[SOLVED] Tascam 244 Pan control only panning left, is there a service manual available?

Se7en-Costanza

New member
Hey Guys,

I have a Tascam 244, everything is completely operational except for one important function.
The Pan controls on every channel only pan to the left, if i pan it right the signal completely attenuates. The right VU meter doesn't move only the left side does (when the pan control is moved back to the left).
This happens on both Cue and Remix monitoring, and as it happens the exact same on all 4 channels, i believe its something to do with the master part of it, or where all inputs sum.

So in bus "sync" recording i can only record on tracks 1 and 3, but all 4 channels record fine and monitor fine on VU meters when you select all 4 Channels to record instead on sync.

Is there a service manual available that someone could email me: nicholas.d.raffaele@gmail.com, or has anyone had a similar problem and know how to fix? I have good electronics knowledge, i just dont want to be poking around without a service manual.

Thanks
- Nick
 
So I was able to get some schematics to Nick, and I took a few minutes to peruse them myself.

So, Nick, it *looks* like the R-L buss summing amps are actually on the "Power Supply/Output Ampl." PCB. If I'm reading the schematics correctly the outputs of input and tape cue amp boards (where you have your channel faders and PAN pots located) interface with the power supply/output amp board via wiring and mini Molex connectors. SO...because, as you already pointed out, your problem exists across all input channel outputs to the R buss, AND because the problem presents in your metering, I'd start by routing tone to the R buss and start tracing through the circuit on the power supply/output amp board. Its a standard opamp-based input buffer/summing amp using a TL072 to the master fader and then from the fader output to an output booster amp using a 4560. You could have a failed opamp, bad solder joint, or a fader that needs servicing... Could be lots of other things too, but I'd start by tracing, but I put my money on an active component like an opamp, a mechanical issue like a bad solder joint or fader problem. I've experienced issues with those mini ALPS linear faders of this vintage where the wiper no longer makes solid contact with the element. All that was needed was to open the fader up, clean it out, and *gently* tweak the wiper filaments to make more solid contact...had a problem just like yours with the R buss in a 388 I used to own...completely dead master buss on one side...servicing the fader took care of the issue 100%. Also worth verifying each opamp is receiving +/-12V on each of its respective power input pins.

Do you hear ANY noise from the R buss? Even anything crunchy with peaks if you really hit it hard with signal? Or just nothing...totally dead?

Those are some ideas. Check it out and give us an update when able.
 
Thanks for the Manual and your advice!

I thought about the fader, and figured i might be able to check if it is suspect if i could wiggle it and or test it on all points of the fader, and what do you know its the fader! it works fine on the Right from 0 to about 4 on the fader than cuts out after that. So i definitely need to undertake some proper cleaning and re-ajusting the wiper contact. This unfortunately doesn't look too easy to do, cause inside this thing it's packed to the brim with boards and wires and layers and the fader being at the bottom of all of this.

Im gonna attempt a clean and keep you informed.

Thanks so much for the help!
 
So i got to the fader opened it up and the worse has happened, a dead spot right on the middle of the track.
Due to it being on the side where the resistance should stay the same the whole way i modded the fader with a piece of wire which is drilled and hot glued on one side and soldered to the contact point on the other side which you can see in the photos, i tested its operation and it works! Obviously the longevity of this mod is probably not going to be very long, it will hold up until i can order a proper replacement part.

Thanks again for all your help, i could consider this thread solved :)

Photos:
DIY FADER FIX.jpgFADER DEAD SPOT.jpg
 
Well done fixing it! I have a couple of failed faders on my ancient 244's input channels which I should replace. How did you get to the master fader? Did you need to take off the top or could you get to it from the back? Any chance you could give a pointer as to where to buy replacements? I can't seem to find anything that fits here in the UK.
 
Yes good job! Glad it was an easy fix and that’s awesome you were able to find a replacement part. I think I have one of those laying around here somewhere, but you actually found one.

Awesome!

:D
 
The channel PCB's look easier to get to, you might just have to take off all the knobs as i think that every channel pcb is connected, but not entirely sure.

Getting to the master fader was a huge struggle, you have to take the top off, unscrew the faders screws, as well as the side plate that has all the jacks, as well as about 3 other pcb's and a bunch of cables just so the whole master channel section can have enough room to be wedged out, it took about an hour or so to actually figure out how to do it without damaging anything.

I ordered a used replacement from Tascam Ninja i doubt i could find an original one in new condition. Ideally if there are brand new non-genuine ones that are the same value and size that you be ideal.
 
Thanks - I think it will be tricky enough getting to the channel faders.... I think I saw a post here somewhere with instructions how to take the faders apart to clean them?
 
Well the bad part needs to fixed or replaced. The replacement idea sometimes is not so easy but there are hundreds of items out ther from other units scrapped that can be used to replace the part. If nothing else some form of repair might take some research but there are conductive pens for PCB repairs. The smoothness of the part might be the issue.

So tell me the value you need and the length of the fader and I will see if I have one here. I just parted out a 246 that was sent here and the transport controls and power supply are going to Australia on Monday. I also have some new parts here as well. When you search for a part like that you need to specify the length and resistance and maybe the width. The Tascam manual gives you a number but if they don't have the parts then those parts number are a complete waste of time.
I suspect the 246 Master might be like the 244 master. You never know.
 
Thanks! Tascam Ninja describe the mono channel faders (which are the 2 I need) for the 144 as "Single slider 10k Log body length 90 mm" and the text suggest they are the same for the 244. I will try to measure up and also get the width next week when I get home. The stereo mixer fader has a quoted width measurement of 20mm. Trouble is, shipping is such a nightmare to the UK - we have duty and 20% VAT, 20% VAT on the postage and tax collection charges!
 
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