My TDK Cassettes Collection

yeah getting one from ebay is easy if you want to spend top dollar, i'm tempted to get a Maverick of the bay...but the original Audua is rare as it is and i found one that meets my criteria, tabs intact, clean j-card and preferrably with clean sticker sheet. And the nice thing about buying used cassettes is that there is music on them or that i never heard of, or it's something i like so then i will keep it....have some nice Jimi cassettes now, also an album by Talk Talk that i didn't had.
If i don''t like the recording they will go through the Weircliffe bulk eraser and the tape is fresh again. And since i also buy bulk cassette lots, all the doubles i have will go on sale so i can buy some more TDK that i don't yet have.
And will have to see if to Ikea frames are still available, maybe some will turn up in the thriftstores here....

 

Interesting device, this weircliffe - how does it work ? Only putting the cassette in the slot, and push the button ? I can`t imagine, that really the whole tape is erased completely.

 

well this Weircliffe Model 6 was a standard device that you could find in pro recording studios back in the 60's, 70's, 80's and still used today by me and was designed to erase reel to reel tape, in this model 6 inch tape are the max....there is also a Model 8 and even a model 10 or 12........
But bying new tape back then was to expensive so to degauss it they had a bulk tape eraser like the Weircliffe.
As you might know when you put current on a transformer coil (or any copper coil) a magnetic field is created within the center of the trafo coil, this is the way solenoids work for example.
So this magnet, which in this device measures approx 30cm x 25cm, which is huge, is then cut in half to release the magnetic field and you have a bulk tape eraser. You can even build yourself one, search on google for diy bulk tape eraser but be aware you're working with LETHAL voltages!
So this magnetic field randomizes all the ferro/chrome/metal particles on the tape to zero/bias state which basicly means you have new tape.
No more shadow copies to be heard what sometimes happens when you record over an old recording and the deck you recorded on has not enough Gauss to erase the tape.
For example take this page http://vintagecassettes.com/tdk/tdk_files/tdk_type/tdk_ma.htm
TDK MA
Magnetic Particle: Finavix

Coercivity: 1130 Oe
Remanence: 3200 Gauss
Squareness Ratio: 0.84

You can see coercivity is 1130 Oersted and remanence is 3200 Gauss (which is high), if the current of the erase head isn't high enough the tape will ot be fully erased.
This Weircliffe easily erases ferro,chrome and metal cassettes. Also has no problem fully erasing DAT tapes, wipes them totally clean including all indexes....
But read this on wikipedia
Degaussing, or deperming, is the process of decreasing or eliminating a remnant magnetic field. It is named after the gauss, a unit of magnetism, which in turn was named after Carl Friedrich Gauss. Due to magnetic hysteresis, it is generally not possible to reduce a magnetic field completely to zero, so degaussing typically induces a very small "known" field referred to as bias. Degaussing was originally applied to reduce ships' magnetic signatures during World War II. Degaussing is also used to reduce magnetic fields in tape recorders and cathode-ray tube displays, and to destroy data held on magnetic storage.

and...

Data is stored in the magnetic media, such as hard drives, floppy disks, and magnetic tape, by making very small areas called magnetic domains change their magnetic alignment to be in the direction of an applied magnetic field. This phenomenon occurs in much the same way a compass needle points in the direction of the Earth's magnetic field. Degaussing, commonly called erasure, leaves the domains in random patterns with no preference to orientation, thereby rendering previous data unrecoverable. There are some domains whose magnetic alignment is not randomized after degaussing. The information these domains represent is commonly called magnetic remanence or remanent magnetization. Proper degaussing will ensure there is insufficient magnetic remanence to reconstruct the data.[7]

Erasure via degaussing may be accomplished in two ways: in AC erasure, the medium is degaussed by applying an alternating field that is reduced in amplitude over time from an initial high value (i.e., AC powered); in DC erasure, the medium is saturated by applying a unidirectional field (i.e., DC powered or by employing a permanent magnet). A degausser is a device that can generate a magnetic field for degaussing magnetic storage media.[8] The magnetic field needed for degaussing magnetic data storage media is a powerful one that normal magnets cannot easily achieve and maintain.[9][10]


So yes it completly erases all data that is on any magnetic layer....on the Weircliffe is a warning that people who have a pacemaker cant use this machine...also bank cards and wrist watches need to stay far away or they will be damaged.....

And ofcourse i check every cassette after ive put them through the eraser if it was properly erased. Basicly you press the the slot cover down, this activates the trafo, slide your cassette in en out and it is done...like 5 seconds work....metal tapes like MA take two slides and need to be exposed a bit longer then ferro tape......
Last few weeks ive succesfully degaussed more then 300 cassettes all ready for new recordings.

Does this help?

 

Very detailed explanation - thank you. I only had the basic knowledge. It`s not easy to get one with the europian 230 V - standard.

 

yeah i was looking for one for many years. They do popup on ebay but shipping from US or AUS is not viable (thing weighs about 25-30kg) and those run on 110V....
but i was lucky to find one in NL only 45 minutes drive from my house. It came from an estate clearance.
And Weircliffe is/was an English company so that i have an 'export 220V' one is special.