How to Record on the Wire

[dantheman321456987]

Hello,

I've built the heads as well as the track for the wire to run on. I have everything set up almost exactly like specified, and am using all the recomended materials/sizes etc. The only problem is that i can't record. I can hear a slight disturbance or feedback when i run the wire accross the head, but i only get a resistance of something small like 0.01 when i use the 20 ohm setting. I know it must be working since i am getting some sort of feedback, but i'm not sure how exactly to make it sound even remotely audible. I've even built four read/write heads, each with different numbers of coils. Any help or suggestions as to how to troubleshoot would be appreciated.

Thank you.

[rmarz]

dantheman321456987 - This is a very interesting experiment, but has a lot of potential for "issues". In your note, you say you followed the instructions "almost exactly". You might want to retrace where you may have altered something. There seem to be a few very critical elements. The first is the media, or steel wire you are using. Were you able to source a truly authentic, vintage wire suitable for recording/playback? The original media is only a few thousandths of an inch in diameter, often described as smaller than a human hair.

The second critical element is the fabrication of the recording head. The 'gap' is critical to the performance and should be as perfect as possible. I've never built a recording head, the suggestion of using a diamond wheel to cut it suggests the gap may be between 0.025-0.035 inches. I'm not in favor of the 'break the ferrite core and super-glue it together' method because you have introduced additional gaps in the head.

Another question relates to the resistance measurement you noted. Most simple multimeter have, as their lowest range, 0-200 ohms. You mentioned a 20 ohm range. In any case, I took the dimensions from the ferrite core suggested and it would say a single turn of #34 magnet wire is about 0.5 inches in length. For 340 turns, the wire length is about 180 inches. According to a copper wire table, #34 wire has a DC resistance of about 280 ohms/1000 feet. That suggests that your measurement should be about 50 ohms. Something is wrong with the coil, the meter or measurement technique.

Rick Marz

[dantheman321456987]

Hey rmarz,
Thank you for the advice, although i seem to have found the problem. I know that the recording wire i bought is in fact the right kind. It's diameter is only a few thou. As for the multimeter, i'm pretty sure i was measuring incorrectly, i probably had it on a wrong setting.

I think my gap may be a tad too wide. I was not able to get a diamond cutting wheel for my dremel, but i used a tool that gave me a gap about 0.050-0.065 inches thick. When i was running the recording wire over the outside of the gap, like is shown in the picture, i was getting no results. I changed the positioning of the bead so that it stood vertical but at a slight sideways angle, and i ran the wire through the gap, making it touch one edge on the top of the gap one one edge of the bottom part of the gap. Using this configuration, i was able to record a blurry series of "Hello"s across the wire.

thank you very much for your help
P.S just as a suggestion, maybe the page could be updated to specify around how big the gap should be, to make it a bit easier for others who decide to do this project.