De-magnetizing tape heads

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Yes, that does help; I have always been suscpicious as to whether the cassettes work as well as standard de-magnetizers- alas, you have answered my question :yes:.

Although, I must say that I think heads should be de-magnetized a little more often than every six months... a little bit of magnetism (as low as 0.2 gauss) can cause a big loss in recorded sound quality. 0.7 gauss will erase high frequencies on commercially recorded tapes.
 
AudioOrigami said:
yea ive got 1 ...i have had it for years ...was disapointed that i could not hear much sound improvements with it...

j7

Talking about the normal ones you plug into the wall...?

Those things have always confused me for some reason; I was always confused about the issue of polarity, and I was never quite sure whether to move it up and down across the tape head, or side to side in the direction of the tape travel when I actually owned one.
 
Hi,
in my oppinion this "cassette" type demagnatizers don`t work well enough. Most of the user`s manuals I`ve seen state that the entire tape path is to be demagnatized. This includes all three heads (if a 3-head deck) capstans and tape guides, everything which can get magnetized through a contact with the tape. So a friend of mine gave me such a cassette and I`ve tested it. It has one cell battery and it comes in contact only with the PB head. So in my oppinion in no way can this device develop the required field with the strength needed to do this job. I prefer a hand demagnatizer. It makes quite a good job if you read and follow the procedure which the manual states. With a hand demagnatizer you can (and should) demagnatize also your screwdrivers and tools.
Best regards,
Plamen
 
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The cassette units that "play'" do not work well at all. You need to use the proper type that plugs in the wall. You need to use it properly or you can magnetize the heads or something else. Turn the deck off when doing this!

-Chris
 
My old AIWA F990 does the job automatically. It’s a clever circuit with a relay, activated for a few seconds, every time the deck is switched on. Maybe there’s something to DIY here.
Then again, only the head and no surrounding parts will be demagnetized.

/Hugo
 
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It's like a television degaussing circuit. The playback amp should not allow any DC current to flow in the head windings, and there is no reason for most tapes to become magnetized in one pole unless your tape gets stuck to a magnet, or or use a cheap cassette deck. The exceptions are the really old machines.

Most people do more damage demagetizing their own deck than if they had just left it alone.

-Chris
 
Yes, that`s true with the demagnetization. I have a DM-10 this is a good one, I`ve demagnatized all my screwdrivers, also I`m doing a demagnatization on all screws and nuts because I`ve read that this should be done. But demagnatizing a deck with it is a little awkward. First of all you don`t get propperly in where you should. and you actually don`t know what you`ve done because I don`t have a meter for this. Small circular movements, someone says, switch it on and then get in, someothers say get in and switch on, switch always off far away from the deck. Deck is sure off, but how can you do a damage. Also it is said to demagnatize all the path where the tape travels, this means heads, guides and also capstans. But the capstans on the dragon for example are driven by a PLL motor and both capstans have round magnets glued on them. Can you damage these magnets with the demagnetizer and so damage your capstan motors ?
Generally, away from motors ? What do you think and how do you do this ? Best regards,
Plamen
 
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