Vinyl recorder part ID please - groove speed part

[David34]

Hi trolls,

Cutting a disc and my groove speed controller is now starting fast, then slowing down.

We’ve cracked open the module/unit and worked out which part may be faulty, but of course the part number has been ground off.

I am on good terms with Souri, but can not afford one month postage there, and one month back. I have customer back log.

Can anyone on here please ID this part? I’m sure some of you will have this problem in the future, or may already have..??

Thanks in advance!

[Discomo]

Is there a reason why you suspect this part to be faulty?

I previously had a problem with a faulty din plug from the main unit to the motor. This was causing erratic voltages and slowing down of the motor and finally killing it.

Repairs by Souri go fast. Matter of a few days. Of course sending in Corona times may seriously complicate things, especially from outside Europe.

[DJ2000]

my electronics isnt the best but thats a transistor, with part number taken off like Souri does makes it harder to find replacements but I would have thought a transistor if gone faulty it would either work or not work (gone short or open circuit)

if the speeds fast then slows have you tried switch cleaner in the speed controller dial? might just be dirty ive had issues with cracks and noise from bass dail on the main unit and switch cleaner cured that it could be a simlar issue but with the speed dial

[Tinplate]

The mysterious part is LM317 - adjustable positive voltage regulator.

[markrob]

Actually, its an LM317 adjustable voltage regulator. It may be bad, but also make sure the shorting plug is faulty. The shorting plug is removed if an external pitch control is used. If the plug is open, the regulator goes full on. If the pass transistor in the LM317 fails shorted, you will have the same issue.

Mark

[David34]

You guys are great. I am so grateful. Let's hope we can get somewhere with this.

It's the downtime that I am avoiding, not Souri. I like the guy, never had any problems with him or his equipment, blanks etc.

It's just taking too long to send things and get them back.

Thanks again!!

[David34]

Just an update - that part changed, we added a heat sink to it, and cutter working fine now. Groove speed back in action!

Can’t thanks you guys enough. A $3 part! So I bought 3!!