TASCAM 22-4 Rewind and Fast-forward Not Working Properly

B

BDMonster

New member
Hello everyone, I'm new to this forum. Already I've answered a lot of my questions just by browsing the analog and tascam boards. Thank you.

Last week I bought a TASCAM 22-4, and I've been trying to get it working. My first issue was with the capstan not turning, but I fixed that issue by replacing the missing capstan belt with a large rubber band (I'll buy the actual belt soon). Now I can hear some audio in the headphones when I hit play. I only have one tape, and I have no idea what is on it because I found it in my friend's basement. Right now I am not too concerned with the unit having issues playing tape. My biggest problem is that my rewind and fast-forward controls aren't working correctly.

When I hit rewind (while lifting the take-up tension arm, of course) the unit rewinds only if there are no reels loaded onto the machine. If I load a tape onto the machine, the rewind mechanism acts as if it doesn't have enough force to turn the reels. The same thing happens with fast-forward.

I have the cover off so I can see what's happening, and I notice that when I hit play, the brake solenoid releases the brake bands, but when I hit Rewind/FF, the solenoid doesn't release them. If I intervene, and manually release the brake bands while the machine is loaded with tape, then the machine seems to rewind/FF as it should.

It seems to me, then, that there is an issue with the solenoid releasing the brakes during FF/rewind. I suspect that the solenoid itself is working correctly, because it releases during playback, just not RW/FF. I am left to think that there may be some problem in the signal between the RW/FF buttons and the solenoid. If this is the case, I may be getting myself into unfamiliar territory; I am comfortable in troubleshooting mechanical devices, but I have little confidence in my electronics repair skills.

If anyone has any ideas of what I might do to fix this particular problem, I would really appreciate your input. Similarly, I would appreciate any sort of advice to a beginning tascam reel to reel user (I have zero prior experience with these machines).

Thanks for all of your help so far, and your attention to this issue. I really appreciate it.
 
remove all the rollers and tape guides and clean thoroughly and then lubricate with very fine oil.

Same thing happened to mine.

Your brakes also need adjustment.

Let me know if you need a .pdf copy of the service manual.
 
I'll definitely take your advice. Any recommendations on a particular type of oil? Should I just lubricate every surface the tape comes in contact with (excepting the heads and pinch roller, I assume)?

Regarding the brakes: I had read in another thread that the brakes can be adjusted, but mine seem to be riveted in place - I see no way to adjust them, but I am probably just missing something.

If you've got a service manual pdf that you're willing to share, that'd be a huge help. I'd really appreciate it.

I'll try lubricating it when I have time today, and then I'll post the results.

Thanks for your response, GCalo!
 
I had basically the same problem with an Otari MX5050BII-2, (FF/REW worked but PB didn't) but this was a power supply problem. The Otari PSU was fairly complicated though. (The selenoids had a separate rail, which had a bad rectifier, probbaly caused by a bad cap -- replaced them both.) The selenoid wasn't getting power in Play mode.

I also don't have a SM for the 22-4, GCalo? I don't know if the 22-4 selenoids operate the same way, for a relatively smaller machine it still seems pretty solid.
 
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Is the tape shedding and sticking to the guides stopping the rewind /fast forward from working?

Alan.
 
For oil go to an ACE hardware store and get the Zoom Spout oiler.

Remove, clean, and oil the two tensioner pulleys as well as the capstan roller.

I need your e-mail to send a .pdf.
 
witzendoz, the tension arms do seem to have 100% tension on them when I hit RW/FF. It could be that the tape is sticking. I guess lubricating the surfaces would make a significant difference here.

GCalo, you can email me at: amakutesuppai@hotmail.com

I really appreciate all of your help.
 
I had same prob w/my unit. It's a simple fix. Use denatured alcohol to clean the metal surfaces, and then oil all sparingly

I will send .pdf manual copies tomorrow (Friday) to all who asked.

Just got back from a long trip to SoCal.
 
.pdf's sent. If anyone else just advise.

I have owner's and service manuals.

Advise which or both.
 
.pdf's sent. If anyone else just advise.

I have owner's and service manuals.

Advise which or both.
Click to expand...

PM isn't working for some reason, so here is a gmail address that will work: both would be great. replace the AT w/ @

nchevatarevichATgmail.com

Thanks.
 
BDMonster said:
witzendoz, the tension arms do seem to have 100% tension on them when I hit RW/FF. It could be that the tape is sticking. I guess lubricating the surfaces would make a significant difference here.

GCalo, you can email me at: amakutesuppai@hotmail.com

I really appreciate all of your help.
Click to expand...

DO NOT! lubricate the tape paths, if you get any oil on the tape you may as well throw it away. The lubrication everyone is talking about is the rollers / bearings. Clean the tape paths and remove the tape shred, it is very sticky and will jam the tape and stop it moving. If you play the tape again and it returns the tape is gone (too old) and you will need new tape.

Cheers

Alan.
 
You lubricate ONLY the rotating parts that have bearings.

Do clean thoroughly as Alan has suggested however.
 
Results

Ok, I've cleaned and correctly lubricated all of the parts in the tape path. I cleaned the volume control pots with tuner cleaner. I've also adjusted my brakes according to the service manual (thank you very much GCalo). I also ordered a new capstan belt from TASCAM so I can replace the crusty rubber band that I have on there currently. I ordered a brand-new tape pancake from ATR, and loaded it onto 7" reels using a cut-up cardboard box and a record turntable. I even went to the hardware store and bought a few new washers to replace some that were missing. Unfortunately, I've still got problems.

The brake solenoid is still not releasing during FF/RW, and according to the service manual (section 6-7-2), it is supposed to. During play mode, the solenoid releases the brakes, and the tape plays correctly (I even made a brief recording to test things out, and when it played back just fine, I remembered why I am even working on this in the first place). During FF/RW modes, the solenoid does not release - the brakes stay on, so the reel motors don't move. The service manual has some information about the brake solenoid circuits, but it's moonspeak to me - I can't make much sense of it. Does anyone have any ideas about how I might get these brakes working correctly? Am I going to need to buy new electronics?

Also, I know this is a long shot, but I'm missing the head cover and the feet for this 22-4. If anyone knows where I might be able to score these parts, that'd be cool.

Thanks for all of your help, everyone; one day soon I'll have this thing up and running, and I'll be able to record my album on it. Looking forward to the day...
 
A few possibilities:

a) the solenoid control circuit might be bad. Here's something else to try. With tape from reel to reel (not across heads) hold up L & R tensioners and hit FF button simultaneously. If if FF's OK, then you know the brakes are releasing.
b) there may be a fuse controlling the circuit. You have to remove the outer case to get to them. As you look at front of unit, the fuses are on the right on a board. I am not sure there is one there for that circuit. Check SM for fuse application. I would but a bit jammed at moment.

Just makes no sense with adjusted brakes the don't release on FF or RW. You may have to look at logic schematic as to where ther release is for the brakes during FF & RW.

Sorry I cannot be more on point. Try a) above and report back.
 
I wish I knew you needed belts. I have a source that will supply both belts for less than what you'll pay for just the drive belt from Tascam!
 
Problem Solved

Thanks to GCalo's service manual, I finally fixed the problem. Thank you.

The motors run in two modes: PLAY (Play and Record) and FAST (FF/RW). My brakes were releasing when in Play/Record mode, but not in FF/RW, which suggested that there was something wrong with my FAST circuit between the buttons and the brake solenoid. There were only a couple possibilities - one resistor and one transistor. The brake solenoid was certainly good, because it worked in PLAY mode. Betting on the easier fix, I bought a pack of 10K ohm resistors from Radio Shack (I was surprised that they still sold them there). I surprised myself by doing an acceptable soldering job with the resistor - I guess I'm not as bad with electronics as I thought. Then I fired up the machine and...it didn't work. The resistor was not the problem. I replaced the resistor three times, hoping that my problem was a mere shoddy component. No luck.

While thinking about what to do next (specifically, purchasing the transistor) I was casually cleaning the control PCB with a q-tip and alcohol, and I noticed that there were some little specks on the board. When I wiped them with a q-tip, they came off, and took the top laminate layer of board with them. It seems that the previous owner must have spilled some sort of corrosive onto the board. Having another lead to follow, I checked the pathway for the FAST circuit, and sure enough, a big hole burned right through the pathway. I ripped apart the wiring for an old computer fan, soldered my resistor to it, and then bypassed the entire PCB pathway for the FAST circuit. With fingers crossed, I turned on the machine, hit fast-forward, and screamed for joy when the brakes released. Both FF and RW now work as they should.

All that's left to do now is adjust the reel tables (one of them is a bit wobbly), and re-adjust the right brake (it is now too loose). Ideally I'd like to get the heads adjusted, but that sounds like a lot of money in test tapes and measurement equipment that I am not able to spend right now. I'm guessing that having a professional do it would cost quite a bit as well. Ultimately, I'm not sure how important the head adjustment really is.

Hopefully I'll be purchasing a mixer in the next couple days. I'm looking at a cheap one made my Behringer that ought to do the trick.

Thanks for all of your help (especially GCalo with the service manual). If anyone has anymore advice for a beginning reel-to-reel user, I'm all ears. Also, any advice or opinions regarding head adjustment would be appreciated.
 
This is great news, but if you have a wobbly reel table you might have a bad motor bearing!

Check the two screws (I believe 2.5 mm) on the brass base of the reel table. The cover must be off to get to them but I assume you have that off now.

If those are tight and it wobbles I have a spare motor you can have for $20.00. It's nearly brand new.

If the motor bearing is bad it may have caused the circuit prob you discovered!

Anyway, great news, and keep us posted.
 
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