Barry777
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Jul 18, 2010, 3:46 PM
Post #69 of 98
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I think at this point, all you have is a few minor mechanical quirks which can probably be fixed by simply playing around with the machine some more, and letting it cycle a bunch of times. The mechanism is probably sluggish from not being used in years, and should get smoother each time you go into the various modes. I'd give the machine a 5 minute break every 10 cycles though, just to be safe and keep the loading motor from overheating.
I wouldn't worry about the counter running in reverse; you'll notice that there is a negative sign when it appears to be running in the wrong direction in relation to the tape - must be some kind of thing with the editing function. These pro machines have so darn many functions and features, they take a while to figure out. Your tape will also run forwards and/or backwards for a few seconds before the machine is ready to actually use - it's part of the preroll function, and ensures that the picture will be stable at times when it otherwise might not be on a lesser machine.
Fault 71 is the capstan, 72 is the supply reel and 73 is the takeup reel. Since you don't always get the same code, that's a very good sign the mechanism is okay and just needs to be smoothed out, maybe lubricated. The actual wording of the codes is "motor failure", but all it means is that it's not sensing the proper action - I'm sure the motors are fine. A sluggish or balky mechanism can make the motors appear defective to the CPU. I'd say just keep messing with it and don't take anything apart yet.
How does it do going into PLAY mode? Do the guide posts act quickly and smoothly wrapping the tape around the drum? Does the mechanism appear to strain or stall during any of the functions? The squealing noise suggests that it's hanging up somewhere and it might need a lube job. This would likely explain the fault codes, as even a momentary stall can activate the fault condition and prevent further operation. Recycling the power will reset the machine for another try.
I think you'll have the whole machine running properly today - and this is a further testimonial to my favorite VCR repair axiom: It's probably something simple. But it sure sounded like multiple electronic failures when you first tried it! Incidentally, you can get a new pinch roller for this unit if it appears cracked or slippery - it's part number PR-14 at www.studiosoundelectronics.com It's only about $6, so I replaced all of mine, what the heck. Thankfully my BR-S800's and S500's have the same mechanism anduse the same roller. I have an easier way to replace it than the procedure in the manual also.
Even after then mechanism clears up, I would plan on giving it a lube job fairly soon, to prevent too much wear on the loading cam (that large round gear with the snakelike channel), as this would be an impossible part to find. I'm pretty sure you can lubricate that channel from above. In fact, there's very little under the mechanism so you shouldn't need to pull it. That's another nice thing about JVC pro machines - very easy to servce. The only reason I really HAD to pull the transport was to replace that surface mount cap on the drum stator board to restore the PG pulse and get my servos back in sync.
I've found a syringe filled with lithium grease to be the best way to lubricate a VCR - you can pump a small plug of that stuff right into that loading cam channel, without getting it anywhere you don't want it to go. Another little shot where any gears mesh, and a thin coat along the guide post channels. To get at the underside of those channels, simply use a Q Tip and apply some to the sides with an upward motion - this will deposit the lubricant underneath, then the guide posts will spread it when they do their thing in PLAY mode. Easy and cheap insurace against excessive wear.
I finally started copying my lengthy editorials just in case. Though it's a simply, cheesy program with few features, I've been using WordPad as long as I can remember - since it's guaranteed to be on any computer I run into. You know me, the passionate lover of "easy and simple"!
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Barry Fone - VCR Repair hobbyist and professional FAA Repair Station Avionics Bench Technician (top level). TEST EQUIPMENT: (4) Sencore VC93 VCR Analyzers, (11) Tentel gauges, Sencore VA48 and (2) VA62 Video Analyzers, Sigma Electronics TSG-375 NTSC/SMPTE Video Generator, several VCR Alignment Tapes, plus countless Oscilloscopes, Frequency Counters, Wow and Flutter Meters, Distortion Analyzers, Vectorscope, 136-channel Logic Analyzer, Signature Analyzer . . . . VIDEO GEAR: (6) JVC BR-S822U's, (3) JVC BR-7000 series, (3) JVC BR-S500U, (2) JVC BR-S800U, JVC GR-800U and (2) GR-860U Editing Controllers, Sony FXE-100 Video Switcher/Effects Generator, (5) Time Code Generator/Readers, (1) Sony SLO-1800 (Beta), (2) Alesis ADAT-XT, (1) Sony DXC-1200 TV Camera, Pioneer VP-1000 Laser Disc Player plus many consumer grade Beta and VHS VCR's. Passionate electronics enthusiast since 1973...most anything except computers. Check out my collection at www.barrys8trackrepair.com/MyVideoGear.html
(This post was edited by Barry777 on Jul 18, 2010, 4:23 PM)
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