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Tape eraser

S

SFM-Ptgal

Here's my problem: I had an old tape eraser/degausser where I erased my carts. It burned out. Now I need another one.
I've been watching ebay for cheap ones but their duty cycle is nonsense. 1 minute on 20 off...

Now the probably impossible:

How can I make a home made tape eraser?...

regards,

Pedro M.
 
I haven't seen a tape eraser in so long. My high school's radio station had one, I don't know if it's still there.

Get a strong bar magnet and rub it on the tapes
 
I have about a half dosen (maybe more) brand new, still in the box, hand held bulk erasers. They are "Benjamin" brand, made in the USA, rated for 1 minute on, 20 minutes off. They do fine for erasing carts. I will be happy to share. I think we paid about $50 each for them, but wil sell them for less than we paid.

Contact me off line at kzqxfm(NOSPAM)atAOL.com You can probably figure it out, but remove (NOSPAM) and substitute @ for "at." I hate spammers.....
 
SFM-Ptgal said:
Here's my problem: I had an old tape eraser/degausser where I erased my carts. It burned out. Now I need another one.
I've been watching ebay for cheap ones but their duty cycle is nonsense. 1 minute on 20 off...
Click to expand...

Pedro,

I'd just buy one from Chuck. ;D
BTW, that's not an unusual duty cycle. A bulk eraser is like a transformer without a secondary, so there is no load. It's the nature of the beast to get hot.
;)

As long as you take only 5-10 seconds per cart, and wait as least as long between erasures, you can get quite a few done before it overheats. If it has an internal thermal breaker, it will pop when it's hot. Otherwise, when it gets too hot to touch, give it a rest.

Kind Regards,
David
 
right on david. when my old eraser ran hot,heck i'd put it to good use, ironing shirts,made a great taco warmer,lots of uses...the secretaries loved when i buffed their rear end with it.you just have to be creative...
 
menotti1 said:
right on david. when my old eraser ran hot,heck i'd put it to good use, ironing shirts,made a great taco warmer,lots of uses...the secretaries loved when i buffed their rear end with it.you just have to be creative...
Click to expand...

They make a great travel iron. ;)
 
SFM-Ptgal said:
Here's my problem: I had an old tape eraser/degausser where I erased my carts. It burned out. Now I need another one.
I've been watching ebay for cheap ones but their duty cycle is nonsense. 1 minute on 20 off...

Now the probably impossible:

How can I make a home made tape eraser?...

regards,

Pedro M.
Click to expand...

You can make one out of an old power transformer. It is not a project for the faint of heart or for folks who have lots of other things to do.

Basically, you disassemble the transformer, leaving the coils intact. You’ll find that the laminated pieces of iron that make up the core are actually single pieces that look like the letter “E.” They are arranged so each alternating layer overlaps, making a square with two holes in it. The coil goes through those holes. Your first task is to figure out how to delaminate the pieces without breaking something. Then you restack them so they are all going the same direction. You place the coil over the new stack of laminations so it sits between each space between the three legs of the laminations, like it was before you disassembled it. When power is applied to the primary, the three legs act as pole pieces, and they will erase a tape if the transformer is big enough.

This sounds easy, but it is not. Finding a transformer that can be disassembled is not as easy as it looks, and new transformers can cost more than you are prepared to spend. You will also have to experiment with finding the right transformer that will develop enough magnetic flux to do the job. Many years ago old TV power transformers could be used, and they were cheap and easy to get. Just rob one out of a junker tube type TV. You won’t usually find those any more.

In the process, you might also be exposed to potentially hazardous chemicals (PCB's in older ones) and you will have a lot of fun with getting the glue to release so you can delaminate the thing. Some just fall apart, while others are impossible to take apart. It just depends on the glue the manufacturer used.

Your end result may have an even shorter duty cycle than something you could buy, or it may not erase tapes very well. Depending on how you package it, it may also be a potential shock and/or fire hazard. It is way easier to just buy a new one.
 
I may get laughed at for this, but if I was in this ssituation, I'd buy a cart eraser / splice finder from www.cartguys.com. Or look for used ones on ebay. The unit cartguys sells, does not use coil magnets to erase the tape. Instead it containes two erase heads like what you would find on most 1/4 inch reel decks.

R
 
If you've time to let the carts run through (At high speed), Robert's idea is cost effective. If you're in a rush, do a Google for "Garner eraser' and see if there might be one out there for sale cheeeeeep. I gave a couple of them away several years ago. They are made for pretty much continuous duty, are thermally protected, and will take even high oputput tape signals down to waaaay below the noise level. They also weigh a ton, take up space, and draw beaucouip power from the outlet.
 
One point to remember when using a bulk eraser is to leave the eraser on while you slowly pull the tape away. Then turn the eraser off when the tape is away from the eraser. If you turn the eraser off while the tape is still on the eraser coil, you'll get a collapsed field on the reel of audiotape that you can hear as a thump, thump, thump noise in playback.
I remember this from my production days.
Also ITC made a cart machine size cart eraser that erased a cart while it spun it to find the splice, positioning the splice past the heads and also collapsed the field slowly using electronic circuitry.
 
SFM-Ptgal said:
What can I expect from an eraser like this one?

http://i23.ebayimg.com/04/i/000/a7/c3/f790_1.JPG

Thank you!
Click to expand...

It should work. I remember seeing these back in the 70's or 80's and they were fine for most general purpose applications. I think they were really designed for cassettes which use 1/8" tape. With patience, it should erase a cart OK. The picture you showed is smaller (but sleeker looking) than the Benjamin which I think was also sold under the "Robbins" name. It probably has the same duty cycle.

Bulk erasers with long duty cycles are usually large square boxes about 12" by 12" square and 4" or 5" deep. They will weigh about 40-50 pounds and require at least a 15 amp 120 volt (some are 220 volt) dedicated electric service.

By the way, am I right in thinking you are in Portugal? Maybe I’m just imagining that from your screen name. If you are not in the USA, you need to look for an eraser that is happy with 220-240 volts 50 cycles (HZ), unless you have 60 HZ current in your area. A 60 HZ device like this will not be happy on 50 HZ. It will get hot very quickly. It simply takes more iron in the core of the inductor to pass the lower frequency.
 
Chuck said:
SFM-Ptgal said:
What can I expect from an eraser like this one?

http://i23.ebayimg.com/04/i/000/a7/c3/f790_1.JPG

Thank you!
Click to expand...

It should work. I remember seeing these back in the 70's or 80's and they were fine for most general purpose applications. I think they were really designed for cassettes which use 1/8" tape. With patience, it should erase a cart OK. The picture you showed is smaller (but sleeker looking) than the Benjamin which I think was also sold under the "Robbins" name. It probably has the same duty cycle.

Bulk erasers with long duty cycles are usually large square boxes about 12" by 12" square and 4" or 5" deep. They will weigh about 40-50 pounds and require at least a 15 amp 120 volt (some are 220 volt) dedicated electric service.

By the way, am I right in thinking you are in Portugal? Maybe I’m just imagining that from your screen name. If you are not in the USA, you need to look for an eraser that is happy with 220-240 volts 50 cycles (HZ), unless you have 60 HZ current in your area. A 60 HZ device like this will not be happy on 50 HZ. It will get hot very quickly. It simply takes more iron in the core of the inductor to pass the lower frequency.
Click to expand...

Thank you for your advice. I'm actually bidding on a TEAC E-2 bulk tape eraser that runs on both 50/60hz.
 
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