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Success Stories If you have successfully repaired or restored a piece of equipment, why not write up what you did and post details here. Particularly if it was interesting, unusual or challenging. PLEASE DO NOT POST REQUESTS FOR HELP HERE!

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Old 24th Nov 2008, 2:08 pm   #1
Studio263
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Default The No.1 Ladies Television Shop

I've just come back from visiting my wife's family and friends in Zimbabwe and one of my tasks whilst there way to fix her mother's TV set. Because of the sanctions a new set would be very expensive (from about US $1000 if you can find one) and there are no parts availalbe so she has gone without a set for about 2 years since this one went wrong.

The set itself was a Panasonic TC-2000 (see the first picture) which I did not recognise. It's a 20" multi-standard job with a UHF / VHF tuner and wide range (100 > 240V) power supply. The chassis looked a bit like those fitted to some Panasonic portables sold in the early 90s but in detail was quite different. In particular the power supply is odd, it is nominally a series chopper (like a Philips KT3) which feeds the line output stage which as well as it's normal function also provides mains isolation for the rest of the chassis. The chopper also has a few isolated tertiary windings that provide a couple of supplies for when the set is on standby, to make these effective the main HT rail is shorted out by a MOSFET controlled by an optocoupler when the set is not in use. There is also a crowbar thyristor, this little lot makes the whole layout somewhat confusing.

Also to add to my troubles the set really was in the middle of nowhere (see the second picture) in a place called Bushmead Township. This is located some way up a dirt track a some miles from the town of Masvingo. I had a few carefully chosen tools and parts with me but as the set is not one I know (or have any information for) these were assembled purely by guesswork. To complete the picture, the only place I could plug the iron in was in the kitchen where three African women whittered away in Shona non-stop as I struggled with the unfamilar circuitry. Oh, and the mains comes and goes randomly and the voltage tollerence is not quite what we are used to in the UK...

And so to the repair. The set was dead without even the standby light showing. The power supply was complaining quietly (unlike the women...) going chirrup-bonk chirrup bonk. Luckily there had been no local attempts at repair, in fact the set seemed untouched from new which is surprising given the quality of the mains and that they never seemed to turn the wretched thing off. The line output transistor showed a 470R leak C to E in circuit but after a long time this proved to be a red herring, I was really measuring a resistor some way away in the power supply (I told you it was confusing!). I spotted two bulging electrolytics on the isolated side of the chopper transformer but changing these (one thing I did have was plenty of electrolytics, it's a hot country remember) made no real difference. Undeterred I pressed on. There were two 47uF electrolytics in the chopper circuit, one of which was near some hot resistors. Both measured poorly but replacements only silenced the chirrup-bonk noise, the set still didn't work and there were still no external signs of life. Meter checks did show some activity, a 25V rail was present and stable so by rights something should have been happening, even if it was just the standby light comming on. I then struck gold, a 7805 regulator had 25V at its input but nothing at its output and was running cool. I had brought some 78-series regulators with me, I don't really know why as few sets use them, I must just be lucky. A new one was quickly fitted and on re-assembling the set and trying it the standby light blinked and then the sound boomed out (to much applause!). After a while a reasonable picture appeared on the slightly tired tube so I tweaked a few things up and boxed it up, much releived.

My celebration was short-lived however as a 28" Philips "Classic Line" (you know, the one with the wood stuck on) set was then wheeled out of a back bedroom. This had apparently been bought in the UK and used in another house until it had gone off with a big bang sometime in 2003. My heart sank, you may remember my unpleasant tussle with a Philips FL1.1 that was described here a year or so ago and that was in the UK with parts, manuals, stable power supplies and advice all close at hand. Still, there wasn't much else to do so wearily I removed the back. To my surprise, the mains fuse was intact and neither the chopper or line output transistors were shorted. I then tried the mains switch (with the set unplugged) and found that it was jammed. I think the switches were problematic on these sets, being similar in construction to those that led Sony to do that big recall in the 90s. Sure enough, having removed the chassis (a really struggle with the poor layout of the wiring etc, and it was filthy) and retrieved the mains switch panel from under the tube. The switch was found to be charred and some of the print was blown off the board. I didn't have a suitable switch with me so I cut the pins off the one that was there to remove it from the circuit and bridged around both it and the now absent print. Putting things back together (another dose of grief) and trying it produced a blue screen, and once the remote control was found and the set tuned in a very good picture was displayed.

This produced an awkward situation. The Philips had a much better picture than the tired Panasonic but I felt that the latter was a sturdier design and less likely to give trouble in the future so I recommended that the Philips set was sold (it's worth good money out there, given the price of a new one) and the Panasonic retained for viewing purposes. I think everyone thought I was a bit mad and since when did anyone pay any attention to what the TV repair man says but this was how I left things, we shall see.

So after that I called it a day (well almost, more later). Despite the difficulty of repairing sets in Zimbabwe there is one concession, check out the money they use (see the third picture). Try writing out a bill for a repair like that here!
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Old 24th Nov 2008, 2:19 pm   #2
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Default Re: The No.1 Ladies Television Shop

Great write up - and really well done!
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Old 24th Nov 2008, 2:37 pm   #3
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Default Re: The No.1 Ladies Television Shop

Well done indeed. All sorts of interesting questions, such as were there any problems bringing a load of suspicious looking parts and tools into Zimbabwe.

Is the paper the money is printed on worth more as scrap than it face value
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Old 24th Nov 2008, 3:06 pm   #4
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Default Re: The No.1 Ladies Television Shop

Well done Studio263. When I was last in Zimbabwe the hotel TV was housed in a rather crude plywood cabinet. Proudly written on the back were the words "Made in Zimbabwe". Well the cabinet was. but my overwhelming curiousity made me remove the back to reveal that the innards were "Assembled in The Republic of South Africa".

I remember that the TV progammes included repeats of very old third division UK football matches which had been recorded in black and white.

I still have a few Zimbabwe Dollars from those days, but they now worth less than the Zambian Qwacha sp?? Which no one wanted back then. We used to give them as tips if we got particularly bad service.
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Old 24th Nov 2008, 3:50 pm   #5
Al (astral highway)
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Default Re: The No.1 Ladies Television Shop

Quote:
Originally Posted by Studio263 View Post
I had brought some 78-series regulators with me, I don't really know why as few sets use them, I must just be lucky.
What a superb story describing rather a lot of intuition and ingenuity stirred together with a dab or two or good luck. All in all amusingly told and a good read. I can imagine the scene in customs:

'What are these, sir?'
'Oh, just 78-series regulators.'
'78 series? You're sure about that? Remove one from your case please, sir, and demonstrate how you will use it.'
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Old 24th Nov 2008, 4:32 pm   #6
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Default Re: The No.1 Ladies Television Shop

Very interesting.

Did you read the similar article by Joe Cieszynsky (sp?) in Television about ten years ago? Lots of incredibly worn audio heads ISTR.

N.
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Old 24th Nov 2008, 5:21 pm   #7
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Default Re: The No.1 Ladies Television Shop

A wryly amusing story, with references to the state of Zimbabwe (perhaps we are presently heading in that direction, minus the good weather). Very enjoyable read. Thanks!
-Tony
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Old 24th Nov 2008, 6:18 pm   #8
Mike Phelan
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Default Re: The No.1 Ladies Television Shop

Tim
A fantastic write-up - well done; we only had Manchester 15 and Salford 5 to deal with. Scary place. Zimbabwe, that is.

Nick
It's Joe Cieszynski - we worked together many years ago.
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Old 24th Nov 2008, 6:27 pm   #9
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Default Re: The No.1 Ladies Television Shop

Shows what us engineers can do doesn't it. TV sets repaired while visiting relatives in Zimbabwe.

Cheers,

Steve P.
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Old 24th Nov 2008, 6:28 pm   #10
Studio263
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Default Re: The No.1 Ladies Television Shop

In reply to a few questions, the only difficulty I had with customs was in the UK, I'd packed all my tools and parts (such as they were) in the luggage that went in the hold becasue I didn't want them to get confiscated (they may have thought that I wanted to stab the pilot with a BY127 diode otherwise). What I did have was an apparently dangerous quantity of toothpaste in my hand luggage so my bag got searched. The young chap who did it was so impressed with my Sony cassette recorder ("wow, that's so cool!") that he let me off on the toothpaste thing, as I predicted once all the peasants have I-Pods the man with the Sony Walkman clearly is king. The one in question was a TCS-310, you can see it on www.walkmancentral.com

One thing I didn't mention is that the Panasonic set replaced a Philips 24" monochrome hybrid model that was still there, burried under a pile of clothes in one of the bedrooms. It was a model that I've never seen before and I have a few pictures of it inside and out so if anyone is interested in African TV sets (and the forum rules allow it) I can post them in the vintage TV section.
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Old 24th Nov 2008, 6:32 pm   #11
Brian R Pateman
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Default Re: The No.1 Ladies Television Shop

Quote:
Originally Posted by Studio263 View Post

.... It was a model that I've never seen before and I have a few pictures of it inside and out so if anyone is interested in African TV sets (and the forum rules allow it) I can post them in the vintage TV section.
No reason why not it will make a nice change from home grown sets.

Regards,
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Old 24th Nov 2008, 10:41 pm   #12
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Default Re: The No.1 Ladies Television Shop

Hi Tim.

What a fantastic story. Now that really is television repair against the odds. Well done. I look forward to seeing the pics of the Philips hybrid set.

Regards,
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Old 24th Nov 2008, 11:29 pm   #13
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Default Re: The No.1 Ladies Television Shop

Great story, thanks for the write up!
I was in Zim about 12 years ago, and I seem to recall there being panasonic 14" in the hotel room, to which I struggled to attach our panasonic M7 video camera!

My only similar experience was helping a cuban friend fix his PC and tweaked his Tv (no great odyssey like your experience!) whilst over in Cuba a few years ago. Fortunately, despite the embargo there are a fair few telllies about, lots of RCA and 'Panda'. I also saw a few carcasses of old, presumably Russian made sets on the street.

Here's a pic of the local repair shop, proudly announcing repairs to black and white and colour sets (close up of the list in 2nd image)!

http://www.fileden.com/files/2007/6/...air%20shop.jpg

http://www.fileden.com/files/2007/6/...20rep%20cu.jpg
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Old 25th Nov 2008, 1:31 am   #14
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Default Re: The No.1 Ladies Television Shop

Excelent story. My last involvment with one of those Philips sets almost resulted in loss of sanity. The only way I could get it to run was by disconnecting one of the protection circuits! I was either that or write it off and it was only a couple of years old then. Hopefully its been scrapped by now.
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Old 25th Nov 2008, 3:41 pm   #15
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Default Re: The No.1 Ladies Television Shop

Excellent story and very well done, Just shows, us tv engineers cant really put the soldering iron down!
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