JVC LT-32A61SJ Stuck in standby

[bbjunkie]

Finally took delivery of this TV today, had bought it on eBay a few days before Christmas, but the shipping company have messed us around with failed collections etc meaning it only arrived with me yesterday.

Got stuck into it this evening, back off and first impressions are this is a quality build. Lots of metalwork and it feels strong (there is even a hole in one of the plates that looks a perfect size for a small 100mm computer type fan including the mounting screws) I may fit one here if I can find a good 5v supply nearby.

I am glad to report that there are no signs of anyone having been in here before me, so hopefully I will find no nasty surprises along the way.

Ok, on with the repair.. <Yes, this time I checked - this one is definitley stuck in standby, not 2 seconds to black!> I went straight to the caps on the PSU, and didn't have to look much further for signs of what could be wrong - 7 CapXon caps of various values with domed tops.

2x 2200uF @ 35v 105c (C42 and C43)
1x 1200uF @ 35v 105c (C44)
1x 1000uF @ 25v 105c (C22)
3x 470uF @ 25v 105c (C20 C21A and C21B)

I have the power supply out of the set now and will proceed to remove all caps in the secondary side and test. I plan on keeping this TV, it has no pedestal stand but should work well in my bedroom on a wall bracket. Therefore, long term reliability is paramount!

The PSU in this TV has a LOT of transistors, four hefty heatsinks with a total of 8 transistors, 2 diodes and the bridge rectifier bolted to them. The P/no is QAL0826-001

Once the caps arrive I will post my progress along with some pics of the board.

Again, thanks guys for the great resource that is the badcaps.net forum, without this I wouldn't have the knowledge or confidence to tackle this job.

Jim

[tom66]

Re: JVC LT-32A61SJ Stuck in standby

JVC using CapXon?

I'm very disappointed.

Just for laughs, measure the output voltages with the bad caps. Are they zero, or just low? In most computer power supplies with bad caps, the voltages become low (but are still there.)

Post a picture of the rest of the TV (so we can see how well built it is... aside from the capacitors, of course...)

[bbjunkie]

Re: JVC LT-32A61SJ Stuck in standby

Indeed, I have a 2007 JVC 42" LCD 1080p in my main living area, and am now wondering if I should do a recap on it before they cause damage to other components. (It is behaving itself currently)

Will post pics and test results tomorrow before I pull the caps.

[retiredcaps]

Re: JVC LT-32A61SJ Stuck in standby

Finally took delivery of this TV today, had bought it on eBay a few days before Christmas, but the shipping company have messed us around with failed collections etc meaning it only arrived with me yesterday.

I don't know what you paid for it, but a fully working one went for 60 pounds.

http://www.ebay.co.uk/itm/230728292496

PS. I got a free "working" ATX no name power supply. Before I plugged it in, I saw bloated caps, but thought I would measure the voltage of the pinouts anyway. 2 seconds after I applied power, I smelled the magic smoke.

[bbjunkie]

Re: JVC LT-32A61SJ Stuck in standby

In the end I paid £34 for it, got refunded the shipping due to the fiasco with the courier. Probably still a bit over the odds, but at least when I add the cost of the caps it'll be more reliable than the one which sold on eBay.

[tom66]

Re: JVC LT-32A61SJ Stuck in standby

Generally I'd sell a working 32" of that spec for around £100 - £150. The linked TV was pick up only & so went for less. Would make a nice bedroom TV if fixed up.

Generally I've seen JVC TVs (LCD and CRT) to be very good, so I'm guessing this one is a lower end model - for example, most lower end Toshibas were made by Vestel a few years back. The only brands left you can trust, it would seem, are Sony and Panasonic, and I'm not sure on either...

[retiredcaps]

Re: JVC LT-32A61SJ Stuck in standby

If you really want to get TV/LCDs for free or cheap, I have seen the following methods work with some degree of success:

1) Post an advertisement in every local electronic ad/freecycle/kijiji/etc in your city that you will recycle non working TVs, computers, etc for free.

2) Get to know your local recycling depot manager.

3) Offer to buy non working TVs. If I were do to this, I would be extremely picky about certain models. If you pick a model with known bad caps or voltage regulators (Vizio), then you can have an easy fix.

PS. I found this forum today. It is the UK Vintage Radio Repair and Restoration Discussion Forum, but the have other subforums like TVs, etc.

http://www.vintage-radio.net/forum/

I'm definitely going to check out Vintage Test Gear and Workshop Equipment subforum.

edit: I'm jealous.

http://www.vintage-radio.net/forum/s...ad.php?t=75907

"Answered a freegle advert today for a DMM and was handed over a Fluke 79"

[tom66]

Re: JVC LT-32A61SJ Stuck in standby

I have done 1), 2) and 3). 1) does not return any results but 2) and 3) do, I have to pay for every TV I get (not much) but I've only had trouble with two so far. Plus, I like a good challenge.

[bbjunkie]

Re: JVC LT-32A61SJ Stuck in standby

1 worked for me, I had to go collect two yesterday. One a 50" plasma with broken screen (good source of boards) and a second, a LG 42" plasma with screen intact, no mention of what the fault was, but I hope to get it into the workshop in the next day or so (maybe even later today) damn, I had no idea there was such a difference in weight between the LCD and Plasma!

Well, got the caps out of the JVC PSU - I had 4 removed when I remembered tom66 asked me to do voltage checks, so I hope you will understand I didn't want to refit them (the board is double sided and I didnt want to run the risk of overheating tracks etc)

Anyway, all caps removed and the following was noted:

C25 (3300uf) 3596uf 0.02 ohms
C26 (3300uf) 3642uf 0.03 ohms (just outside 10% tolerance but on the HIGH side!)
C27 (1000uf) 1104uf 0.1 ohms
C27B (1000uf) 1074uf 0.12 ohms
C22 (1000uf) 395uf 0.4 ohms
C21B (470uf) leaky 3.6 ohms
C29 (100uf) 99uf 0.44 ohms
C20 (470uf) leaky 2.8 ohms
C21A (470uf) leaky 3.2 ohms
C44 (1200uf) 406.3uf 0.27 ohms
C42 (2200uf) 409.8uf 0.28 ohms
C43 (2200uf) 424.6uf 0.26 ohms


Those marked in red I am sure are requiring replacement. In theory (im replacing them all anyway) are others are pretty much OK?

Now I have the caps removed I can measure their sizes to make sure I get the right ones. Probably going to go for Panasonic FM/FC caps on this one as I want a reliable tv that can stay on the wall once fitted.

tom66 - I was wondering why that other JVC went so cheap, and yes I guess it went at a real bargain price due to lack of interest in the area he lives (no shipping)

retiredcaps - thanks for the links, I will have a look at them.


Jim

<edit>

Pics added, components missing from PSU board in the pic are all caps mentioned above, 2 heatsinks and two diodes (removed for access)

[tom66]

Re: JVC LT-32A61SJ Stuck in standby

C27 and C27B are also bad (should be <0.05 ohms).

[bbjunkie]

Re: JVC LT-32A61SJ Stuck in standby

Caps ordered, will resume this thread when they arrive.

Thanks tom66 - I wasn't aware C27 and C27B were out of spec.

Jim

[tom66]

Re: JVC LT-32A61SJ Stuck in standby

What's the capacitance of the main bulk filter? Manuacturer? Looks like it might be a Hitachi (hooray) or a Fujyuhhu (however that is spelt, I can never remember it.)

If these caps don't fix it (rare) check the output diodes and startup cap.

Good luck

[retiredcaps]

Re: JVC LT-32A61SJ Stuck in standby

C27 and C27B are also bad (should be <0.05 ohms).

Indeed, Panasonic FM are 18 mOhm in 1000uF 25V format.

[retiredcaps]

Re: JVC LT-32A61SJ Stuck in standby

1 worked for me, I had to go collect two yesterday.

See, it works. You just got to have patience and "renew" your ads every 60 days or so.

[tom66]

Re: JVC LT-32A61SJ Stuck in standby

Indeed, Panasonic FM are 18 mOhm in 1000uF 25V format.

It might work with the 0.1 ohm ESR but they are on their way out and it won't last long.

[bbjunkie]

Re: JVC LT-32A61SJ Stuck in standby

Took delivery of 40 caps today (RS only sell caps in bags of 5)

Very impressed with their service, ordered Sunday night, arrived 11.55am Tuesday (by 24 hour courier) and the best of it was, there was no carriage charge, digikey wanted £12 (approx $18US) for delivery!

I don't mind buying in 5's as I will more than likely require them sooner or later for other repairs.

Will post an update later when I get these fitted (after I clear the seriously heavy 42" LG plasma of the bench!)

[bbjunkie]

Re: JVC LT-32A61SJ Stuck in standby

Generally I've seen JVC TVs (LCD and CRT) to be very good

The only brands left you can trust, it would seem, are Sony and Panasonic, and I'm not sure on either...

I found out recently that JVC is actually a brand owned by Panasonic.

Perhaps this is reflected in the build quality of the main part of the TV, I'm very surprised that they have used such cheap crap caps in what seems to be otherwise a relatively high quality product.

[tom66]

Re: JVC LT-32A61SJ Stuck in standby

JVC used to be owned by Panasonic but they are no longer. Panasonic sold their stake in 2008. Kenwood Electronics and JVC are now the same company.

It's quite likely that Panasonic had influence on the design, because JVC would then have access to the same factories and mechanical knowledge.

As Panasonic make their own capacitors, it seems strange that most Panasonic TVs I have seen on this forum have very few Panasonic capacitors!

[bbjunkie]

Re: JVC LT-32A61SJ Stuck in standby

Is there any issue using arctic silver as a heatsink compound instead of the standard white silicone grease used by the factory?

I've misplaced my silicone grease.. have ordered some but it wont be here for a few days.

I guess the arctic silver is electrically conductive, the white compound isn't.

There are no mica insulators between the devices and the heatsinks.

[tom66]

Re: JVC LT-32A61SJ Stuck in standby

Is there any issue using arctic silver as a heatsink compound instead of the standard white silicone grease used by the factory?

I've misplaced my silicone grease.. have ordered some but it wont be here for a few days.

I guess the arctic silver is electrically conductive, the white compound isn't.

There are no mica insulators between the devices and the heatsinks.

Is it conductive? I thought it had a very high resistance.

There is no harm in using Arctic Silver IF it is not conductive. It is better stuff and has a lower thermal resistance, but that probably doesn't matter too much.