Recapping JVC SR-MV45U: parts list?
 

Don't ask me why I do the things that I do, but I picked up another JVC SR-MV45U deck and I'd like to dust off soldering skills I haven't used in years, and attempt to re-cap the power supply board on it for practice, and because if I'm successful on a donor machine, I can move the board to my main deck and then recap that one and very like have two good working units. My two MV45U's were manufactured only a month apart, one in Feb 2007 and one in March 2007 and appear identical inside. It's interesting, having a second one around made me realize that they both could use a recap. The display on my first/main MV45U is very dim compared to the 2nd one, even when I set the brightness on high. And the 2nd unit mostly works but if you try to direct dub VHS > DVD-R, it only goes for about ten seconds, then shuts down and gets stuck on LOADING, and there's some kind of problem with the RCA audio out jacks on the shared DVD/VCR output port. That might not be an issue a recap of the power supply board would fix, but I think it would be a good starting point before digging into that further.

Anyway, I digress. I'd like to recap the power board on one, and then if successful, do the other.

To start, I took tons of photos and mapped my power supply board with every capacitor location and the values I found installed at each board location ID. The location IDs are organized into what appear to be different rails: C5003, the big beefy main 200v 330µF, then C5103 also by its lonesome, then C5201-C5210, and finally C5303-C5314.

Then I carefully put together a DigiKey cart with Panasonic, Rubycon, and Nichicon replacements based on what I could find in stock. I exported my DigiKey cart, then uploaded that, plus my manual inventory spreadsheet, and the service manual to the MV40 (which seems to have a very similar board layout) to ChatGPT and had it merge the spreadsheets to create a sort of "master table" combining my inventory along with the replacement brand, part number, and values, as well as an attempt to have it use the service manual to give its best theory on what the role of each capacitor is (for fun, it might be way off, I don't care too much about that, and haven't read the SM in-depth yet myself) so I can keep this all straight in my head. LordSmurf, you'll lose your mind at the fact that I used AI at all in putting this together, but I do think it can be helpful for situations like this, and this required a lot of manual attention to detail.

I've attached the project spreadsheet to this post, and I wonder if you'd be willing to glance through it to see if I'm on the right track with my planned purchases before I pull the trigger on this cart.

When you recap a power supply board, do you replace every single capacitor on it (What I'm planning to do) or do you typically only target problem rails? Is there an easier method than what I did, or is that what goes into every recap project?

Seems like it'll be affordable enough if I do the work myself, my DigiKey cart is only like $40 and that's because I'm buying enough quantity do do both boards.

I know the basics of soldering and know enough to discharge the caps, make sure their orientation is correct to the originally installed capacitors but I'll be watching any re-cap videos I can find on Youtube, it seems like there are lots of people who recap power boards in amplifiers and the like, so there's probably plenty to glean from those as well before I actually start the real soldering.

Thanks for any advice or words of wisdom you may have for me. I don't think I am very far off with my DigiKey cart, but I'd really value an expert pair of eyes or two on it to look for any glaring mistakes I may have missed, or if you have specific brands you favor. For instance I didn't seem to find 27µF 35v so went with 33µ 35v which I hope is within range of being acceptable.

The SR-MV series uses low quality caps on everything other than (sometimes) the main filter cap and the taller brown ChemiCon caps. The main filter cap that doesn't tend to go bad are Panasonic branded, so you can probably leave all of those as they are. The rest of the caps on that are Lelon branded which generally have not aged well and should all be replaced if they are in high heat areas like a power supply. It's possible if you have a super low hours unit that you might not technically need to recap anything, but if you want longevity and something future proof, that's what I do when I recap mine.

Lastly, if your SR-MV series machine is stuck saying "loading" when you try to power it on, there's no guarantee that recapping it will bring it back, but it does work I'd say over 50% of the time, but that's not a great success rate.

Perhaps mercifully, neither of the units are to that point yet. My first unit doesn't say LOADING at all when you plug it in (which in itself might be some kind of sign to people more familiar with these units), and the second unit says LOADING for about 40 seconds when you plug it in, then the display dims and acts like you've hit the power button (turns off with --). Then you can hit the power button and it says something like WAKE-UP for about 10 or 20 seconds, and then it's usable. There's also some gremlins in the output switching circuitry on this one. To wit: on the shared VCR/DVD output board, S-Video and Composite Video work for tape playback, but not the left and right audio outs. When playing a DVD, there is no audio or video out the shared ports (and I've made sure it's not trying to send Progressive), however the DVD-only ports work. I've only done some basic tinkering on that like re-seating all the ribbon cables. Will a recap fix that? I don't know, but I theorize it could if the power rail serving the processing and switching chips is out of spec. It at least seems like a freshly recapped power board is a good foundation from which to start further troubleshooting.

For my original MV45U it plays tapes fine, but has a dim front display even when it's set to high (maybe 1/3 the brightness of my other unit) and the DVD drive doesn't work--"Unreadable Disc" error. And now that I can compare units, I don't think the TBC is making as noticeable a difference to the VHS image as it does on the 2nd unit. So again, I think giving it a clean recapped power board is a good starting point before any further troubleshooting.

Admittingly I'm not exactly looking forward to the work. Through-the-hole soldering is as basic as it gets, but with this many capacitors it's tedious, and some of the main ones are really clustered rather tightly together. And this is where I think the most important ones, the C52XX line lives.

Attachment 20349

I've placed the order. I did realize that I'd originally chosen snap-in style for the 200v cap, so I've replaced that Nichicon with a Rubycon 220TXW330MEFR18X35. 330 µF 220v, rated for 12,000 hrs at 105°C

I've got some Kester 44, 63/37 0.031" leaded solder wire, an RMA soldering flux pen, and a PCB board holder on the way, and I already have an 80w soldering iron with chisel tip, solder sucker, resoldering braid, 99% alcohol, a 5x magnifier light and some bright work lights and some Kaptan tape to use if I need it, so I think I'm basically ready to go once everything arrives.

I'm just planning to take my time and replace one at a time, starting with some of the easy small onces before I get into the bigger, maybe more challenging ones.

Interesting on the unit that doesn't say "loading" at all when you plug it in. I've worked on probably 20 of the SR-MV series and have absolutely never seen that. I suppose it could be some sort of alternate firmware perhaps where it doesn't do startup checks.

No, you're actually correct. I checked it again and it does say LOADING, it's just really dim. It flashes LOADING for about 35 seconds, then the display dims to the point you almost can't see it, then it says LOADING for a few more seconds, then goes to --:-- on the screen just like the other one. The timings and behavior seem at least roughly the same across both units.

Sorry about the mix-up there. Truly don't know where I got it in my head that one didn't flash LOADING. It's dim, but it's there.

-- merged --

Well, I come with an update bringing mostly good news!

The recap project was, on the whole, a success. I had a heart-attack moment when a pad lifted, but I was able to solder a little jumper wire to a test point that was mercifully less than 1cm away and saved it.

My crappy "80w" pencil-style iron was definitely not up to the challenge, so I picked up a T12 knockoff (YIHUA 948DB+ II) on Amazon for about $60 that performed quite well. Night and day performance difference. For removal I applied flux, then added some new leaded solder, then sucked it all up, then applied more flux and used leaded solder for the new caps. My technique is amateur at best but overall it went pretty well.

In case this can be helpful to anybody in the future, here's my final spreadsheet where I logged all the board location numbers and capacitor values, and it includes the brand and model of the replacements I used.

JVC SR-MV45U Power Board Replacement Google Sheets

I think it looks...pretty with all the new capacitors. The big ones have really shrunk since 2007, I had to double-check my values because some of them were almost half the height of the originals.

Attachment 20405

It doesn't appear to have made a lick of a difference on the MV45 with the signal routing issues, and didn't even fix the "LOADING" crash after about 10 seconds of VHS>DVD-R dubbing. Zero observed change.

However, I moved the recapped power board to my first MV45 and it DID fix the DVD "Unreadable Disc" error. Both VCR and DVD now work on that unit. Although, strangely the front VFD display still looks dim. Maybe it's the lens material?

So I call that a win, as I now have one solid fully-working unit with a fully-recapped power supply board.

I'm hanging onto the other MV45 for now, and I do have all the capacitors on-hand I will need to recap the other power board. Soon, maybe this summer I'll recap that one and try to further troubleshoot that unit.

The thought is not lost on me that, with what I've now spent on that first 5400 unit, plus what I've spent on these two MV45's and new soldering iron I could have just gotten a decent non-TBC unit from the recommended list, but it was a great learning experience, and at least now I have one fully-working unit that seems to be a pretty decent VCR!

Lastly, I did find the Service Manual for the SRMV-40 unit helpful, as it seems they share many of the same components and boards. Since I have an Acrobat Pro license at work, I OCR'd the scanned service manual PDF and I'm attaching it here, in case it helps anybody down the road.

I just noticed one small discrepancy in my spreadsheet. For location C5003, the replacement Rubycon 220TXW330MEFR18X35 is actually 330µF 220V not 200V as my spreadsheet and the quoted data says. It's probably neither here nor there but in the interest of completeness I wanted to mention that.