[sci.electronics] Magnetic Wire Recorders

adams@swbatl.sbc.com (Tom Adams - 235-7459) (07/14/90)

I'm looking for information about magnetic wire recorders.
I'm also curious about the history of this technology.

Is anyone aware of any controversy on the subject?
The National Inventors Hall of Fame apparently credits Marvin Camras
with inventing wire recorders in the 1930's, while "Magnetic Recording",
by S.J. Begun, 1949, Rhinehart, credits Vladimir Poulsen with inventing
a wire recorder called the Telegraphone in the late 1890's [!]. 
I'd also be very interested in hearing from folks who have wire
recorders (or want to get rid of one) or pointers to more books and
articles.  The Begun book has bibliography I'll share with anyone
interested.

Thanks
-- 
uunet!swbatl!adams or adams@swbatl.sbc.com     
Tom Adams: 314-235-7459: Southwestern Bell Telephone Advanced Technology Lab
BOOKS WANTED: pre-1930 radio, electrical & scientific topics

mmm@cup.portal.com (Mark Robert Thorson) (07/14/90)

During WW2, my dad worked in naval intelligence searching for Japanese subs
by listening for their radio transmissions.  They'd use direction finders
to get a vector to the transmitter, and triangulation among multiple
listening posts to find the location.

This work was made more difficult by the wire recorders used by the
Japanese.  They'd record a message in something like Morse code, then
play it back in a high-speed burst for transmission.

larry@kitty.UUCP (Larry Lippman) (07/15/90)

In article <1990Jul14.044030.6001@swbatl.sbc.com>, adams@swbatl.sbc.com (Tom Adams - 235-7459) writes:
> I'm looking for information about magnetic wire recorders.
> I'm also curious about the history of this technology.
> 
> Is anyone aware of any controversy on the subject?
> The National Inventors Hall of Fame apparently credits Marvin Camras
> with inventing wire recorders in the 1930's, while "Magnetic Recording",
> by S.J. Begun, 1949, Rhinehart, credits Vladimir Poulsen with inventing
> a wire recorder called the Telegraphone in the late 1890's [!]. 

	There were *several* people working with magnetic recording
technology before 1900.

	Waldemar Poulson, a Danish electrical engineer, is generally
credited with the invention of wire recording during the mid-1890's.  His
invention has been referred to by various [now archaic] names, such as:
telephonograph, microphonograph, magnetophonograph and telegraphophone.
I don't know of any controversy with respect to giving Poulson credit
where credit is due for this invention.

	Poulson's device employed hardened steel piano wire of a diameter
around 0.040 inch which was wound around a cylinder about a foot long.
The overall appearance of his device is similar to that of a cylinder
phonograph.  In Poulson's original design something like 200 turns of
wire were used, providing somewhat less than one minute of recording time.

	Poulson and others made various design improvements to increase
recording time and sound quality.  One variation which emerged was
referred to as the "band microphonograph", and employed two reels which
used a steel band approximately 0.3 inches wide by 0.087 inches thick.
The magnetic pickup/recording head was fixed.  This device could provide
over one hour of recording time.

	There were various bizarre schemes proposed during the 1890's
which used this technology.  One was called the "Talking Newspaper",
and involved distributing a daily newspaper via wire recording.  I
believe it was actually tried on a small scale in Europe. 

	Magnetic recording technology did not come into serious use until
after World War I when vacuum tube amplifiers were well established.  While
the devices produced by Poulson and others did in fact work, their sound
recording and reproduction ability was seriously hampered by the lack of
amplification. 

	For the most authoritative and reliable information on this topic,
one should consult books written between 1895 and 1915.  A good example
from my personal collection is "Electricity in Every-Day Life", a 3-volume
set written by Edwin J. Houston, PhD and published in 1905 by Collier & Son.
The title is rather misleading in that these volumes contain 1700+ pages
with a wealth of specific technical detail, and were not intended for the
lay person.  There are profusely illustrated with drawings, photographs
and color plates.

Larry Lippman @ Recognition Research Corp.  "Have you hugged your cat today?"
     {boulder||decvax||rutgers||watmath}!acsu.buffalo.edu!kitty!larry
VOICE: 716/688-1231 || FAX: 716/741-9635  {utzoo||uunet}!/      \aerion!larry

kimf@arrester.caltech.edu (Kim Dorian Flowers) (07/17/90)

What were the main disadvantages of wire recorders as compared
cassette tape-types?

Kim Flowers
kimf@tybalt.caltech.edU

ee5391aa@hydra.unm.edu (Duke McMullan n5gax) (07/19/90)

In article <kimf.648180192@arrester> kimf@arrester.caltech.edu (Kim Dorian
Flowers) writes:
>What were the main disadvantages of wire recorders as compared
>cassette tape-types?

The one problem of which I'm certain was that the wire tended to wear a DEEP
grove in the head.

Here'a a thought: You've probably spliced recording tape. Now, try it with a
ferromagnetic wire....


Wire you asking about this?


						d


--
			"Peace is hell." -- Skyler
   Duke McMullan n5gax nss13429r phon505-255-4642 ee5391aa@hydra.unm.edu

bill@bilver.UUCP (Bill Vermillion) (07/20/90)

In article <1990Jul14.044030.6001@swbatl.sbc.com> adams@swbatl.sbc.com (Tom Adams - 235-7459) writes:
>I'm looking for information about magnetic wire recorders.
>I'm also curious about the history of this technology.
>
>Is anyone aware of any controversy on the subject?

No controversy - just a pain.

My first recorder was a Webster Chicago unit.  (I went to retreive it several
years ago and found my mother had given it away - argh!).

Wire was able to store more recording in a given space with higher quality
than competing tape technology.   A 1 hour spool was about 2.5 inches across
and 1" high.

The problems were if you dropped it, or it came unspooled.  Ever see a fishing
reel that got tangled.  Picture the same mess with very fine stainless wire.

Splicing was a pain.  I was in the studio one day years ago when another
studio engineer said wire's main problem was you couldn't edit it.

I said to him " Gee, I wish I'd had know that years ago before I edited all
those wires.  I wouldn't have tried it."

To edit (more like assemble) you tie the wire in a square knot and trim the
ends with a scissors.   They pop going across the head.

The bigger problem is that the wire will twist axially, and it will not be
presented to the record/play head in the same orientation as it was recorded.
Because of this the highest frequencies aren't always retreived properly.

However it was better in the late '40's than the competing tapes.

In about 1961, when I was working at KXLY in Spokane WA, we came across a
couple of reels of tape for the Brush SoundMirror.   These tapes were
originally shipped on 8mm film reels.   They were paper tape with a black
oxide coating.   We adjusted one of our Ampex 350's to be flat out to 15k for
the tape we were using , probably 111 at that time.   

We then tried the old tape.  Best we could get out of it was a little over 5k.
I don't remember whethere that was 7.5ips or 15 ips at that time.  

The rule of thumb in the mid-50's was 1kHz (but in those days we called it
cps!) per 1"/sec of tape speed.  Many early recording were done at 30 ips to
get extended response.  When the NAB curves were introduced, 15 ips became the
standard mastering speed.

Wire was used quite extensively before tape was perfected.   I remember
working at my first radio job in 1958, and the transmitter site had several
spools of military surplus wire.  Whether these dated to the war years, or
just from the late 40's I don't know.

Wire was good for it's day.  The only medium that was competing on noise and
quality was metal tape.  Not metal tape as we know it today, being metal on a
plastic carrier, but metal strips.  Imagine a VERY long measuring tape.
Imagine a very heavy turntable supporting the tapes.  Imagine more than 100
pounds to record an hour.  

>The National Inventors Hall of Fame apparently credits Marvin Camras
>with inventing wire recorders in the 1930's, while "Magnetic Recording",
>by S.J. Begun, 1949, Rhinehart, credits Vladimir Poulsen with inventing
>a wire recorder called the Telegraphone in the late 1890's [!]. 
>I'd also be very interested in hearing from folks who have wire
>recorders (or want to get rid of one) or pointers to more books and
>articles.  The Begun book has bibliography I'll share with anyone
>interested.

Camras just wrote another book about 2 years ago called "Magnetic Recording" -
and if you want to know ANYTHING at all regarding Magnetic recording that's
the book to get.  Aboug $85.00.  Addison Wesley if I remember.

Camras was also instrumental in developing the accicular magnetic particles
for tape while he was working at either Armour Research or 3M.  That is the
type of coating still in use today.



-- 
Bill Vermillion - UUCP: uunet!tarpit!bilver!bill
                      : bill@bilver.UUCP

bill@bilver.UUCP (Bill Vermillion) (07/23/90)

In article <1990Jul18.170150.29014@ariel.unm.edu> ee5391aa@hydra.unm.edu (Duke McMullan n5gax) writes:
>In article <kimf.648180192@arrester> kimf@arrester.caltech.edu (Kim Dorian
>Flowers) writes:
>>What were the main disadvantages of wire recorders as compared
>>cassette tape-types?
>
>The one problem of which I'm certain was that the wire tended to wear a DEEP
>grove in the head.

The head STARTED with a deep groove to carry the wire.   It did not seem to
accelerate wear after that point.  The stainless wire is MUCH smoother than
the ferric oxide for tape heads.

There were some older models of wire recorders in which you threaded the
recording wire through a hole.  No wear to speak of in those.

Wear was a problem even in tape in those days.  Head material was very soft.
We kept spare pole pieces for a Magencord PT6's around for quick replacement.
The poles were only about $15, and looked almost like a bunch of staples
soldered together sideways.    You just undid the screws that held the top of
the head case on, lifted the pole pieces out, and put a new set in.  Probably
good for about 500 hours, but we never timed them.  When you could see the gap
easily, you just changed the pole pieces.


>Here'a a thought: You've probably spliced recording tape. Now, try it with a
>ferromagnetic wire....

You just tie it in a square knot, and clip the ends.   You can splice, you can
assemble, but you just can't edit.  I did it a lot when in high-school.

Of course if you had one of the hole type heads mentioned above, this wouldn't
work, as the knot wouldn't pass throught the hole.

And speaking of splicing, I used to help make dubs in the Radio-TV department
at college.   We would send out tapes to all the stations in the state each
week, and then redub the next week.   We saw tapes spliced together with
everything you could imagine.  One of the strangest was the one that was
"spliced" with a 3-cent postage stamp.

bill


-- 
Bill Vermillion - UUCP: uunet!tarpit!bilver!bill
                      : bill@bilver.UUCP

alz@tc.fluke.COM (Al Weiss) (07/26/90)

Is my memory playing tricks with me or do I recall correctly that wire
recorders have been used in satellites? Would someone elaborate on that
usage?

Al
-- 


-----------------------------------------------------------------------------
Al Weiss                   alz@tc.fluke.com                      206-356-5252
John Fluke Mfg. Co., Inc.  MS-269E   PO Box 9090  Everett, WA 98206-9090  USA

witters@tc.fluke.COM (John Witters) (07/26/90)

In article <1990Jul25.184953.7175@tc.fluke.COM> alz@tc.fluke.COM (Al Weiss) writes:
>Is my memory playing tricks with me or do I recall correctly that wire
>recorders have been used in satellites? Would someone elaborate on that
>usage?

The technology is called plated wire.  I think it is used for computer memory
in a way analogous to old fashioned ferrite core memory.  I know nothing more
about it except that it is more resistant to radiation than semiconductor
memory.  Radiation from the sun is something you have to worry about when you
put something outside the atmosphere.

Would anyone from NASA care to comment?

-John
-- 
    *  *  *		John Witters			voice:	(206) 356-5274
  *  \      *		John Fluke Mfg. Co. Inc.
 *    \      *		P.O.B. C9090 M/S 245F		fax:	(206) 356-5116
*   DRIVING   *		Everett, Washington  98206	     or (206) 356-5174
 *      \    *
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    *  *  *		uucp:	{sun,microsoft,uw-beaver}!fluke!witters

henry@zoo.toronto.edu (Henry Spencer) (07/26/90)

In article <1990Jul25.203604.1577@tc.fluke.COM> witters@tc.fluke.COM (John Witters) writes:
>>Is my memory playing tricks with me or do I recall correctly that wire
>>recorders have been used in satellites? ...
>
>The technology is called plated wire.  I think it is used for computer memory
>in a way analogous to old fashioned ferrite core memory...

It's fairly similar to core memory, using coatings plated on a wire matrix
rather than little ferrite doughnuts strung on the matrix.  It has nothing
to do with wire recorders; the wire in plated-wire memory does not move.
-- 
NFS:  all the nice semantics of MSDOS, | Henry Spencer at U of Toronto Zoology
and its performance and security too.  |  henry@zoo.toronto.edu   utzoo!henry

iws@sgfb.ssd.ray.com (Ihor W. Slabicky) (08/02/90)

In article <828@bilver.UUCP>, bill@bilver.UUCP (Bill Vermillion) writes:
> 
> And speaking of splicing, I used to help make dubs in the Radio-TV department
> at college.   We would send out tapes to all the stations in the state each
> week, and then redub the next week.   We saw tapes spliced together with
> everything you could imagine.  One of the strangest was the one that was
> "spliced" with a 3-cent postage stamp.


Sure :-) but did it work?!?!

crs@lanl.gov (Charlie Sorsby) (08/03/90)

Just a point of information:  I believe that stainless steel is
non (or at least not very) magnetic.  I think the wire used was
probably not stainless, but I've been wrong before...

Best,

Charlie Sorsby						"I'm the NRA!"
	crs@lambda.lanl.gov
	sorsby@pprg.unm.edu
-- 
Charlie Sorsby
			crs@lambda.lanl.gov
			crs@agps.lanl.gov