Technics SP-10 Doesn't Spin

[breadhead]

Hello everyone,

I recently purchased a SP-10 MKII in "as is" condition so no complaints about the seller. It powers on and the strobe lights but that is it, no platter movement at all. I have minimal electronic experience. I have looked at the troubleshooting section here, Library Downloads - Vinyl Engine

I have taken some voltage readings but my low level skills don't allow me to interpret them, many of which are way off. Below are the readings I got:


E15 26.01V 28.18V

TR118 E 6.06V .408V
C 21.17V 28.13V
B 6.69V .121V

TR115 B .771V
C .162V

TR116 B .103V
C 6.07V

TR117 B .113V
C 6.07V .46V

D101 26V 0V

D106 6.7V 6.01V

D107 6.01V 0V


P3 20.52V

Any help would be greatly appreciated!

Thank you,
Jim

 

[east electronics]

Jim ...

None of the readings you posted is of any use unless you have a working SP10 open in front of you Or you have repaired at least 50 of them and you know them inside out ...

I don't think that you will find any of the above conditions in the forum easily ...

This is not a repair for a NB ,,,seek for expert help ...

The usual suspects though for direct drive Technics are
Dirty switches and bad contacts
poor soldering
Dried capacitors
But it gets even worst
IC that drive the motor
IC that produce or sensors that control the frequency

And so on and on

 

[Drummerboy2]

make sure the motor is NOT locked down with the the transport screws in the locked down position. Also check the power supply output when cable is connected and make sure they are correct. You should be able to find that info on the vinyl engine site.

Hope this helps

 

[Notinthislifetime]

You need to check the supply voltages to the drive circuit. What you are looking at is the control board and from recent experience those look correct. The service manual is available from the vinyl engine and contains the voltages you should be looking for at rest, bracketed numbers and at 33.3rpm, boxed numbers.

Good luck

 

[6L6]

You need a digital oscilloscope or an analog scope and frequency counter to get one of them set right...

But anyway, look for leaky caps, burnt resistors, and the like, in the PSU first, then the table innards.

Take a bunch of close-up, well-lit, in-focus photos and post them here.

 

[breadhead]

Hello again and thank you all for your advice so far. I began to test voltages in the drive circuit but stopped after the first test as the readings were way off. I got 32.24V at a1. I tested TR38 and got these: 12.20V, 70mV, 11.47V and 12.46V, 3.5mV, 11.73V. I do have the service manual but as I stated, I am not well versed in electronics but am very capable in learning. Any help, again, much appreciated.

Thank you,
Jim

 

[sgrossklass]

There is a troubleshooting flowchart on page 6/7 which you'll want to follow (item (A)). So far you have only checked a single supply voltage (+32.5 V), which is a bit low but not worryingly so (plus I don't know how accurate your meter is).

Looks like the base connection of TR38 comes from TR127, so this one will need to be checked, followed by TR152, TR106 and TR107. Heh, the flowchart says check voltage and waveform on TR127 and TR151-154, not bad. So I guess you'll want to do that.

 

[sendmedown]

Technics SP-10MK2 problems

I recently purchased a Technics SL-1000MKII SP-10MK2 Direct Drive Turntable on eBay that is in remarkable condition. However, when I received it three days ago I noticed the seller did not have a motor lockdown plate only three screws in the platter. The deck gets power but the TT motor does not engage or move the plater at all, I cant spin it freely it's like both brakes are locked. The eBay seller made these comments in his listing, "*Please read* Unit powers on and motor spins but needs service. It changes speeds when different RPMs are selected but there is wow and flutter from time to time so the motor needs some service. The start-stop button seems to be set on start so the motor spins always when powered on. The springs in the hinges of the dust cover need replacement to keep the lid up. RCAs are live and with audio when the cartridge is in place."

This is my second TT of this model, I purchased my first in Hong Kong in 1976, and I loved and used it for 30 years selling it to a German man in 2005. I regretted that and finally got my chase to get one again.

I am clearly a newbie on this forum, but please I am in desperate need of help and advice on what I should do first. Since I do not have the test equip. I brought the deck to a local electronics shop, this guy has been doing repairs for 40 years, I sent him the schematics and service manuals alone with all I could find online that sounded relevant.

 

[rayma]

Rely on your local tech but get a quote if possible, or at least the hourly rates.

Seller should at least offer a partial refund since the faults were not as described.
Also consider filing a damage claim with the shipper, if the seller is not responsive.

 

[JP]

Is the motor hub sitting high?

 

[JohnnoG]

A SP10 MkII might be able to be fettled with and achieve a platter rotation if a EE unfamiliar with the product has a poke around under the hood.

The TT can also be returned to function to a level of performance that is very sought after.
To achieve this the TT would be better in the hands of an individual who fully understands the TT and all the needs for a refurbishment that are required to be considered and check out.

 

[sendmedown]

Thanks to you both for the advice, yes I did file a claim with UPS. The seller is saying he did nothing wrong. JP, I will meet with the local repair tech and I will try to see if the motor is sitting high. My feeling is I don't think so because I exposed the manual brake and solenoid to see if it was locked up and it was not. I would have noticed if the motor nub was higher than normal, but I will check. I did break it loose with a little force, it still would not spin but one rotation sounds like a bad disk break on my car.

 

[JP]

That’s exactly what it’ll sound like in the scenario I described in the email. The only other likely possibility is that the bearing is trashed to the point of binding, but I find that very unlikely.

 

[sendmedown]

If the motor hub is high how exactly can I tell this and what could be done about it. I sent an email to Bill in Virginia hoping if I have to send it off to be repaired he would take it on. I don't mind upgrading the caps and any other board-level stuff I have my own shop where I repair mobile devices. I can read a schematic and follow instructions in the service manual, however, I don't want to risk making things worse at this time. I have been wondering if it makes sense to buy another TT that is working and use it for parts?

 

[sendmedown]

Thanks again for both your input. John, I am planning on doing just what you are recommending. JP I have spent several nights reading many of your posts here on the SP-10MK2, great insight, and experience from you both.

 

[JohnnoG]

Hi sendmedown, my skills are quite limited, I do have a reasonable understanding of the basics.
Most importantly I have been fortunate to have been able to meet with some very skilled individuals and become friends with them, HiFi is my hobby so I don't use it to gain in anything but musical encounters.
Beyond this being involved in collaborative investigative ventures are where I fit in, I do enjoy being involved with a concept design that has been taken on to be developed into a working end product.

 

[JP]

This is an extreme example - this unit was shipped with the platter on.

If you send it out make sure you're clear on what you're getting. A lot of 'upgrade' service is just caps and maybe some diodes without any detail work or measurement of actual performance.

 

[sendmedown]

JohnnoG, thanks for the input, I think it will be a while before I look into any special projects with the SP-10MK2, but nice to know I can come to you for that.

JP, my unit was shipped with the platter on, however, I know for sure I did not see what your picture here is showing thank God. I to, can't imagine its the bearings, but if it was, how difficult would it be for someone like Bill in VA to deal with?

 

[JP]

What I pictured is actually a simple repair, so I'd hope that is the cause. Next likely cause if it's binding is a bent spindle.

Bill is a competitor and a customer so I'm not going to speak to his work one way or another.

 

[sendmedown]

Ok, good to know, I did not realize you worked on these TT from that perspective. Can you give me some ideas of what it might cost for you to do the work?