The Incredible Technics SP-10 Thread

I've read these posts.
It's okay...but the benefits will be minimal ...if any.
From the moment it starts to wear, a bit more of the ball "sees" the trust plate and after a point the wear is minimal...it takes years of continuous operation to wear it out.
The problem with these inverted bearings is that they run essentially dry.
At the moment i am working on a solution that will make it immersed in oil.
That will really make a difference in maintenance.
 

6L6

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The biggest improvement you can make after changing C146/7/8 is to align the PLL as page 10/11 No.6

SP-10Cap146:7:8.jpg

These guys?
What about the series resistors? Would matching them down to a RCH make any difference?

SP-10_PLL_adjust.jpg

And this?

Noted. Thanks!!
 
Well...i have opened three of them (SP-10 and SP-10MKII) and they looked bone dry to me.
A minimum of oil was "felt" more than seen on the spindle.
Maybe the oil used was too thin and "evaporated"?
And the bushings are not the type that hold oil in them too.
Maybe the ones i saw were poorly maintained...
In a no compromise rebuilt it's advised to check wear to find if you're after new bushings.
 

6L6

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I've completed the re-cap on one of the boards (save for one cap I didn't realize was a bi-polar electrolytic, so I need to order a few of those...)

When I get into the remainder of the 2nd board I'll grab some photos.

It's a straightforward process, and although the PCB are thin with thin copper, it's made up for by there being silkscreen on both sides of a single-layer board. :)
 

6L6

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IMG_05761.jpg


So once opening the table up and getting to the solder side of the PCB I find one things that are less than optimal... This being the worst offender. There was power resistor replaced on the board, and on this table it was made by somebody badly connecting 2 resistors in series. When they did this the traces lifted and this mess was made.

IMG_05811.jpg

Here's the new resistor, with bends in the leads to let things heat up without stressing the PCB any more. (In this photo it looks like the bend blocks the pot - it's only camera angle, and the pot is easily accessible.)



IMG_0577.jpg


Luckily there was a few unused holes in the PCB where it could attach, and the lift trace could be left completely alone.

IMG_0578.jpg

Ok, this one is all my fault... It's a very fragile board, 31yr old, with surprisingly thin copper. Luckily there is a few places where I could re-attach the lead and make the circuit.

IMG_0586.jpg

The board with beautiful new caps.

IMG_0582.jpg

Dead soldiers

IMG_0580.jpg


With the PCB off I can see the production date of the motor. I was in 3rd grade of elementary school that day. :)
 
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Hi. For your power resistor installation you have to realized that there is still risk of applying stress to the PCB traces. The proper way to mount an heavy part, such as this power resistor, is to bend the part leads as shown. Then mount the part in such a way that the lead bend is touching the top of the board. This way the part cannot push on the bottom PCB trace, and the part cannot pull out on the pcb because it is soldered from the bottom. Also if it was me I would put pieces of heatshrink on the long section of exposed leads to prevent shorting if the part is bent by accident.

If you look at the old TV HV/Drive PCB you'll see that they always mount power parts this way. Just my two cents.
 

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