Quote:
Originally Posted by ppppenguin
Recovering A format tapes is tricky. The basic video track geometry is identical to C format but there are all sorts of other differences. Many years ago I got pictures from an A format PAL tape (recorded on a VR7003) by playing it on a C format machine. All sorts of things were wrong but I believe then and still believe now that it would be possible to modify a C format machine to do the job well.
AFAIK there are no working or readily restorable A format machines in UK/Europe. There are a number of working C format machines in private hands. There may be a very few working A format machines in the USA. The NTSC versions of A format will not play PAL tapes and vice versa. C format machines may be dual standard but I'm not certain.
From my own recollections, the Memorex A format tape was very abrasive compared to other makes. I tried to avoid using it.
Conclcusion: You will be very lucky indeed to recover matarial from these tapes.
PS: There's the possibility that these tapes don't contain video at all. I thinkk that A format machines were sometimes used by NASA and others to record data. At the time, VTRs were about the widest bandwidth recording devices in existence. They did this by dressing it up as video. Digital audio was recorded like this on Umatic and Betamax (PCM-F1) machines at one time.
PPS: There's a possibility that these are IVC 700/800 series tapes. ISTR the spools are slightly smaller diameter than A format. I don't have experience of these machines but there maybe working examples.
|
Thanks for your thorough reply Penguin.
I will be able to share much more when the tapes arrive. I got my own magnetic viewing solution, so will be able to share photos of the tracks.
How long would one video frame be on a length of tape? I assume it would be preferred to view one entire frame. I can always do a piece in sections and stitch the photos in post.
Would it be possible to determine PAL or NTSC from the visualization of the tracks? What resolution would be required? I assume from the amount of helical scan lines between two edit/frame points?
When you played a type A tape in a type C machine, did you get any audio?
Even if I can't find a type A machine locally, it may be a good idea to try playback on a newer machine as long as I can get audio. Then I can determine by that if it is NASA/Apollo related or something else... like I Love Lucy!
Baking would probably be required to have any hopes of clean playback...
Regards,