Tascam 38 bomb

The cleaning method I detailed is only a temp fix at best. If relays are the culprit, for this size/type of relay the only solution is to replace with new parts. I’ve only been able to find a direct-fit new replacement one of the three relays on the 38 R/P amp cards. I’ll have to refresh my memory on which one it is and what current part number is. But I know you can get the relays at Mouser or Digikey...it’s an Omron part.

Reflowing the solder joints on the cardedge connectors on the amp cards is also a good idea if they’ve been removed and reinserted a fair number of times. But if you are having issues where signal comes and goes to and from tape in sync or repro and it keeps moving around to the point you feel like saying to the machine “WTH would you just stop and sit still?”, that’s likely the relays.
 
The key parameters of a relay are its coil operating voltage (12 in this case?) and the number and configuration of the contact sets, most are 2 pole change over but some 3 pole C/O and very rarely 4p/c/o.

So long as these factors are met you can fit any relay that will physically go in the space. You could in fact even use a lower coil voltage with an appropriate resistor, better a zener.

Often easier to mount it upside down with wires "sprouting" then fix it to the PCB with silicone snot.

Don't know if the relays are driven by a transistor but if so make DDsure that there is a flyback diode across the coil.

Oh and BTW you should be able to prise the plastic case off. You will probably break the wee "window" where it clips back on but again. Snot.

Dave.
 
Dave,

No amount of prising will get to those potted relays the OP is talking about to which he can't access the internals.

And all the relays are 24V.

Here is a thread regarding the model 38 relays. Post #9 has some relevant info, but I've never found any additional info that actually resolves the question of what currently available parts can be used, unfortunately:

BAD news for Tascam 38 users!

I still have to look for the link to the current replacement for K103.
 
Dave,

No amount of prising will get to those potted relays the OP is talking about to which he can't access the internals.

And all the relays are 24V.

Here is a thread regarding the model 38 relays. Post #9 has some relevant info, but I've never found any additional info that actually resolves the question of what currently available parts can be used, unfortunately:

BAD news for Tascam 38 users!

I still have to look for the link to the current replacement for K103.

Ah! Did not get "potted" I thought they had a clear plastic cover a la Revox A77. So, 24V? Plenty of those about or go 12V and 12V zener. I don't know how much bother it would be to get them off the PCB but solder wick and patience should prevail.

Will check that link now!

Not SO bad news then? It seems the offending relay is a screened type for head switching? If such cannot be found screening a bog S one should not be beyond the wit of man?

Dave.
 
Back
Top