Post #6,372
8/22/01 5:55:29 PM
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No 'scope, etc. More importantly, no time. :-(
Hi,
Thanks for the pointer to the repair FAQ. Lots of good information there.
But I've got too many hobbies as it is!!!! :-)
My dad is a EE with lots and lots of hands-on electronics experience, a 4 digit "general" (IIRC?) HAM license, etc. He's of the opinion now that "TVs are almost impossible to work on anymore." :-( If I had the time, and if it was just one thing simple, I'd probably try to work on it. But I don't. Not having an oscilloscope doesn't help.
It looks like it's potentially got problems with the tuner, IF or AGC circuits (26.1-26.2 in the FAQ), and the vertical circuit (21.8 in the FAQ). It doesn't look like a simple repair, especially since I don't have the repair manual for it (and a site Toshiba recommends for parts - [link|http://www.tritronicsinc.com|[link|http://www.tritronicsinc.com|http://www.tritronicsinc.com]] - doesn't have it any more). And it might be something relatively simple like a power supply common to both functions...
I'll do some final checking tonight just to make sure that it's not something simple. I'm good at missing the obvious sometimes. :-) After that, unless I have a breakthrough, we'll be doing our part to keep the economy going by buying more consumer electronics this weekend....
Thanks everyone!
Cheers,
Scott.
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Post #6,387
8/22/01 10:09:24 PM
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try looking at where the cable comes in with the cover off
there is (usually) a very wierd connection to the circuit board that can fry. have ya tried icing the circuit boards to see if it is heat related?
thanx,
bill
Our bureaucracy and our laws have turned the world into a clean, safe work camp. We are raising a nation of slaves.
Chuck Palahniuk
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Post #6,430
8/23/01 8:34:12 AM
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I think you're on to something.
Hi Bill,
We turned on the TV yesterday and after a few minutes it was back to its old self. The top of the screen is still chopped off (as it has been for months or longer), but the picture was pretty good. It's very likely an intermittent bad connection where the video signal attaches to something inside the set. It's been OK for the last 12 hours or more.
We'll leave it alone for a while to see if it stays stable. When I've got more time, maybe I'll take the back off and see if there's a cold solder joint or something...
Ashton, I appreciate the 'scope offer. I was thinking of you when I mentioned not having one. :-) But the need seems to have passed now. I may contact you in the future though!
So, no new set seems to be needed just yet. If the US economy falls into recession, you'll know who to blame...
Thanks for the help, everyone!
Cheers,
Scott.
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Post #6,570
8/23/01 11:42:33 PM
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Dry-joints and dodgy connections.
You will probably not be surprised at how many faults are a simple dry-joint (basically a manufacturing fault) or a piece that is under-engineered. Input sockets are classic favourites for the latter - when they haven't been engineered to take the weight of the typical lead and plug, well, guess what: they fail much earlier than they're supposed to.
Wade.
"All around me are nothing but fakes
Come with me on the biggest fake of all!"
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Post #6,401
8/22/01 11:31:51 PM
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Heh.. scopes? I got scopes.
5 MHz would likely do = Tek 305 same size as: a Tek 335, which is 35 MHz. Both weigh just over 10#, so UPS might be tolerable - where are ya? You'd just have to treat it nice - I've culled a few super clean 335s for long term. (No one will ever make stuff this good in any present, future Corp. Money + TLAs main 'product' now)
But 'time' I can't send. Can't hurt to just check PS volts at obvious points with DVM, or given your bizarre symptoms - Bill's easter egg might be it - if got good Karma. Now with a father experienced in this stuff - the physics and NTSC haven't er changed ;-)
Do sympathize re no schematic, though - still, PS checks might reveal all - with nose to find fried item?
Hey.. we gotta stop fillin up them landfills!
ashtonb[sort-of at]jps
and that horrible idea: .net
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Post #6,408
8/23/01 12:56:18 AM
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ya got spare scopes?
hmm wait a month or so and if ya still got spare scopes could definitely use one after Oct 1st. email is William Oxley cocatenated at netscape dot net nothing better than a scope to install awe in chirrun. Needs ta wait for the eagle to shit first slow boat is fine.
thanx,
bill
Our bureaucracy and our laws have turned the world into a clean, safe work camp. We are raising a nation of slaves.
Chuck Palahniuk
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Post #6,417
8/23/01 5:35:39 AM
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Umm best use my add
above - I see sev. ways to interpret yours, as in ..iam_Ox... but not ..iam Ox.. but maybe --> ..iamOx..
I'll ponder on a mainly demo for kids, but best let me know what other use you might have in mind. BW goes from teeny handheld 500 KHz -- on up. Have some needing minor fixing, thus for rilly cheap. All good lab-grade Tek, some HP, no TV-tech type beaters. Even teeny 4 MHz w/ batts. Cute but jeweler-hands needed. Should see the gold plate in such as the 335 (a Sony-Tek venture in '70s).
(What's amazing and of course depressing too - the occasional near-mint super lab-grade 7000 series (plug-in mainframes + beaucoup speciallized plug-ins).. going for <10% of last new cost.) Indicates to me that we are losing that always small part of population - who even know what to do with such equipment. They don't build kits; dunno how most stuff works.. and don't wanna know. They buy. Then toss, all unCurious.
Supply/demand in a dumth-increasing, MBA PHB culture - focussed exclusively on boring bizness. Our techno must soon reflect this absence of new talent, new explorers.
No more Numbah One, 'cept maybe in Reality Tee Vee games.
:[
A.
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Post #6,518
8/23/01 3:32:19 PM
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No gap no Space
nope, I want to do various low level stuff and am affierd that when I do need one it will be unavailable. Lat one I had was an HP with the FAA used it for all kinds of neat stuff.
thanx,
bill
Our bureaucracy and our laws have turned the world into a clean, safe work camp. We are raising a nation of slaves.
Chuck Palahniuk
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