Moderators: Dave Moll, Andrew Davie, Steve Anderson
smeezekitty wrote:Seems like it is being swamped by the low frequencies. Might try high-pass filtering the signal before you record it
Viewmaster wrote:My God Harry, you are a glutton for punishment !
If you use a speaker to cut grooves it must be damped I found.
I used a rubber pad for the speaker to drive into, to offer some resistance,
not free running as it were.
Looks like you are lateral cutting, Harry.
Edison and I ( ) used hill and dale cutting.
Either way, there is a very delicate balance between over and under modulation.
Too much under and the noise level goes up on playback.
Too much over and one groove runs in to the next.
I always examined my grooves under a microscope to see if the
modulation was OK and this also told me
what the highest frequency was being recorded.
Good luck. I spent a few years developing mine......
Trial and error. Trail and error......mostly error
Viewmaster wrote:Harry, I'm not sure how you are going to get sync.?
If you can record the standard NBTV sync signals we normally use
together with the video signal you are home and dry.
But I could not record reliable signals on wax so I developed an external syncing signal.
I arranged for exactly 3 frames per rev of wax cylinder to be recorded.
I could then mechanically generate 3 sync signals per rev on playback.
The radial position of these was movable around the wax cylinder
on playback to get the correct sync point.
BTW it was either Steve (Anderson)_ or Gary who told me to damp
the loudspeaker.
They were both very helpful to me during my struggles.
I do hope that you succeed in your endeavours, Harry.
I shall be watching you from afar.
Klaas Robers wrote:You do not need a needle for recording, you need a chisel, a very small chisel that cuts the material and forms a fine and well defined groove.
There is coming out material, that you should remove from the surface during recording. If you look at the book cover of "de mannen van de hobbyclub" you see one with a fine brush on the disc under recording. He is removing the cut out material. I have seen long ago the recording of a 33 1/3 rpm long playing record. There a very small vacume cleaner pics up the material directly after the chisel. So no pinsel.
And the loudspeaker, you can hear the distorted sound during recording. That is also more or less, what is recorded. That sound should be fine and undistorted, and even then yoiu are unsure how the play back sound will be. You hope that it is getting better, but in reality it is always getting worse. "Rubbish in, rubbish out" is a general rule that is always aplicable. Sorry.
Klaas Robers wrote:Harry, the title page of the book "De jongens van de Hobbyclub" (translated: The Boys of the Hobbyclub") is just a few posts up in this thread. It is a post of yours. You might not be able to read Dutch, but you can look at the nice picture.
However, reading of Dutch is not SO difficult. Read it aloud and listen to your own voice. Do not go too fast.
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