludo]

Ja. I see. All wrong . Oh well.

You've seen http://www.springbokradio.com/LETTERS.html ?? Came via google but doesn't seem to be linked from the SRPS home page. The webmaster might provide you with contact details?

Hopefully Hein (Soundstructures) sees this. He might know something of these devices.

[Family_Dog]

Browsing through the Springbok Radio website, I found a small pic of the SABC turntable.

This is stated on the website:

"THE "DOK VILJOEN" TURNTABLE DESIGNED & BUILT BY THE SABC. MANY OF THESE WERE IN
USE AT SPRINGBOK RADIO DURING THE 1950'S & 60'S"

I remember visiting the old SABC Studios in Commissioner Street as a youngster in the 60s. and I recall the turntable with the sloping sides which certainly loked as if it could play 16" transcription records. I used to have a couple of those one-sided aluminium discs then too, but they are long since gone.


-F_D

[Family_Dog]

Here is the link to the Springbok Radio Home page.
http://www.springbokradio.com/index.html


-F_D

[Steerpike]

The webmaster might provide you with contact details?

Still waiting for a reply to my requests for exactly that.

I'd also like to know if the name comes from the person who designed it: "Dokter Viljoen"  maybe? Who was he? What were his talents?

[mafioso]

Hi Steerpike

I know two technical blokes ex SABC Cape Town. The one gent (Gordon Scott and yours truly), messed around in the 60's with TR3A's and the last time I had contact with him, he was in a home in Pinelands, suffering from Alzheimers.

More recently, about 12 years ago, I spoke with Gordon and he facilitated a meeting with his friend Arthur Churms, another technical bloke at SABC's Rocklands studios, Cape Town.

I think Arthur could have retired by now to somewhere up-country but I'll try and trace him on Monday, coming week. Perhaps he will have some info which you can use.

Your project is interesting - if only to show the Aussies with their Commonwealth bctt a finger

mafioso

[Steerpike]

I think Arthur could have retired by now to somewhere up-country but I'll try and trace him on Monday, coming week. Perhaps he will have some info which you can use.

Ah! Well thanks for looking into it & any info he can remember.

Obviously, the TT can be used with any 'operational logic' circuitry I decide to dream up, but I really like the idea of putting it back exactly how it used to be - or as close as possible, on the outside. So it should "look right" and "behave right" even if it has a 21st century microprocessor doing the thinking!

I wonder too if the blue rubber mat was chosen specifically to contrast with the black of an LP - makes it easy to see the edge of the record, compared to a black mat.