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Old 06-19-2010, 07:22 PM
Barry777 Barry777 is offline
Avionics Technician
 
Join Date: Jun 2010
Posts: 45
Hi Ed,

These machines do have adjustable video record level as an option, along with seemingly hundreds of menu-driven adjustments I dare not mess with for lack of knowledge of what they do! I hadn't considered recording on the bad one and seeing how it plays on another machine, thanks very much for the tip. I'll also study the service manual for more clues - too bad I can't twirl my hand fast and accurately enough to inject a head signal into that large SMT chip on the spinning board. I have one of those cheap handheld video head testers, but of course they won't identify a clogged head. Well, maybe I can look for a dramatic change in inductance between the heads just for fun. I also haven't tried a dry type cleaning tape, and I might just have one around.

A machine of that age could definitely have bad electrolytics pretty much anywhere; in fact I stole the audio output board from the bad machine over this. I stock hundreds (or thousands) of all standard values up to 1000 uF, but generally don't keep many NP's around which were the culprits in this case. I could get really intense and try measuring in-circuit capacitance of the SMT caps, but I'm more likely to just replace them once I determine the values. I'll try to shoot you a protrusion measurement in microns on these heads if I can find time over the weekend, but a quick and gentle finger-rub feels like well over 20 microns on all of them. I had pretty much written the machine off as a parts unit, but here's my chance to really make sure it's the heads, and learn a lot besides.

Considering the way these machines performed after routine mechanism removal, cleaning and lube, looks like the previous owner(s) kept up the maintenance and alignments very diligently. Almost a disappointment for a curious technician, but at least I have some Beta machines to mechanically align and keep any hair from accumulating on my head!

Thanks again for the tips, I'll keep you posted. Cheers!

P.S. - If I keep getting older, I may need to project scope waves on my wall too! My wife is an old California hippie, so the process is sort of pre-approved if I play some Iron Butterfly while I troubleshoot.

Last edited by Barry777; 06-19-2010 at 07:27 PM.
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