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View Full Version : Coleco ADAM tape drive gone 'crosseyed'



falter
February 22nd, 2016, 08:55 PM
Don't know why but I had a hankering to play Dragon's Lair. So I pulled out my Adam which, apart from occasional transformer hum, seemed to work okay. Anyway, it would load the game alright, but after the last man died, it would go to a Loading screen, and then eventually the drive would stop and it would hang there. Thought nothing of it.. just reset (I never get past that first level anyway). But then it changed -- the drive started running slower and slower, and it would rewind, click, start reading a bit of tape, then rewind, then click again. Eventually after a few checks and resets, all it would do is remain stationary making a clicking sound, like it was stuck. So I checked it out more carefully with a tape out, and noticed the two drive wheels were running in opposite directions. The left is running clockwise, the right, counter. When a tape is in, they essentially deadlock eachother.

Wondering if anyone has run into this. Strange it just started today.

KC9UDX
February 23rd, 2016, 01:15 AM
It's supposed to do that. That provides tension so the tape doesn't unwind.

The hubs don't drive the tape; the capstan and pinch roller do.

I'm not sure what to make of the click, but I'd check the drive belt, if there is one. Also make sure the punch roller hasn't melted, and isn't about to.

Bungo Pony
February 23rd, 2016, 02:47 AM
I'm not sure what to make of the click, but I'd check the drive belt, if there is one. Also make sure the punch roller hasn't melted, and isn't about to.

The Adam tape drives don't have belts. The spindles are both controlled directly by motors.

It almost sounds like your copy of Dragon's Lair has a problem. Was it ever shut off with the tape in the drive? I can't count how many games I had crap out because I powered off the computer with the tape in the drive.

I used to make backup copies of Adam cassettes with a dual cassette drive. You have to transfer the Adam cassette into a regular cassette shell and do it that way, but it was well worth the trouble simply to make backups.

stangman517
February 23rd, 2016, 06:40 AM
Silly question but have you cleaned the heads?

I remember the first DDDs manufactured by Coleco weren't the best. If its the one with the spring in the front this is the one I always had trouble with.

Those DDDs are getting harder and harder to find.

KC9UDX
February 23rd, 2016, 06:53 AM
I used to make backup copies of Adam cassettes with a dual cassette drive. You have to transfer the Adam cassette into a regular cassette shell and do it that way, but it was well worth the trouble simply to make backups.

What's unusual about the Adam cassette shells?

falter
February 23rd, 2016, 08:01 AM
What happens when I turn it on is there's this low click-click-click sound, ad infinitum. Usually when you have a data pack in and turn the machine on, the machine tries to rewind it. I've even put in datapacks where the tape is at its middle, but the drive won't rewind it. It just sits there and clicks clicks clicks. If I tap it gently, *sometimes* it will attempt to do something.. maybe rewind, then try to read a bit, then rewind again.. and do that until it gradually stops and goes back to clicking. If I pull the tape out, the two drive wheels are turning in opposite directions, and I think when you put the tape in, they continue to try to pull against eachother, resulting in that clicking sound. The encoder wheel, which I fixed some time ago using the dinky car tire trick, seems to be in good health, so I'm guessing this is some sort of motor or logic failure.

I do have a second drive, unfortunately it's been in pieces and a few of the wires have broken from its little motherboard. On the drive I have now, these wires are actually in a connector that removes from the board... but on this spare drive they're soldered in directly. If I can find a picture of it somewhere, I can resolder I guess, move the encoder wheel (the spare is missing one), and see if that drive will do the job for now.

falter
February 23rd, 2016, 07:54 PM
Did some more research. One fellow online mentioned having the 'tape drive capstans turning in opposite directions' after switching in an AT or ATX PSU when the one in his printer died. My ADAM's printer (where the power supply is) has been periodically emitting a loud hum. It comes for about 5 seconds or so then disappears. It doesn't seem to have any effect on the operation of the machine, but it did seem to be happening more often the last little while I was operating. I wonder if it is failing or causing weird voltages that freak the DDS out. I don't know what the hum is but it's quite pronounced.

Trixter
February 23rd, 2016, 09:15 PM
It almost sounds like your copy of Dragon's Lair has a problem. Was it ever shut off with the tape in the drive? I can't count how many games I had crap out because I powered off the computer with the tape in the drive.

Powered off, or powered on? I thought the trouble was because there was an unfiltered burst of power that went through the heads on power-on, so any tapes in the mechanism when you turned it on had the possibility of getting junk written at the head position. Wikipedia seems to agree...


I used to make backup copies of Adam cassettes with a dual cassette drive. You have to transfer the Adam cassette into a regular cassette shell and do it that way, but it was well worth the trouble simply to make backups.

I guess this is how you "formatted" tapes too, right? (I read that the Adam didn't have the capability to format its own tapes, that they had to be formatted at the factory only)

kyodai
February 24th, 2016, 12:50 AM
In a nutshell the only difference between an Adam tape and a normal audio casette tape is the holes in the "shell". The Adam tapes were made from a rather durable "thick" tape so they could withstand the high winding speed easily. However, most quality 60 minute tapes were of comparable quality and can be used if you drill the "Adam holes" into them.

The "formatting" of Adam tapes is close to a scam scheme. As i said you can use normal audio tapes with the 2 additional holes, but Adam will reject to init a fresh audio tape because it is not "fomatted". Actually the legendary "formatting" Coleco did in the factory for a blank DDP was simply throwing a blank Index Table in the middle (!!!) of the tape. Why the Adam does not contain any command to rebuild the index if it is damaged is beyond my understanding - especially since the INIT command checks the index and overwrites it with a blank index.

To "format" a damaged DDP or ordinary audio music tape you can just copy any working Adam tape onto the target and then reset the index with the "INIT" command.

To read (copy) an Adam tape in a normal dual deck audio casette deck you have to either drill the missing "audio casette holes" into the Adam tape or (temporarily) remove the holding pins in your casette deck (In some decks the tape still alligns very well without these pins). Whats also noteworthy is that the Adam tapes are quite sensible, so turn off auto-leveling and if you have an equalizer put it to somewhere around having all levels on like 70%.

KC9UDX
February 24th, 2016, 04:19 AM
It has two capstans? It's a double sided tape deck?

If so, the capstans should certainly be turning opposite directions. The tape direction and "side" are switched by selecting just one of two pinch rollers to put pressure on one of the capstans.

But if you mean reel hub spindles, can you stop them with your fingers? Is one harder to stop than the other?

falter
February 24th, 2016, 07:02 AM
I'm seeing 'capstans' being used to mean what I think you refer to as the spindles. I'm referring to the two black things that physically drive the tape. The one on the left is trying to spin counter clockwise, the one on the right tries to go clockwise. They are both on at full tilt.. if I remove the tape they just spin at full force in their opposite directions. They are both putting out the same amount of force, which is what causes them to deadlock when a tape is put in.

KC9UDX
February 24th, 2016, 07:52 AM
I'm seeing 'capstans' being used to mean what I think you refer to as the spindles. I'm referring to the two black things that physically drive the tape. The one on the left is trying to spin counter clockwise, the one on the right tries to go clockwise. They are both on at full tilt.. if I remove the tape they just spin at full force in their opposite directions. They are both putting out the same amount of force, which is what causes them to deadlock when a tape is put in.

Could you take a picture?

Here's something I found online:
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