View Full Version : I really hate Mitsubishi TV's
radiotvnut 11-09-2009, 03:21 PM Or, at least the post-early '80's ones. Someone asked me to fix a '90 CS2610R that was said to be making a buzzing sound. When I checked it, I found the relay to be chattering. Otherwise, the set worked OK. I thought, "this one will be fine after I change the filter cap in the B+ line to the relay coil". WRONG! I replaced every cap in the B+ line to the relay, most of which were leaking severely. There were also some severely leaking caps in the audio output circuit. Changing out these caps and cleaning up the mess they made did no good. It seems that every Mitsubishi that I get from this time period have a boat load of leaking caps. I've fixed one problem on these sets, only to have them come back and bite me in the butt with another problem. I suspect that will happen to this set if I can get the relay to stop chattering. I think I'll advise the owner to get another TV and forget about this one.
DaveWM 11-09-2009, 03:25 PM I have a 1985, which is working fine. I wonder if it would be a good idea to recap it as a preventive measure? its a daily driver and has a great picture.
its the one that out with the 1st stereo audio (had to get that as I was a huge Miami vice fan).
radiotvnut 11-09-2009, 04:19 PM I think it was sometime in the mid '80's when they started using bad caps that would leak electrolyte all over the place. All the leaky ones in the one I'm trying to repair are Rubycon brand.
AUdubon5425 11-09-2009, 04:47 PM Sounds like their televisions weren't any better than their cars.
MRX37 11-09-2009, 08:00 PM I have a friend with a 27 inch 1992 Mitsubishi that's his daily watcher and works fine.
site123a 11-09-2009, 08:24 PM Maybe the relay itself is bad...
Findm-Keepm 11-09-2009, 09:35 PM From my repair notes for the CS2610R;
Check the solder joints on IC3A01
Check for (formerly) yellow glue that has cooked and become brown and conductive - this will cause tuner and vertical problems on similar Mitsu's.
A lot of Mitsubishi problems can be summed up as bad solder/solder starvation. We saw a great many intermittent problems in sets that were bounced around in military (Navy town I'm in) moves - a quick swipe with some 63/37 and a hot soldering iron fixed most. After the Sonys, Mitsubishis and JVCs, along came the RCA CTC185/187 sets and the later Thomson Chinese sets and their Pb free solder problems....
Dontcha just hate crappy quality?
Cheers,
radiotvnut 11-09-2009, 09:56 PM Yes, I hate crappy quality. At least those Mitsubishi sets made a great picture when they worked. Speaking of those Chinese RCA's, I have a 32" that is probably going to the dump. It is a 32" ATSC CRT set using the ATC010 chassis. It has the usual bad flyback and HOT. The last one of those that I replaced the HOT and flyback in came back as being "haunted". It would power on/off, change channels, etc. by itself. I replaced the front panel buttons and I guess that cured the problem.
BTW, I know the relay is good in the Mitsubishi because I pulled it and tested it with a 12V power supply.
kx250rider 11-10-2009, 09:56 AM It's not the relay... It's the input choke next to the relay, vibrating at 60 cycles! The first time I saw that, I went round & round also. The core is busted loose inside. You can either break it open and fill it with silicone, or replace it with one from another set.
On the Mitsubishi sets in general from the late 80s to the mid 90s, the caps are all bad. Especially the surface mount ones on the sets with PIP modules. And as other point out, that yellow glue that turns hard & brown, eats right through the dielectric coating on the board, and is 100% conductive. What a mess! I hate working on those, and they're trouble unless you remove ALL of that glue, and also replace a big bunch of caps. Great performers though.
Charles
Zenith26kc20 11-10-2009, 11:29 AM Mitsubishi.... The people who brought you Pearl Harbor!
If I remember right, Consumer Reports loved these capacitor eaters!
Be careful, the oil from the caps will destroy the Weller controlled heat tips in nothing flat.
If you can't get the PIP to work after feeding it a handful of caps, try a 1 uf@50volt cap on pins 5 to 11, 7 to 9. No PIP but it usually works again.
The 36" ones with the million shutdown circuits are fun too!
DaveWM 11-10-2009, 12:47 PM So I guess I should pull the back cover and look for brown glue? I normally dont fix something that is not broke but it is getting old...
I will get a model number an see if I can figure the vintage. I am wanting to think I bought it in early 85 so prob made in 1984.
radiotvnut 11-10-2009, 03:58 PM It's not the relay... It's the input choke next to the relay, vibrating at 60 cycles! The first time I saw that, I went round & round also. The core is busted loose inside. You can either break it open and fill it with silicone, or replace it with one from another set.
On the Mitsubishi sets in general from the late 80s to the mid 90s, the caps are all bad. Especially the surface mount ones on the sets with PIP modules. And as other point out, that yellow glue that turns hard & brown, eats right through the dielectric coating on the board, and is 100% conductive. What a mess! I hate working on those, and they're trouble unless you remove ALL of that glue, and also replace a big bunch of caps. Great performers though.
Charles
That indeed was the problem with mine! It's so close to the relay that it made me think that the relay was making the noise. I installed another choke from a junk chassis and it's now quiet. Now, I've got to replace the leaky caps.
radiotvnut 11-10-2009, 06:02 PM This TV is now mine. The owner decided not to spend the $ for the new caps and the RFI choke. I explained to him that the choke cured the noise problem; but, there were many caps that were leaking fluid and needed to be replaced. I think he really wanted to buy a flatscreen in the first place.
Findm-Keepm 11-10-2009, 11:37 PM Be careful, the oil from the caps will destroy the Weller controlled heat tips in nothing flat.
Thou speaketh the truth! That oil is Krypton to the Weller tips. Sony 8mm Video Cameras and Mitsu's - both full of leaky caps!
Cheers,
ctc17 11-11-2009, 10:50 AM The cars have the same issue where the caps in the computers leak juice and eat the board up. The same Mitsubishi computers were used in late 80s early 90s Mazda trucks.
I have an early 80s Mits monitor that had a bad cap in the vertical when it was given to me. Has been solid ever sense, running 18 hours per day for years now.
zenith2134 11-11-2009, 08:50 PM Well, I'd have to agree about the capacitors. Every set I found by them (or MGA) had either a short vertical due to them or some other strange erratic problem. But I did like the pinkish-tinted CRT's a hell of a lot. They have the potential to be great, great looking sets/monitors. One, a 26" with s-vhs input comes to mind. It didn't suffer from the capacitor issue (probably a lowhour set) and worked as found. I gave that 1 away IIRC and it looked stellar with a dvd.
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