Re: Bulk tape eraser
On 4/30/2017 6:22 PM, Jerome H. Fine via cctalk wrote: Looking for recommendations for a bulk tape eraser for SDLT and DLT IV tapes. Eons ago at Microdata we had a commercial grade bulk eraser which could do 2400' reels maybe a bit larger. I wondered by one day with a new fangled device, a 16k eprom. while a small chat developed by the table where the eraser was, I casually put the eprom on the eraser, and turned it on, just because. one of my otherwise smart colleagues looked with a concerned look on his face and then queried whether that would work with the eproms. don't know that he ever lived that one down. Wish I had it, I'd certainly pass it along. thanks jim
Re: Bulk tape eraser
On 04/30/2017 06:22 PM, Jerome H. Fine via cctalk wrote: >> Chuck Guzis via cctalk wrote: > FORTUNATELY, I had an old voice coil fram a speaker available. It > must have been a large speaker because the coil was a cylinder about > 3" in diameter and about 3" long. The permanent magnet seems to have > a few pounds of pull on any iron object, so I thought it might be > useful. It probably takes about 30 seconds of slowly rotating the > voice coil over the surface of the TK50 / TK70 tape to sufficiently > BULK erase the tape such that the TK70 drive would write on the tape. > Since I believe that the TK50 / TK70 tapes are early DLT tapes, this > method may also be successful, if a bit slow, for a small quantity of > tapes. I've entertained the idea of pulling out one of my old microwave oven transformers, cutting off the "I" sections, so that it's only "E" laminations, and then removing the high-voltage outer windings (easy enough to do with a Dremel--some folks re-purpose these boat anchors to serve as the basis for spot welders and such. Carefully limiting the current with a large incandescent lamp, that should give one a whopping AC field that should take the magnetization out of anything. But...it feels like too much work for an old man. --Chuck
Re: Bulk tape eraser
>Chuck Guzis via cctalk wrote: On 04/30/2017 07:38 AM, Mike Loewen via cctalk wrote: Looking for recommendations for a bulk tape eraser for SDLT and DLT IV tapes. If it's just a small quantity to be erased, there are many Radio Shack videotape erasers being offered, some NIB, all for about $20. I've used one for years on floppies and tapes. It's not for erasing piles of tapes, as there's a thermal overload protector on it, limiting the amount of time that you can use it. --Chuck I don't know if my experience with tapes for the TK50 / TK70 applies, but for what it is worth, here is what was the problem. When a tape has been written by a TK50 drive, the TK70 drive will no longer be able to write on the tape until the tape have been BULK erased. Since I had a number of tapes written by a TK50 and I wanted to use the tapes for producing backups using a TK70, I obviously needed to be able to BULK erase those tapes. FORTUNATELY, I had an old voice coil fram a speaker available. It must have been a large speaker because the coil was a cylinder about 3" in diameter and about 3" long. The permanent magnet seems to have a few pounds of pull on any iron object, so I thought it might be useful. It probably takes about 30 seconds of slowly rotating the voice coil over the surface of the TK50 / TK70 tape to sufficiently BULK erase the tape such that the TK70 drive would write on the tape. Since I believe that the TK50 / TK70 tapes are early DLT tapes, this method may also be successful, if a bit slow, for a small quantity of tapes. Jerome Fine
Re: Bulk tape eraser
On 4/30/17 10:04 AM, Chuck Guzis via cctalk wrote: > Certainly not DLT IV tapes--I've done the bulk eraser thing with them > and the result re-recorded just fine. > Sorry, I flipped DLT and LTO in my mind..
Re: Bulk tape eraser
On Apr 30, 2017, at 10:04 AM, Chuck Guzis via cctalk wrote: > > On 04/30/2017 08:55 AM, Al Kossow via cctalk wrote: >> You may as well run them through a shredder. All modern tapes have >> embedded servo tracks. > > Certainly not DLT IV tapes--I've done the bulk eraser thing with them > and the result re-recorded just fine. > > But then, DLT IV is hardly modern. > > --Chuck I know you can’t run LTO tapes through one, but if I remember correctly you can do at least the original SDLT tapes. We had a heavy duty degausser in the datacenter, up until a couple years ago. The tape library vendor we were using at the time wanted us to degauss tapes prior to reusing them due to all the issues we were having. That meant degaussing 100’s of tapes a week. Normally contractors would do it, but in an emergency, I’d do it at times. With the later tapes, you had to run them through something like 4 different ways, otherwise they were still readable (which is why I’m pretty sure we were degaussing SDLT tapes). As I recall, DLT IV tapes only had to go through once. Zane
Re: Bulk tape eraser
On 04/30/2017 08:55 AM, Al Kossow via cctalk wrote: > You may as well run them through a shredder. All modern tapes have > embedded servo tracks. Certainly not DLT IV tapes--I've done the bulk eraser thing with them and the result re-recorded just fine. But then, DLT IV is hardly modern. --Chuck
Re: Bulk tape eraser
I'll add that using the little Radio Shack "high power" device well, is not a simple matter--the trick is to keep the eraser moving and using different angles and distances. If you want a high-power tape *degausser*, be prepared to part with some real cash--the low end seems to start just north of $1000. Many even claim to be able to do hard drives. --chuck
Re: Bulk tape eraser
You may as well run them through a shredder. All modern tapes have embedded servo tracks. On 4/30/17 7:38 AM, Mike Loewen via cctalk wrote: > >Looking for recommendations for a bulk tape eraser for SDLT and DLT IV > tapes. > > > Mike Loewenmloe...@cpumagic.scol.pa.us > Old Technologyhttp://q7.neurotica.com/Oldtech/
Re: Bulk tape eraser
On 04/30/2017 07:38 AM, Mike Loewen via cctalk wrote: > > Looking for recommendations for a bulk tape eraser for SDLT and DLT > IV tapes. If it's just a small quantity to be erased, there are many Radio Shack videotape erasers being offered, some NIB, all for about $20. I've used one for years on floppies and tapes. It's not for erasing piles of tapes, as there's a thermal overload protector on it, limiting the amount of time that you can use it. --Chuck
Re: Bulk tape eraser
I'd go to the Athana site, they have some degaussers and a nice write-up about what can (and can't) be safely degaussed 2017-04-30 11:38 GMT-03:00 Mike Loewen via cctalk : > >Looking for recommendations for a bulk tape eraser for SDLT and DLT IV > tapes. > > > Mike Loewen mloe...@cpumagic.scol.pa.us > Old Technology http://q7.neurotica.com/Oldtech/ >