Moderators: Dave Moll, Andrew Davie, Steve Anderson
Harry Dalek wrote:I do have 2 reel to reel recorders which i saved from here and there but yet to Test them ! as i get older i seem to have more time to try things out ..so another on the to do list i think i might be lacking a empty reel for the odd tapes i have to wind onto ..have to see if i ended up finding one or not .
Steve Anderson wrote:
Harry, I have a few empty 7" take-up spools for 1/4" tape, also one 5.5". If you really get stuck finding one I'll mail one to you...all have the 3-pronged "cine" hub arrangement, (the usual domestic tape-spool arrangement), not NAB. See pic..
Steve A.
Steve Anderson wrote:
Harry, I have a few empty 7" take-up spools for 1/4" tape, also one 5.5". If you really get stuck finding one I'll mail one to you...all have the 3-pronged "cine" hub arrangement, (the usual domestic tape-spool arrangement), not NAB. See pic..
Steve A.
Klaas Robers wrote:Wow Steve, you have a Philips tape spool. My heart opens....
Steve Anderson wrote:Harry, I have a few empty 7" take-up spools for 1/4" tape, also one 5.5". If you really get stuck finding one I'll mail one to you...all have the 3-pronged "cine" hub arrangement, (the usual domestic tape-spool arrangement), not NAB. See pic..
Steve A.
Klaas Robers wrote:The 400 Hz square wave LOOKS not too bad, however you lack a lot of high tones. This is not so strange, as for audio records the tones above 1.5 kHz are attenuated during play back. So the normal play back electronics, that you are usung, does this. This is called RIAA correction. Look at Wikipedia: https://en.wikipedia.org/wiki/RIAA_equalization and read about it. During recording a reverse correction is done. This is called pre-distortion.
This is because low tones are generally loud, so the lower frequencies have to be attenuated in order to limit the sideway excursions of the groove. And high tones are in audio less loud, so they can be boosted during recording without any harm. The advantage is then that they can be be attenuated during replay, which gives much less hissing noise of the disc survace.
This is all done and true for AUDIO. But for video the spectrum of low and high tones will be much different. Gramophone records are never optimized for NBTV video signals.
.AND we don't know how the frequency characteristic of your recording head is
How Baird did this, I don't know. However in his days home recording of gramophone records was more common (by hobbyists). Philips had a gramophone recorder on the market in those days, a machine as large as a washing machine, which recorded onto zinc discs, or at least discs with a surface layer of zinc. At least one person in the UK had such a machine and recorded on it a nightly BBC Television-broadcast. Don Mc Lean captured that disc and restored part of the video (without sound of course).
Klaas Robers wrote:...I am almost sure that the technicians at the BBC that built the VERA, encountered the same problems of starting and stopping and the occasional tape salad.
Steve Anderson wrote:I stand corrected, I said VERA ran at 120ips, it was actually 200ips or 5.08m/s, all these different machines amazingly close together in tape-to-head speed!
Steve A.
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