Tascam 122 MKII problems....

[Studio-Integra]

I picked up a nice Tascam 122 MK-II...

When I turned it on, de capstan spinned way too fast.
I have had the same problem with my 238.

So, replaced the SMT caps on the motor PCB.

Now, the capstan speed is too low.
VR1 on the motor PCB doesn't give any reaction....

If I turn on the pitch control, I can get the right speed, but as soon as the pitch is turned of, the capstan speed is too low...

Does anyone knows something about this?

 

[westgate]

I picked up a nice Tascam 122 MK-II...

When I turned it on, de capstan spinned way too fast.
I have had the same problem with my 238.

So, replaced the SMT caps on the motor PCB.

Now, the capstan speed is too low.
VR1 on the motor PCB doesn't give any reaction....

If I turn on the pitch control, I can get the right speed, but as soon as the pitch is turned of, the capstan speed is too low...

Does anyone knows something about this?

don't have answer, sorry.
i do have 3 122 mkIIs; 1 works ok, the other 2 run slow, even with pitch control on max. so i too am looking for a fix, etc.

 

[Studio-Integra]

Found it...


I Assumed that, because the Motor + PCB is the same as in a 238, I could use a service manual of the 238....

But speed adjust in the 122 MK-II is done on de Pitch PCB


What have I done:

I replaced de little silver SMT caps:

That solved the problem of the speeding capstan.

Then, I heard a tikking noise when I played a cassette...
I found that it was caused bij:

I didn't have the right belts fot this, but found a solution:

Now it runs smooth! but, too slow...
Finally I found out where to adjust the speed and now it runs perfectly!

Oh... I've put in a little sheet of orange plastic behind the counter window.... Now it matches perfectly with my DA-30 MK-I

I'm very happy!

 

[westgate]

Now it runs smooth! but, too slow...
Finally I found out where to adjust the speed and now it runs perfectly!

I'm very happy!

where and how did you adjust the speed?
any special tools needed?

thank you.

 

[Studio-Integra]

Behind the pitch control knob, on the inside of the machine, is a little PCB...
On that PCB is one variable resistor.... you can't miss it.
Turn off the pitch control and adjust that variable resistor.

You can do it by ear... but better is a test cassette with a sinus tone and a frequency counter...

 

[westgate]

Behind the pitch control knob, on the inside of the machine, is a little PCB...
On that PCB is one variable resistor.... you can't miss it.
Turn off the pitch control and adjust that variable resistor.

You can do it by ear... but better is a test cassette with a sinus tone and a frequency counter...

do i need to disassemble anything to get to this variable resistor?
would a small screwdriver work or ?

i'm obviously new at working on these tascams so i appreciate any help i can get. the one that works is a fine sounding deck.
i do have a service manual on my hd to look at.

 

[Studio-Integra]

If you take the hood off, you can reach the variable resistor.
It is adjustable with a normal screwdriver.
You don't need to disassemble anything in the recorder.

 

[Studio-Integra]

Just a picture of my cassette and DAT decks:

DA-30 MKI
122 MK-II
112 MK-I
238
134

The 134 is the only one I bought in goodworking condition.
The others were defective wen I bought them and they are now all fully restored

 

[sarika2376]

cool.

that set up is beautiful.i love taPE DECKS.I GOT a 238 and it runs too fast sometimes and too slow other times.it's pretty loud too but i use it all the time anyway and just pitch adjust as necessary.but if it's an easy problem to fix i'd love to try.does it sound like it needs a new motor or just some sautering or something?

 

[Studio-Integra]

I think your 238 is suffering the same problem as all others... the little silver SMT caps on the motor PCB.
You can replace them with ordinary capacitors
The bipolar 3.3uF can be excluded.

Only the 1uF, 10uf (3x) and 4.7uF needs to be replaced.

It worked on my 238 and 122 (they share the same motor)

 

[sarika2376]

thanks

thanks i'll have a look see into that.or try to find someone to help me do it.

 

[ha8pw]

Hello. Do somebody have the circuit diagram of this capstan motor? I am looking for it...

 

[Studio-Integra]

I'm afraid there isn't any...

The PCB is named as a complete part in the manual of the decks that used this motor.

 

[davegarn]

I picked up a nice Tascam 122 MK-II...

When I turned it on, de capstan spinned way too fast.
I have had the same problem with my 238.

So, replaced the SMT caps on the motor PCB.

Now, the capstan speed is too low.
VR1 on the motor PCB doesn't give any reaction....

If I turn on the pitch control, I can get the right speed, but as soon as the pitch is turned of, the capstan speed is too low...

Does anyone knows something about this?

make sure the pinch roller pressure and back tension are okay. The speed control is R502 located on the bottom of the pitch control board.

 

[KevinW]

I see that this is a 7 year old post. I’m looking for a couple of parts for my Tascam 122MK2. I just changed the loading belt and began testing it out and found that it works correctly until the pitch control is engaged. It turns out that the pot, R501 has been damaged and is open. I am looking for either the pot alone or the complete board. This 100K pot is quite unique and not easily replaceable. If anyone has parted out a machine out there, please let me know. I also need the red the button cap for the front/rear input switch. My father, being blind, had the button removed and taped over because of accidentally depressing it and not understanding why he didn’t have any sound. He bought this machine new in June 1987. He recently passed away in February at the age of 102. I have more than 1100 cassettes to go through. Also 400 reel to reel tapes. I’m using his Sony 650 for that. It will take me a while.

 

[sweetbeats]

Greetings. Let me check on the pitch control pot. Is it a push-pull pot to turn the porch control function on and off or does it only sweep?

The button cap I should have. Can you post a pic or a link to a pic of your other buttons? I need to know if the base color is light brown or dark brown.

[EDIT]

When you say “pot” are you talking about a little board-mounted trimmer?

 

[KevinW]

Greetings. Let me check on the pitch control pot. Is it a push-pull pot to turn the porch control function on and off or does it only sweep?

The button cap I should have. Can you post a pic or a link to a pic of your other buttons? I need to know if the base color is light brown or dark brown.

[EDIT]

When you say “pot” are you talking about a little board-mounted trimmer?

I think I have attached a photo. I removed the potentiometer (pot) from the board thinking that I could find a replacement but it is very unique in more than one way. I would prefer the entire board including pot. I emailed Tascam and somebody replied saying they would check as I supplied the correct part numbers from the service manual. I did find a guy on ebay from Spain who has a lot of parts but the pitch board isn't listed. I wrote to him asking but have not had a reply. I could also use a level knob as my dad had filed a large notch in it to reference where it was pointing. He was quite a guy. I grew up with many hifi recording devices and audio equipment. He had a large studio Ampex 400A he bought in 1952 that he had for around 10 years. He also had multiple portable machines including a Nagra Kudelski 3. He was into recording like some sighted people are into photography. He tuned and repaired pianos up until he was 90. He had an amazing ear for sound. Sorry, off topic. In any event I would like to get this unit working correctly. Many thanks.