Thorens TD-125 MKII problems

[nimrod1941]

I own a TD-125 that I bought new many years ago. In all of these years it has not had a lot of use. I have been using my Sony 2251 more. I an now replacing the Sony with the Thorens and am experiencing problems. When I trun the Thorens on it will run for approximately 5 minutes and then stop. The strobe lite remains on. I can change the speed or turn the table off and then back on and it will start again. With the table stopped, I have turned the table manually thinking I may have a bad spot in the motor. The table does not resume turning. I must change the speed or turn off and then back on to get it working again.
Does anyone have any suggestions as to the problem and a remedy?

Thanks,

Jim Walton

 

[BRN]

It sounds like there is something wrong with the electronic speed control. If you do a internet search for manuals and repairing the electronic speed control there are sites a threads on how to do it.

 

[rayma]

When I trun the Thorens on it will run for approximately 5 minutes and then stop.

Possibly an electrolytic capacitor on the pcb. I'd replace them as routine maintenance regardless.
Thorens TD125 Manual - 3-Speed Belt-Drive Suspended Chassis Turntable - Vinyl Engine

 

[K.A.B]

It's like Rayma writes, because you have to replace all electrolytic capacitors, I've replaced many. It's hard to find the right value, but it does not matter if you the closest to size but not less in value. Do not touch anything else.

Good luck.

Anders

 

[nimrod1941]

Thanks for the help. I am not an electronics wiz but have built many Dynaco and Heath kits in the past. I do have the right equipment and materials. I will have to find the correct caps.
Would it be possible for one of you look at the component board and locate the correct caps to change? I noticed that all are numbered. This would be a great help.
Can you give me any information about where I may obtain the correct caps?
When I get to the board I may decide this is more than I am comfortable with doing. I will then start looking for a competent shop to carry it for repair.

Thanks again for the information,

Jim

 

[kevinkr]

Mouser at one time had all of the caps (almost all odd values by today's standards) required for my MKI which has different electronics. Vishay makes good ones in axial packages.

The schematics and service manual are available on Vinyl Engine - The Home of the Turntable - you must be a member to access them.

The board is extremely brittle and will crack easily in the slightest mis-hap. It may be easier to completely remove it for repair.

 

[rayma]

I am not an electronics wiz but have built many Dynaco and Heath kits in the past.
I do have the right equipment and materials.

If you can desolder using solder-wick, it should be doable, just don't stress the pcb.
Cut the old parts off first, leaving about 1/4" of lead to make desoldering easier.
Practice on some scrap pcbs first until you are comfortable and don't harm the foil.

Replace C2 and C4, each 1000uF/35VDC. Those are the only electrolytics on the pcb.
See if this cap fits the pcb hole spacing. TVX1V102MCD1LW Nichicon | Capacitors | DigiKey
Other caps are film or ceramic types, and are probably ok and should be left alone.
There is a lamp in the oscillator feedback circuit, make sure it's ok.
You can try to redo the adjustments after it works again, check if the pots seem clean.

 

[K.A.B]

I found a thread on Vinylengine about mk 2 pcb restoration I hope this will help you. https://www.vinylengine.com/turntable_forum/viewtopic.php?t=58160

Anders

 

[rayma]

I found a thread on Vinylengine about mk 2 pcb restoration

Yes, it's worth buying a can of DeOxit just for this job, while the board is out.
Hosa D5S6 CAIG DeoxIT Contact Cleaner 5% Spray

 

[nimrod1941]

Thorens TD-124

Thank you guys for the help. I am ordering the parts tomorrow and purchasing DeOxit. I really believe this is something I can do. Wish me luck. I will update on the results.

jim

 

[rayma]

I am ordering the parts tomorrow and purchasing DeOxit.

When using the DeOxit, use a very small amount, on the lowest spray setting of the nozzle.
That is, use as little as possible. Then actuate the switch many times, a dozen or more,
to help remove the crud. Then repeat this again.