Teac 80-8 transport problems

[lassoharp]

Hello,

I have an 80-8 that no longer rewinds or plays. The capstan works fine but the take up reel doesn't move. The rewind problem was a slow developing problem that used to happen only after the machine had been ran for several hours. Now rewind, and FF as well, no longer work. Any ideas as to what the problem may be?

[The Ghost of FM]

I had a similar problem with my TASCAM 38, which was one model year newer then your 80-8. In my case, it turned out to be the reel motor itself which needed to be replaced as having it taken apart and giving it a proper cleaning as well as replacing some worn internal parts proved to be more costly in labor then just direct changing the motor, which as a part that may still be available, cost around $120 new from TEAC parts and is relatively quick to change out from a technician's bench time perspective. If you need both motors changed, obviously the repair bill will be double.

Though there are other possibilities with regard to faulty regulator transistors on the transports logic board, they don't allow the motor's performance to fade and then die. They simply die like a light bulb blowing and the entire transport comes to a halt so I believe those should be ruled out.

There's also a possibility that the problems lays elsewhere and there are other experienced users here who I am sure will chime in with their thoughts on what the problem may be. It might also be an issue of the brake solenoids getting on in age and becoming stuck in the braked position so, there's a basic need to open up the deck's front panel and have a peak at that. Do you have the service manual for the deck? If so, that will give you the documentation to see how to take things apart, check the settings and adjustments and so on. Or, if you're unprepared to open it up, try seeking out a qualified service shop in your area.

Cheers!

[A Reel Person]

I'd check the brake solenoids & make sure the hub brakes are releasing properly and completely. Also make sure the solenoid for pinchwheel actuation (up/down) is working properly.

[lassoharp]

Sounds Good. Off to check break solenoids. Unfortunately I don't have a manual. The machine is opened up on my bench. Could you tell me where to look for the solenoids?

[lassoharp]

OK I think the solenoids for the supply and take up reels are disengaing correctly. I think it could be the take up reel motor. It doesn't move at all now during Play, REW. or FF. Sometimes giving it a spin by hand will get it going but it will only go for a short amount of time then it stops.

Is there a definitive way to verify whether this motor is bad? When any of the transport functions are engaged I get a reading of 17.8 volts AC for each motor lead. Don't know if this is correct without referring to the manual though.

There also doesn't seem to be any bearing noise or vibration from the motor.

I also suspected the big start cap. I removed the leads and checked it with an ohmmeter. Charges the way most normal caps do - no short or open. Looks like maybe one side of the can is for each motor. A good question would be whether this caps is used for starting only, or is it responsible for helping to keep the motors running as well.

[A Reel Person]

Once you get the front cover plate off, you'll see the 2 plungers that work the works. If the rubber deteriorates, it could gunk up the works and cause transport issues like you describe.

[sweetbeats]

Can anybody help lassoharp out? I only have the schematics and owner's manual for the 80-8.

I concur with both Ghost and Reel on the brakes and the pinch roller.

Quick brake tests:

1. Raise the right tension arm with no reels loaded and press PLAY.
2. What happens?

1. Again, with no reels loaded, raise the CUE lever up so it latches. If I understand the 80-8 correctly, this should release the brakes and allow the hubs to freewheel.
2. Can you easily spin the hubs? Should be able to spin them with a thumb and forefinger and they should keep spinning.
3. If you can't spin them easily or they drag and stop spinning when you release your thumb and forefinger the brakes are dragging or not releasing. The brakes either need adjusting or the solenoid is sticking.
4. You'll want a service manual for adjusting the brakes.
5. Sticky solenoids can be due to a rubber cushion that has gone gooey, or the solenoid is just tired and needs replaced.

Now for the pinch roller...

1. With no reels loaded raise the right (takeup) tension arm and press PLAY.
2. The pinch roller should pop smartly into position against the capstan shaft.
3. Press STOP.
4. The pinch roller should pop smartly into the park position.
5. If it is lazy or takes time to engage either position the solenoid cushion could be sticky, the linkage could need cleaning/lubricating, or the solenoid could be tired.

Do the tests above and post back the results and we'll go from there.

[lassoharp]

Originally Posted by A Reel Person

I'd check the brake solenoids & make sure the hub brakes are releasing properly and completely. Also make sure the solenoid for pinchwheel actuation (up/down) is working properly.

The hub brake for the take up reel doesn't fully release(only momentarily, then reengages) during Play, Rew, or FF.

Can this(solenoid) be fixed or adjusted or do I need to get a new motor?

[lassoharp]

Originally Posted by sweetbeats

Can anybody help lassoharp out? I only have the schematics and owner's manual for the 80-8.

I concur with both Ghost and Reel on the brakes and the pinch roller.

Quick brake tests:

1. Raise the right tension arm with no reels loaded and press PLAY.
2. What happens?

1. Again, with no reels loaded, raise the CUE lever up so it latches. If I understand the 80-8 correctly, this should release the brakes and allow the hubs to freewheel.
2. Can you easily spin the hubs? Should be able to spin them with a thumb and forefinger and they should keep spinning.
3. If you can't spin them easily or they drag and stop spinning when you release your thumb and forefinger the brakes are dragging or not releasing. The brakes either need adjusting or the solenoid is sticking.
4. You'll want a service manual for adjusting the brakes.
5. Sticky solenoids can be due to a rubber cushion that has gone gooey, or the solenoid is just tired and needs replaced.

Now for the pinch roller...

1. With no reels loaded raise the right (takeup) tension arm and press PLAY.
2. The pinch roller should pop smartly into position against the capstan shaft.
3. Press STOP.
4. The pinch roller should pop smartly into the park position.
5. If it is lazy or takes time to engage either position the solenoid cushion could be sticky, the linkage could need cleaning/lubricating, or the solenoid could be tired.

Do the tests above and post back the results and we'll go from there.

When Cue is latched, neither brake releases( I've got the back off so it's easy to observe the brakes). So neither hub spins freely

Pinch roller snaps into and out of position well. Looks crisp

With capstan arm held in position, and pressing Play, Rew, and FF - brake on Take-Up reel doesn't disengage. Supply Reel brakes do disengage during all three

[lassoharp]

GOT IT!!!!!

My problems were apparently due to the position of the solenoid housing. It had slipped to the left causing the plunger to not stay engaged(therefore brakes would not disengage). Fixing it was a simple matter of loosening the 4 set screws, then moving the assembly housing slightly to the right. Plunger stays engaged (brakes disengage), and VIOLA! Transport is behaving normally again!

What appears to have been happening is that the physical distance of the solenoid housing had become large enough to overcome the magnetizing force of the coil, causing the plunger to incorrectly disengage.

Loosen the set screws and shove it to the right a little and you're good to go.

To Ghost, Reel Person, and Sweetbeats I sincerely thank you for your help!

[The Ghost of FM]

Good to hear and glad we were able to point you in the right directions!

You now owe us $3000 dollars in small, unmarked bills!

Cheers!

[sweetbeats]

Hey that's great!

Good job and congrats!

That slide adjustment effects the brake tension so adjust accordingly if the brakes seem not be stopping the reels effectively or if they seem too strong.

[vincedog3]

Another 80-8 still lives on. Now that is a happy ending. Well done.