Tascam M-216 some Potentiometers not working

[csxdy]

Hello!

I have a question:

I recently bought an old Tascam M-216 for 50 Euros.
I have already ordered some better Op-Amps and modded
the 4 Vu-Meter lights to "cool-blue" (they were not working)
thanks to this excellent Forum!
but there are some eq and pan Potis not working.
Has anybody a clue, what i could try as i really want to
make this mixer full working?
I have already disassembled (sorry for my english, i am from Austria)
one input pcb and removed the old Op`s.

Thanks

 

[csxdy]

No one?

 

[mdainsd]

You might ask up in the Analog Only forum. Thats where the guys who know these things hang out.

 

[csxdy]

Thanks, i figured it out myself.
If somebody wants to know, just ask me

 

[Beck]

Thanks, i figured it out myself.
If somebody wants to know, just ask me

When you solve a problem or end up answering your own question, you should share that answer for others who may have the same problem in the future.

I've found cold solder joints on the M-200 series mixers that will cause the problem you describe. I've even found some pots where the solder was missed altogether at the factory during assembly. Simply resolder the leads on the offending pot.

 

[csxdy]

Hi!

Ok, sorry you are right.

I could solve the problem with opening the Potentiometers.
Then i saw that the small metal pins that are making the contact
to the bottom of the potentiometer were loose.
The plastic which was holding the pins in place was broken,
i think it got brittle.
So i put some super glue on it, to put the little metal
with the pins back in place.
So now they are working again.

 

[Beck]

Awesome! Nice fix! I've seen a couple like that as well.

 

[csxdy]

Yeah, it works and now i am waiting for the better op amps
should arrive tomorrow....

 

[csxdy]

Hello again!

I fixed the problem and did some mods to the Tascam.
Thanks to this awesome Forum!
Here is what i did:

I repaired the non working Potentiometers
Changed the Op Amps ( and they are now socketed)
changed the Lights of the Vu Meters to "cool blue"

here are some pics:

 

[Beck]

Nice work! What op-amps did you decide on?

 

[csxdy]

Thanks!

As you mentioned in an older post i took 5532 A op-amps.
Do you know anything else that i could do for upgrading the sound?
it is very good now, but i just LOVE modding
I read somewhere in the forum that recapping the Psu is a good thing,
but that seems to be really much work, and i dont know, which parts i should get for
replacing the old ones...