Tascam 38 Capstan issues

[Piper99]

Hi,
I'm new to this forum but not to analog. Need help. Here we go.
Had my 38 in a road case for 30 years... cleaned the rubber goop ... changed the belt/ pinch roller. Had selenoid issues, brought it to factory tech(maybe the last one alive), corrected the issues gave it a once over - said your good to go.
First day of recording no problems (only about 2 hours put on machine) second day - "the noise". Ends up there's rubber on a washer on the capstan shaft next to the flywheel that deteriorated. Fine.. took it apart cleaned it up, tried fiber washers in place... everything seemed ok then speed starts to slow down and it stops.
Ends up F505 & F506 fuses blown. Replace fuses take out fiber washers replace with nylon washers. Hook it all up - same thing happens. Replace the fuses, pack it up and bring it back to the tech. He thinks the capstan motor might be damaged due to the fuses keep blowing. Capstan(motor runs) spins when tension arm engaged. Let me know what you guys think. It seems difficult to find a replacement motor.

 

[Smithers XKR]

Hi,
I'm new to this forum but not to analog. Need help. Here we go.
Had my 38 in a road case for 30 years... cleaned the rubber goop ... changed the belt/ pinch roller. Had selenoid issues, brought it to factory tech(maybe the last one alive), corrected the issues gave it a once over - said your good to go.
First day of recording no problems (only about 2 hours put on machine) second day - "the noise". Ends up there's rubber on a washer on the capstan shaft next to the flywheel that deteriorated. Fine.. took it apart cleaned it up, tried fiber washers in place... everything seemed ok then speed starts to slow down and it stops.
Ends up F505 & F506 fuses blown. Replace fuses take out fiber washers replace with nylon washers. Hook it all up - same thing happens. Replace the fuses, pack it up and bring it back to the tech. He thinks the capstan motor might be damaged due to the fuses keep blowing. Capstan(motor runs) spins when tension arm engaged. Let me know what you guys think. It seems difficult to find a replacement motor.

Hello Piper, its a brilliant open reel recorder. I use analogue recording gear but not an expert with maintenance. It may be something clogged up causing strain on the motors. A simple clean up and service could sort it. If the motors are blown then they can be replaced relatively cheaply. Also it may be an input Capacitor that has blown which is basically a protection device from input voltage overload. The old capacitors were electrolitic and fluid based wheras the newer more modern caps are all solid state and much more robust electrically. As I say I am a novice so hope this is of a little help.
There is a guy here called Clamsterdam who is a total guru with anything tape related. He has rebuilt a load of vintage tape machines.
You should get in touch... hope this helps mate

Kind Regards... Smithers

 

[Piper99]

Hello Piper, its a brilliant open reel recorder. I use analogue recording gear but not an expert with maintenance. It may be something clogged up causing strain on the motors. A simple clean up and service could sort it. If the motors are blown then they can be replaced relatively cheaply. Also it may be an input Capacitor that has blown which is basically a protection device from input voltage overload. The old capacitors were electrolitic and fluid based wheras the newer more modern caps are all solid state and much more robust electrically. As I say I am a novice so hope this is of a little help.
There is a guy here called Clamsterdam who is a total guru with anything tape related. He has rebuilt a load of vintage tape machines.
You should get in touch... hope this helps mate

Kind Regards... Smithers

Hi Smithers,
Good to hear from you. I'm just hoping all the motors are fine. Like I said, I brought the unit back to the factory tech who serviced it yesterday and hopefully it's something other than the capstan motor and will resolve the issue. I briefly looked online for a replacement motor and they are scarce. I'm like you not an expert in repair of this unit.
I would like to get advice on anything else I might need to do to make sure the unit is in pristine condition. It's the heart of the whole operation, if it goes that's it. I'm more comfortable with analog, that's all I know and where the times are at it's not supported, but they try to duplicate it.
Thx

 

[Smithers XKR]

Hi Smithers,
Good to hear from you. I'm just hoping all the motors are fine. Like I said, I brought the unit back to the factory tech who serviced it yesterday and hopefully it's something other than the capstan motor and will resolve the issue. I briefly looked online for a replacement motor and they are scarce. I'm like you not an expert in repair of this unit.
I would like to get advice on anything else I might need to do to make sure the unit is in pristine condition. It's the heart of the whole operation, if it goes that's it. I'm more comfortable with analog, that's all I know and where the times are at it's not supported, but they try to duplicate it.
Thx

Thanks Piper
Search out the guy Clamsterdam on this forum. He knows everything about tape machine stuff. A real guru xxx

 

[Smithers XKR]

Thanks Piper
Search out the guy Clamsterdam on this forum. He knows everything about tape machine stuff. A real guru xxx

Dont worry Piper everything can be repaired, dont give up. I repaired my Atari monitor for a 50p capacitor!

 

[jamesperrett]

Are you using old tape? Particularly Ampex, Quantegy or Scotch (3M)?

 

[sweetbeats]

The capstan is belt drive, right? With the machine off are you able to get the capstan shaft spinning just by twisting it with your fingers? And is it smooth and quiet when you do this? Does it keep spinning a bit once you let go? Im asking all this to verify the shaft can spin freely, and there’s no noises the come from the shaft assembly or motor when you do this.

When powered and spinning, how easy is it to stop the spinning grabbing with your fingers? Like keep the tension arm raised and try to stop the shaft. It should be impossible. It should be even difficult to slow it down. What happens when you do this?

 

[Piper99]

Hi,
Sorry for the delay. So I brought it back to my tech. All the motors are fine. He had to clean out the take up reel motor, the capstan belt he said was too small. I bought it off ebay from Bob's elect. Which he said was the correct size. The flywheel was too tight against the friction plate. Capstan motor ok. He tested everything out said I'm good to go. He charged me $30 for a new belt and $50 labor, which I was relieved and grateful.
Yes only using new tape (ATR), which I think is the only option at this point.
In the meantime I was fortunate to buy a pair of DX-4D's off of Reverb for $150 free shipping and a RC71 remote off of ebay for $230. Which I really needed and they only appear ever so often for sale.
I'll have to adjust to using the DBX units, I know everyone will have their own stance on it, but at this point I'm committed and getting very close tk start laying tracks.
My next project is refurbing my Ampex 354. My Tascam tech referred me to a factory Ampex tech, so in time... I'm also trying to sort out besides mixing down to 1/4" and cassette, Cd's and Digital. I picked up a Behringer istudio to use with ipad. Just trying to download app to these unsupported ipads. Any guidance for anything is greatly appreciated I'm attaching some pics of where I'm at.

 

[Piper99]

Me again, I just wanted to post what I found when the noise started. Evidently everything that was rubber in these units turns into goo. I had to take off the flywheel clean it up and fabricate nylon washers to replace the rubber one.
My tech took the metal washer put it in between the nylon washers. Put the correct belt on, cleaned out the take up reel motor and readjusted the flywheel - against the friction plate.
It was a learning experience I never took my unit apart before and now I've been in and out a dozen times.
I have motorcycles from the 70's so it's the same deal.
Thx

 

[Piper99]

While I'm here, attached are some pics of my Ampex 354. I've owned it since the 90's never used it or powered it up. Waiting for when the Ampex tech (George) has time to devote to it. Let me know what you think.
Also one of my bikes 1970 Bonneville awesome bike runs great.
Thx

 

[RRuskin]

Re: DBX - Align your machine with the dbx in bypass. Don't record too hot and you should get results that rival digital when it comes to being noiseless.

 

[Piper99]

Hi,
What levels would you set them at, and this would be in bypass mode? Then when recording engage it. I assume when engaged the levels are lower.
Lmk. Thx

 

[RRuskin]

Hi,
What levels would you set them at, and this would be in bypass mode? Then when recording engage it. I assume when engaged the levels are lower.
Lmk. Thx

Assuming machine & meters are calibrated, playback a 1kHz tone @ Ovu. The level should not change more than +-1 whether dbx is in or out. Then record a your own 1kHz tone and make the same comparison on both input and playback from both heads. I used dbx I for decades and tended to print no hotter than +1 on peaks. I'd go quite a bit lower on bass & drum to have plenty of headroom and no artifacts. BTW - The playback head is to be used for alignment. Once heads & electronics are in agreement, all work is done from the record/sync head.

 

[Piper99]

Thanks for clarifying, this helps alot.

 

[13Pieter]

Hello, I am having the same issue with my Tascam 38, but I believe that I have dug in a little further, and the symptoms differ slightly from Piper99 in that when the tension arms are engaged and the capstan begins to spin my fuses @ F505 and F506 do not blow. All transport functions work properly. Now I have traced the specific issue to a single wire that goes from the power supply PCB at position 16 to pin 6 of P502 on the Control PCB. With P502 plugged into the Control PCB and pin 6 of P502 pulled from the connector F505 & F506 do not blow and all transport functions are present. With pin 6 of P502 plugged in the fuses blow but all transport functions remain. This specific wire carries the 24vDC signal and I am obviously experiencing a large enough current surge that it is blowing the fuses but the resistor is so far back on the Power Supply PCB that I can't probe it to calculate the over amperage. I have traced the schematic and from Pin 6 of P502 which goes to the Capstan Motor Assembly PCB and the Capstan Solenoid via the Control PCB. The Capstan Motor Assembly PCB is not the issue. I have pulled and tested all corresponding transistors and diodes on the Control PCB and they all check out. I have also tested this scenario with the Capstan Solenoid wired pulled from the Control PCB and the fuses still blow. My next idea is to check out the Power Supply PCB but I wanted to talk with out with someone who may have experienced this issue previously.

Thank You,

Pieter O.