1987 Magnavox (rebadged Panasonic) VCR Malfunction

[Captainclock]

Hi Everyone, I had just bought the other day at the local Goodwill for $15 a 1987 Magnavox Stereo HiFi VCR Model VR9670AT01 (which is quite obviously a rebadged Panasonic VCR). I like to keep a few spare VCRs around because I still have a lot of VHS tapes around and some of them are titles that have yet to be re-released to DVD so VHS is the only way to watch them.

Anyways when I got it home to plug it in and power it up, nothing, it was completely dead, no display, no power-up test nothing.
So I opened it up to check the fuses and none of the fuses were blown (I checked the main power supply fuse, and a secondary power supply that apparently powers the loading mechanism and I checked the fuse for that and it wasn't blown either), I also checked all of the circuit boards for any obvious signs of electrical burns/damage and nothing, it was as clean as a whistle inside not even a speck of dust could be found inside the VCR.

Although one thing that stuck out like a sore thumb was that the metal cover that covered the undercarriage of the VCR had signs of water damage but yet the circuit boards underneath were clean no signs of water damage, same for the rest of the VCR.
So now my big question is, how do you have a completely dead VCR without any blown fuses, no electrically damaged circuit boards and no signs of water damage on the VCR except on the bottom cover?
This is really got me stumped because this is probably the cleanest VCR I've ever worked on and yet it doesn't seem to want to power up...

Any ideas as to what the problem could be?
Or has anyone else had the same problem in the past that could share some repair tips or advice?

Any Help would be appreciated.

[Electronic M]

If it uses a Switch Mode Power Supply instead of a power transformer then it can die without blowing a fuse. Caps, diodes, and transistors can fail in a SWMPS and still look perfectly fine.

BTW if you want a really good preforming VCR look for S-VHS decks those can play VHS tapes with much better picture quality than run of the mill VHS units.

[Captainclock]

Originally Posted by Electronic M

If it uses a Switch Mode Power Supply instead of a power transformer then it can die without blowing a fuse. Caps, diodes, and transistors can fail in a SWMPS and still look perfectly fine.

BTW if you want a really good preforming VCR look for S-VHS decks those can play VHS tapes with much better picture quality than run of the mill VHS units.

I did have a JVC S-VHS unit for a while that I picked up at a yard sale that was held at the home of a collector of vintage electronics for $10 but it didn't have its original remote so it was practically useless because the only functions that worked without the remote were the play, F. Forward, Rewind and Stop/Eject functions the rest of the functions (tape counter, OSD etc.) had to have the original remote for them to work.
To get a replacement remote at some place like eBay or Parts Express would of been well over $100 and I didn't want to pay that much for the remote.
Plus the S-VHS VCR's are only good with S-VHS tapes which I have nada of, just regular VHS tapes.
Plus for just regular VHS Tapes a 4-Head Hi-Fi Stereo VCR is the best way to go for them without having to go to the extra expense of getting a S-VHS VCR that's not even gonna make a bit of difference in playback quality without having a S-VHS Tape.
If you get a 4-head Hi-Fi Stereo S-VHS unit and don't have any S-VHS tapes then its just going to playback just as if you had a regular 4-head Stereo Hi-Fi VHS unit and you might as well saved the additional $50-$300 and just buy a regular 4-head Hi-Fi unit for $10-$15 @ your local thrift store and be done with it.

[Electronic M]

You can record S-VHS quality on regular VHS tapes if you put a hole in the cassette in the right place, or if you get an S-VHS-ET VCR. S-VHS-ET was my favorite format for TV archiving (it is hard to tell the difference between it and live cable) until I switched to DVD-R a while back when blank tapes began becoming hard to find.

The remote situation depends on the VCR. Some of my JVC units have all user adjustments available on the front thru the menu buttons, others do not need an original remote to access anything except the timer recording functions. I got all my S-VHS decks from the local thrift shops for under 10$ a piece...They show up quite often here.

As a fellow otaku I'm sure you have found your self playing parts of tapes with the still frame function. In my experience a JVC with a good still frame JOG knob (especially the ones that boast a Pro Speck Drive) do a much better job tracking a still frame or scrolling thru frames getting much less video noise or snow than any normal 4-head HIFI VCR I've owned. Most S-VHS/-ET decks I've owned (And I own at least 6 S-VHS/-ET decks) tend to give better playback on normal prerecorded VHS tapes than my regular VHS machines.

You must have had an interesting model of JVC for the remote to cost a C-note. The remotes for mine cost me 30$ on ebay (which after using my machines regular for a couple of months I considered a worth wile entertainment expense) a couple of years ago and 1$ from the thrift stores later on when I found more remotes. I've also found that the remotes for the newer models work on the older ones.

[walterbeers]

If I remember right, there is a small electrolytic capacitor in a switch mode power supply that goes bad and it will not power up. If it is one of those that has the power supply on the right side toward the back of the unit where the power cord goes in, you can remove it, and recap it. If the fuse was blown then the switch mode SCR would be shorted, and it may have more problems. I'd try recapping it. Seems to me is just a little bugger, like a 4.7Uf or something kinda in the middle of the power supply that opens up and then the whole thing goes dead. Usually if I found one of those that had switch mode supply that was bad I recapped the whole thing.

[Captainclock]

Originally Posted by Electronic M

You can record S-VHS quality on regular VHS tapes if you put a hole in the cassette in the right place, or if you get an S-VHS-ET VCR. S-VHS-ET was my favorite format for TV archiving (it is hard to tell the difference between it and live cable) until I switched to DVD-R a while back when blank tapes began becoming hard to find.

The remote situation depends on the VCR. Some of my JVC units have all user adjustments available on the front thru the menu buttons, others do not need an original remote to access anything except the timer recording functions. I got all my S-VHS decks from the local thrift shops for under 10$ a piece...They show up quite often here.

As a fellow otaku I'm sure you have found your self playing parts of tapes with the still frame function. In my experience a JVC with a good still frame JOG knob (especially the ones that boast a Pro Speck Drive) do a much better job tracking a still frame or scrolling thru frames getting much less video noise or snow than any normal 4-head HIFI VCR I've owned. Most S-VHS/-ET decks I've owned (And I own at least 6 S-VHS/-ET decks) tend to give better playback on normal prerecorded VHS tapes than my regular VHS machines.

You must have had an interesting model of JVC for the remote to cost a C-note. The remotes for mine cost me 30$ on ebay (which after using my machines regular for a couple of months I considered a worth wile entertainment expense) a couple of years ago and 1$ from the thrift stores later on when I found more remotes. I've also found that the remotes for the newer models work on the older ones.

I actually no longer have the JVC S-VHS VCR I was referring to in my previous post, I donated it to Goodwill because it was such a huge unit and also because it didn't have its original remote (which for this unit it did need to have the original remote to do all of the extra functions), it was a model from 1987, and had solid wood panels on the sides of the unit, its model was HR-S8000 U, and yes the remote for that unit was $100.

Although actually though I do have a Pro-Grade VHS unit by Sony, a model SLV-575UC 4-Head HiFi VCR that has its original remote and even has a Swing Shuttle and D/A Pro 4-Head with High Speed Rewind (basically an early version of the modern 1 minute rewind that the Toshiba VCRS from the early 2000s touted) and On-Screen Display/Programming and basically all of the Bells and Whistles that every S-VHS VCR came with except on a regular VHS unit. The Sony VCR was a $10 Goodwill score.

IMHO I wasn't really all that impressed with the playback quality of my VHS tapes on that old JVC S-VHS unit, the picture quality was very grainy and the colors were a bit off compared to my Toshiba Model W-544 4-Head Hifi unit I also had at the time which was a freebie that I got from the High School that I went to/Graduated from. The JVC Also didn't have Digital Auto Tracking, or Digital Tracking in General, the Tracking had to be adjusted via a little control knob in the front panel.

Here's a link to an auction site listing showing the VCR that I used to have including a picture of it and apparently its extremely high going rate for it being a used 26 year old VCR. http://www.ebay.com/itm/JVC-HR-S8000...-/330916874120

P.S. the link above is NOT endorsing anything its just being used as a point of reference so that the person I was writing this reply to knows what the VCR I was talking about looks like by seeing the picture of it.

[Captainclock]

Originally Posted by walterbeers

If I remember right, there is a small electrolytic capacitor in a switch mode power supply that goes bad and it will not power up. If it is one of those that has the power supply on the right side toward the back of the unit where the power cord goes in, you can remove it, and recap it. If the fuse was blown then the switch mode SCR would be shorted, and it may have more problems. I'd try recapping it. Seems to me is just a little bugger, like a 4.7Uf or something kinda in the middle of the power supply that opens up and then the whole thing goes dead. Usually if I found one of those that had switch mode supply that was bad I recapped the whole thing.

Yes, you're spot on with where the power supply was in my unit, and there is indeed a 4.7 μF 200 Volt Capacitor right near the middle of the power supply board.
One wierd thing about this power supply is that it was soldered onto the main board on the bottom of the unit.

I will be trying to get a hold of some 4.7 μF 200 Volt electrolytic caps to replace the ones in both power supply boards.
And yes oddly enough this VCR has two power supplies in it.
None of the fuses were blown when I opened it up and checked them (I always check the fuses first thing when I get a non-operable VCR or TV).
So hopefully replacing the 4.7 μF 200 Volt Electrolytics in the Power Supply Boards should bring this VCR Back to life.