Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Analogue Source Turntables, Tonearms, Cartridges, Phono Stages, Tuners, Tape Recorders, etc.

Wire recorder speed of wire
Wire recorder speed of wire
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 21st July 2019, 08:26 PM   #11
neazoi is offline neazoi  Greece
diyAudio Member
 
Join Date: Aug 2007
Quote:
Originally Posted by lcsaszar View Post
I would not modify that historical piece of equipment, provided it is in good working condition functionally and aesthetically. It must have a collector's value as is.
Oh no, I do not own one. I design one!
Here is a preliminary rough design of mine. It does not show the parts details so do not build it until I finish it and present it here. It is my idea and improvements over the original designs of wire recorders. Of course some things from the tape recorders have been borrowed and applied to the wire, like the capstan/spindle pair, to achieve constant speed.
The spools are not compatible with the vintage wire recorders, because my design aims on mechanical simplicity. Keeping the spools large in diameter, but with very little width for the wire to be wound, avoids the use of a complex "fishing reel" winding mechanism. Because of the spindle/capstan there is no speed change caused by the large diameter of spools. I use 0.4mm wire which is a bit thicker than the originals, but it is stronger and less prone to breaking. The large diameter spools would in theory hold quite a good amount of wire.
Fast forward function is provided and stretching of the wire is performed by reverse movement (but low torque) of the reels motors.
So you see how simple my design is?
Any comments are more than welcome!

So In that design I would like to investigate the effects of speed reduction combined with preemphasis of the high frequencies. Basically the previous questions in the previous posts (#8 and #9), just to find out more about the speed issues.
Attached Images
File Type: jpg Wire recorder V1.jpg (52.2 KB, 67 views)
__________________
Great DIY site: http://www.qrp.gr

Last edited by neazoi; 21st July 2019 at 08:31 PM.
  Reply With Quote
Old 21st July 2019, 10:04 PM   #12
PRR is online now PRR  United States
diyAudio Member
 
PRR's Avatar
 
Join Date: Jun 2003
Location: Maine USA
Look at a different form of writing. Liquid ink.

Ink on a tight-weave non-absorbent paper can write very small marks.

Ink on blotting paper, or paper towel, all marks spread-out, you can't write small.

Solid-metal "conducts" the magnetism, "spreads" it.

Rust media, the particles don't touch, small magnetic writing does not "blot" and spread so much.

You can't apply "infinite" EQ. The recording systems we know and use already have great heaps of many-pole high-boost. Any more gets trouble with record distortion or play hiss. This would be comparable to a smaller pen and sharper magnifying glass on the ink: at some point you just can't make/read any smaller.

Some, even much, "Stainless Steel" is mildly magnetic. The term covers MANY alloys. Some are actually "heat resisting" steel for boilers and turbines. There's SS which will stay bright in salt-air for decades, and SS which won't show much rust in soup-spoon use (short exposure to mild acid and occasional washing).

Yes, recording wire was "stainless". IIRC, it didn't rust like fence-wire, but with long damp storage it got lightly crusty. Here's a contemporary survey:
https://www.americanradiohistory.com...o-1953-Dec.pdf
15MB PDF, page 19 et seq

Recording wire is said to be 18/8 stainless steel, which apparently is a "cutlery grade" (so, soup-spoons).
Stainless steel - Wikipedia
"Ferritic and martensitic stainless steels are magnetic.
"Annealed austenitic stainless steels are non-magnetic. Work hardening can make cold-formed austenitic stainless steels slightly magnetic."

Last edited by PRR; 21st July 2019 at 10:09 PM.
  Reply With Quote
Old 21st July 2019, 10:47 PM   #13
neazoi is offline neazoi  Greece
diyAudio Member
 
Join Date: Aug 2007
Thanks a lot for the useful explanation and also about the article posted. I understand the problem with the speed you mention now and why was it operating at high speed.

I wonder how do you find my wire recorder idea?
__________________
Great DIY site: http://www.qrp.gr
  Reply With Quote
Old 22nd July 2019, 12:36 AM   #14
escksu is offline escksu
diyAudio Member
 
Join Date: Jun 2019
Quote:
Originally Posted by eduard View Post
Hello,
Unless it is 430 stainless steel stainless steel will be not magnetic.
Greetings, Eduard

Oh ok. Thanks for pointing it out to me!! Thanks!!!
  Reply With Quote
Old 22nd July 2019, 01:28 AM   #15
JMFahey is offline JMFahey  Argentina
diyAudio Member
 
JMFahey's Avatar
 
Join Date: Mar 2009
Location: Buenos Aires - Argentina
Quote:
Originally Posted by neazoi View Post
Well if the high frequency response is the reason for the high speed, why couldn't we use an emphasis of the highs during recording so that the audio response curve is equalized, without the need for high speed? Dolby on tapes does a very similar thing, but back on the wire days there was no dolby probably.
When recorded wavelength becomes comparable to recording "window" width it starts erasing itself.
EQ cannot help you with what´s not there to begin with.

Same way as no amount of EQ will turn a 1" "woofer" into a PA type one.
__________________
Design/make/service musical stuff in Buenos Aires, Argentina, since 1969.
  Reply With Quote
Old 22nd July 2019, 06:03 AM   #16
PRR is online now PRR  United States
diyAudio Member
 
PRR's Avatar
 
Join Date: Jun 2003
Location: Maine USA
Historical papers:
AUDIO - Consumer audio and music magazine from 1947 to 2000.
Nov '47, Dec '47, Jan '48
ELECTRONICS: Electronics Engineering magazine beginning in 1930
Jul '45
  Reply With Quote
Old 29th July 2019, 12:52 AM   #17
neazoi is offline neazoi  Greece
diyAudio Member
 
Join Date: Aug 2007
Quote:
Originally Posted by PRR View Post
Hi again,
The head used to be a toroid with a gap at one end and onto the toroid the wire was wound. The toroid then becomes an electromagnet with changing magnetic field intensity, depended on the signal fed into it.

A problem with the wire recorders is referenced on wikipedia:

"Poulsen's original telegraphone and other very early recorders placed the two poles of the record/replay head on opposite sides of the wire. The wire is thus magnetised transversely to the direction of travel. This method of magnetization was quickly found to have the limitation that as the wire twisted during playback, there were times when the magnetization of the wire was at right angles to the position of the two poles of the head and the output from the head fell to almost zero. The development was to place the two poles on the same side of the wire so that the wire was magnetised along its length or longitudinally. Additionally, the poles were shaped into a "V" so that the head wrapped around the wire to some extent. This increased the magnetising effect and also increased the sensitivity of the head on replay because it collected more of the magnetic flux from the wire. This system was not entirely immune to twisting but the effects were far less marked. The longitudinal method survives into magnetic tape recording to this day. "

So now I wonder, if I can wrap a solenoid around a plastic former and pass the wire through the coil. The solenoid should magnetize the wire with the longitudinal method, as the wire itself will become the "core" of the electromagnet. And this should eliminate the twisting problem mentioned above, as the wire would be magnetized all the way around.

I have seen this technique applied in a thin rope covered with magnetic particles, Wire Recorders - Museum of Magnetic Sound Recording see this http://museumofmagneticsoundrecordin...rlinSmith2.jpg

Will this work?
__________________
Great DIY site: http://www.qrp.gr
  Reply With Quote
Old 29th July 2019, 04:50 AM   #18
PRR is online now PRR  United States
diyAudio Member
 
PRR's Avatar
 
Join Date: Jun 2003
Location: Maine USA
> wrap a solenoid around a plastic former and pass the wire through the coil

Sounds like the equivalent of a very long "gap". Mildly wasteful for record. Very-very limiting of highs on playback. Encourages high wire speeds, and I thought you wanted lower speed?

But if you have a working transport, it is a cheap experiment.
  Reply With Quote
Old 30th July 2019, 09:02 PM   #19
Mark Tillotson is offline Mark Tillotson
diyAudio Member
 
Join Date: May 2018
Location: Cambridge UK
Quote:
Originally Posted by neazoi View Post
Hi, I want to find out why wire recorders worked at that high wire speed?

Because the medium is huge, hundreds of microns across, limiting the bandwidth. Magnetic tape active layer can be a few microns, hard disk media much thinner still.


Its pure geometry, different parts of the signal must not overlap in space. hard drive technology has taken the art to extremes, using sophisticated multi-layer materials and vertical magnetic flux focussing using a backing layer. This is how you get 10^12 bits per square inch or whatever the record is now.

Last edited by Mark Tillotson; 30th July 2019 at 09:05 PM.
  Reply With Quote

Reply


Wire recorder speed of wireHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
FS: Sjostrom Diamond Buffers / Wire LT1763 / Wire HP amp kits passive420 Swap Meet 4 30th April 2016 02:40 AM
Signal leads for balanced miniDSP - 3-wire vs. 2-wire+outer braid Pallas miniDSP 2 18th April 2012 02:16 PM
Litz Wire for audio applications (18AWG, New England Wire Type 2) Chook81 Vendor's Bazaar 2 24th January 2012 08:32 PM
22 AWG silver plated solid copper wire for speaker wire? G Full Range 21 15th February 2009 09:32 PM
wire speed lopan Everything Else 10 11th January 2005 11:58 PM


New To Site? Need Help?

All times are GMT. The time now is 09:27 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki