SP10 dis-assembly

[Gerry]

Mark

As David says the BBC PSU usually went with the SP10 MKII/P. It was called SH-10EP. It only works with the SP10 MKII/P. Part of the mod was to remove various components from the underside of the plater and incorporate these within the PSU. I'm not sure sure, but believe these were done in the factory. The BBC then added their own pcbs with additional mods.

There were some of the regular PSUs which were supplied with the SP10 MKII which the BBC played with to allow pitch control and a a remote control. These, as I understand it, will work with any SP10 MKII.
However the remote is where most of the problems lie. In some cases the TT will not start without the remote, so best to check it is included. It is possible to bypass the remote but not always straightforward.
The BBC did various mods at different times, and as yet, I've found little or no paperwork regarding these, let alone circuit diagrams.

Regards
Gerry

[IslandPink]

OK, thanks chaps.
I'm in no immediate rush , this is a dealer item, so I could get a couple of pics and some verbal info from him . Interesting .

I should advertise the 401 first I suppose .

MJ

[Darren]

Hi Mark,

Shouldn't you hear the 401/SP10 together before selling?


Does anyone know of an SP10 MK1 chassis details/drawing?
I have a MK1 here and it's totally different to the MK11.
They both need different plinths. Nothing is the same, even the mounting bolt positions and quantity differ.

Are Mk1s a bit rarer than the MK11s? I don't seem to see many about or much info on them?

[david C]

mkIIs are more plentiful but you do see a steady stream of mkIs on ebay, about 5 since Christmas,

[IslandPink]

Hello Darren
Yes, I should do some listening really. I do think the more testing comparison may be the SP10 vs the Hyperspace . Actually this evening I have no problems with the Hyperspace, sounds really strong in the bass and quick . Perhaps I should practice being relaxed about things ?

MJ

[RSC]

New here, so late to this topic, but I had a 401 from '96 until about '98, when I was introduced to the joys of an SP10/II, which I bought after about 10 minutes of comparison - a friend still runs the 401.

In 2003, I fitted a granite top plinth/armboard (using an SME IV, which I had used on the Garrard, too), which certainly improved over the previous timber-based effort.

My next addition will be a proper plinth, when time allows, using hardwood to fabricate a "box" for the granite to sit on/in, possibly incorporating a suspension system.

[pre65]

What you REALLY want (you know you do !) is the Slatedeck plinth

http://www.slatedeck.com/IMG_8574%20red%20800.jpg

[RSC]

Hmmm, that looks familiar...

Mine's not so wide: the arm runs parallel to the motor unit, rather than at 45 degrees (or so) as in the image.

Made from "Zimbabwe" granite - polished black but speckles in the surface finish - of approx 20mm thickness.

I'll get a photo sorted out soon, if you're interested.

BTW, pre '65, your location: I went to school in Clare, so how come you've put Ashen in Suffolk? (Yeah, OK: Sudbury, your postal town IS in Suffolk).

[pre65]

Yes-i am actually in Essex,about 0.5 miles from the river Stour which is the border.

As you say,Sudbury is my Postal town and Clare (about 3.5 miles) is my local town.

[RSC]

Yes, I know it well: born & bred in that area, rest of the family still in that part of the world - what a small world!

[Greg]

Have a think about plinth material. Obviously stone is good but granite is crystaline in structure which is not the best for sinking energy. Slate, particularly North Wales Slate is made of compressed mud layers millions of years old and it has the naturally incurred Constrained Layered Damping element that makes it preferable for TT support.

[RSC]

Yes, but I've already spent my money - don't think I'll get another plinth past the Mrs, since we haven't had a holiday yet this year...

[Lee S]

Errrr.... Where is the constrained layer in slate please? Surely slate is just... erm... layered??

Have I missed something?

[Darren]

Lee, slate is very constrained, incredibly so....

Guess you have been hanging around the Lenco forum?

[Lee S]

"Constrained-layer damping (CLD) systems are usually used for very stiff structures. (See Figure 3.) A “sandwich” is formed by laminating the base layer to the damping layer and adding a third constraining layer. When the system flexes during vibration, shear strains develop in the damping layer. Energy is lost through shear deformation, rather than extension, of the material." [ref]

"Most CLD applications use a three-layer “sandwich” system that is formed by laminating the base layer to a damping layer and then adding a third constraining layer (Figure 1). Typically, the constraining layer is of the same material as the base layer, but exceptions are common. In this sandwiched construction, when the system flexes during vibration, the damping material layer is forced into a shape that shears adjacent material sections. This alternating shear strain in the CLD material dissipates the vibration as low-grade frictional heat (Figure 2)." [ref]

I think these are both credible commercial papers explaining CLD. I don't think slate on its own, per se, is a CLD system, but rather just a naturally layered material that works well in taming vibration by means other than CLD.

Just an observation really, that, yes, has also been pointed out on the Lenco forum. Not sure who started all this CLD stuff, but to term simple layered ply, or slate, or whatever as CLD is wrong I think. To be correctly termed CLD, I think you would need to bond two slabs of slate to a central, "sandwiched" damping layer that allows vibration and therefore heat energy dissipation in the shear plane.

All IMHO of course, but there is lots out there about passive constrained layer damping (PCLD) and active constrained layer damping (ACLD). I don't really think a slab of slate on its own is either.

Sorry. Just my opinion. Don't wanna ruffle any feathers.

Cheers