21st Jul 2021, 8:01 pm | #81 |
Hexode
Join Date: Aug 2018
Location: Dublin, Republic of Ireland.
Posts: 494
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Re: What was the worst CRT TV to work on and why?
My two CA10 sets are still running great, the first one belonged to my stepmum from new and it was only about two years old when the power supply blew up, local repair center said it was like it got hit by lightning as the main micro had lifted off the board. She stored the set for years hoping to one day get it fixed and i always liked it so in 2006 she gave it to me, in 2010 i found a replacment board for it and aside from a replacment Flyback its been working perfect ever since. The second one I picked up on gumtree about 5 years ago because it was in immaculate condition and thats been working perfect since the day i got it, the only gripe i have with the CA10 on both sets is the Micro can sometimes be a bit slow to respond to remote commands usually when changing the volume
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27th Jul 2021, 3:51 pm | #82 | |
Octode
Join Date: Sep 2020
Location: Thetford, Norfolk, UK.
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Re: What Was The Worst CRT TV To Work On & Why
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27th Jul 2021, 3:53 pm | #83 | |
Octode
Join Date: Sep 2020
Location: Thetford, Norfolk, UK.
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Re: What Was The Worst CRT TV To Work On & Why
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27th Jul 2021, 4:01 pm | #84 |
Dekatron
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,274
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Re: What was the worst CRT TV to work on and why?
From my amateur and limited experience I can't say that I liked working on a Sony 9-90 because of the inconvenience of wiring between assemblies.
Peter |
27th Jul 2021, 6:23 pm | #85 |
Hexode
Join Date: Jan 2007
Location: Faro, Portugal
Posts: 270
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Re: What was the worst CRT TV to work on and why?
Yes, the 9-90 isn't a pleasure to work on at all.
Removing the system switch assembly to gain access to the signal board is real battle. The previous 9-306 model was much better with its vertical boards. Hugh |
27th Jul 2021, 8:58 pm | #86 |
Hexode
Join Date: Aug 2014
Location: Featherstone, West Yorkshire, UK.
Posts: 386
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Re: What was the worst CRT TV to work on and why?
Thorn 3000/3500.
As a very young (and inexperienced) apprentice, I was faced with an power supply with L602 open circuit. To my befuddled brain, an inductor was just a piece of wire wound into a coil, so I shorted it out. Six months later, I knew how the power supply (and the rest of the circuits) worked. From then on, it was my favourite set. |
27th Jul 2021, 9:55 pm | #87 |
Octode
Join Date: Apr 2005
Location: Peterborough, Cambridgeshire, UK.
Posts: 1,898
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Re: What was the worst CRT TV to work on and why?
I liked the 3000 / 3500 and found they were easy to repair even though I was young at the time. it was only really the power supply and line stage / EHT stage that gave much trouble. The IF, Decoder, RGB and frame stages were pretty good the odd thick film, occasional Callun capacitor and gun switch aside...
One of the most devastating faults was when a wire-wound went o/c on the 3500 convergence panel that could burn a big hole in the panel and write it off but luckily but the time that fault started to occur there were a few scrappers about as donors. I had a 19" 3000 with a poor tube that I used as a jig to repair and soak test panels in. I would fit a loan panel to keep the set working and then return the original once it had been repaired and tested that way I didn't have to haul great big sets with doors about. I sold a few used ones in the early 1980's and was demonstrating one to a potential customer when there was a loud crack a hum and a cloud of smoke as the 15R glowed red hot before it tripped the cut out. I just calmly carried on and said "or there's this one" moving on to the set at the side of it.. The customer never said a word and bought the other set! Rich |
27th Jul 2021, 10:46 pm | #88 |
Nonode
Join Date: Mar 2010
Location: Sunderland, Tyne and Wear, UK.
Posts: 2,476
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Re: What was the worst CRT TV to work on and why?
The Thorn 9K8 series weren't too bad once you remembered the 'kick start' circuit to get the PSU going and that most supplies were now Lopt driven from the DST transformer, yes a budget set made up as a parts bin special, but I still found them superior to the previous 8k8 offering.
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28th Jul 2021, 9:19 am | #89 |
Octode
Join Date: Apr 2005
Location: Peterborough, Cambridgeshire, UK.
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Re: What was the worst CRT TV to work on and why?
Mitsubishi also did a set with the model number CT200 I had forgotten about those sets until I was talking to a friend recently about this thread. I'm not sure if it is the set I mentioned before with the plug in modules that suffered bad soldering and lead through connections becoming intermittent as I cannot remember what the chassis looked like.
It had a massively complex (I think simple PAL) decoder bristling with FET transistors and was very sensitive to flash overs . My mate still remembers to this day battling with them. He worked for a Mitsubishi dealer and dreaded one coming in for no colour as the fault was usually multiple transistor failures of which there were many. With the PYE CT200 the decoder was just about the best bit! |
28th Jul 2021, 9:56 am | #90 |
Nonode
Join Date: Jan 2004
Location: 1966-1976 Coverack in Cornwall and Helston Cornwall. 1976-present Bristol/Bath area.
Posts: 2,967
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Re: What was the worst CRT TV to work on and why?
One of the earliest TV's that I can remember that we had on rental was a Pye 40F. It was only working on 405 as it was before BBC2 from Caradon Hill opened. The few repairs that were were required were done in house and it was only taken away for repair when this strange fault occurred. The picture was a mass of lines with a buzzing hum on the sound. It turned out it was an AGC fault on the IF board that was part of the integrated tuner. Whilst it was away we were loaned a small BRC 980.
We also lost two tuner buttons on different occasions. Both fired across the sitting room at high velocity. One hitting our German Shepard dog who was not pleased and blamed me thinking I had fired my catapult at him. The second one ricocheted around the room before landing in the open fire which was lit at the time. But I will give the 40F its due the pictures on both 405 line channels were very good and when BBC2 first opened by connecting the VHF 405 aerial to the UHF socket we could get a snowy BBC2 picture on 625. Trouble is the system switch got stuck and despite it being a rental set and it was around Christmas my Dad opened up the back managed to slide the system switch back to the 405 position. By the time I started work in the trade some eight years later I never saw a Pye 40F apart form a few on the scrap heap but did see some of the later Pye dual standard sets such as the 67 and the 368 chassis which I did enjoy repairing and they did give good accounts of themselves. Ref the Thorn 9800. I actually did enjoy working on these sets although they did have a strange habit of destroying the IC's in the decoder and IF. But I always thought they were a step up from their previous 8500 and 8800 offerings. The pictures were far better and far more stable which I think was due to an improved Line Output stage and the RGB output transistors running from a 240v boosted HT line instead of from the 180v HT line.
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28th Jul 2021, 12:16 pm | #91 |
Dekatron
Join Date: Apr 2005
Location: North Wales, UK.
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Re: What was the worst CRT TV to work on and why?
Yes - the Mitsubishi CT200 was a bit of an acquired taste, and the colours could be, er, interesting. I didn't see too many unike the CT202 (seven tuning buttons as opposed to four). That was very reliable with odd colour faults - in fact all sorts of faults - due to two 47uF 160v capacitors drying up.
One set I didn't like was the old Sharp 2051 (I think) with a vertical modular chassis. Never seemed to get them going properly. |
28th Jul 2021, 12:46 pm | #92 |
Dekatron
Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
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Re: What was the worst CRT TV to work on and why?
The Pye 367 was a breath of fresh air after the 40F. It had a sensible sized I.F. panel and performed very well. It did suffer from Bowden cable stretch but this was soon rectified by the 368 chassis with a solenoid. I very much liked this chassis and found it to be very reliable.
The LOPT was the same as the Philips 210 series but in a different frock. The Mitsubishi CT200 was very reliable but when it finally threw in the towel it was very difficult to service with those vertical plug in boards. You needed a set of extension leads but by that time they were 12 years + and it was hardly worth the cost. The other make with the vertical plug in boards was Toshiba. The models were the original C81b and the C800 series. They had interconnecting square pegs linking both sides of the board and the only way to completely cure the problem was to unsolder the pegs and replace them with tinned copper wire. Job done! It was no good attempting to resolder them. They would bubble and spit! Everything looked faultless but you would have a repeat call within a few months if you did not rid the board of those links. Just a 30min job but that was the end of the problem. The later 2000 series from 1976 had a redesigned board minus the pegs! I never had a component breakdown with these 110 degree 18" and 20" models. Toshiba were always VERY helpful! Regards, John. |
28th Jul 2021, 5:09 pm | #93 |
Hexode
Join Date: Nov 2010
Location: Market Drayton, Shropshire, UK.
Posts: 486
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Re: What was the worst CRT TV to work on and why?
In the Dixion/curry's household there a few shockers but also very good set.
Shockers Finlux Peacock arcing inside the main electrolytic causing lots of Damage to power supply very bad connector to all sub panels causing intermittent colour Matsui 209 r 209t. these sets should never have seen the light of day very poor quality pcbs Matsui 1810. sound sub panel 6M/c was a nighmare very poor on off knob combined with volume control Good ones Matsui 219 really good set as goods or even better than tx100's 20r1 20t1 easy to work not many problems Derrick |
28th Jul 2021, 6:36 pm | #94 |
Dekatron
Join Date: Aug 2013
Location: Wigan, Greater Manchester, UK.
Posts: 9,433
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Re: What was the worst CRT TV to work on and why?
Leaving the trade in the very early 1980’s it appears I missed the really nasty sets.
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Frank |
29th Jul 2021, 10:08 pm | #95 |
Hexode
Join Date: Aug 2014
Location: Featherstone, West Yorkshire, UK.
Posts: 386
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Re: What was the worst CRT TV to work on and why?
I left the trade around the time of the G11, and went into my true love, the music industry.
One amplifier module from a "respected" German company constantly appeared on my bench, a simple 100W jobbie. Problem was, it would blow its output devices an any day with a Y in it. Despite complaining to them about the poor life expectancy, I received no feedback from them. I spent some time analysing the circuit, and found the "lop sided" short circuit protection made it oscillate wildly when driving a low impedance load. I sent them a large folder showing my findings, and my modification which made the amplifier stable. The answer I received just about says it all. "That is how it was designed" |
29th Jul 2021, 10:37 pm | #96 |
Moderator
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Re: What was the worst CRT TV to work on and why?
Their reply was perfectly factual, and without saying a word further, spoke volumes about how much they cared.
The correct response from you (to my way of thinking) would have been. "Ah, yes, thank you, that explains it. So you need a better designer then?" They obviously hadn't thought about what they'd said. Always take the high ground when you know you're right! David
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30th Jul 2021, 1:11 pm | #97 |
Octode
Join Date: Sep 2020
Location: Thetford, Norfolk, UK.
Posts: 1,743
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Re: What was the worst CRT TV to work on and why?
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30th Jul 2021, 10:21 pm | #98 |
Hexode
Join Date: Aug 2014
Location: Featherstone, West Yorkshire, UK.
Posts: 386
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Re: What was the worst CRT TV to work on and why?
No, we were not allowed to take the high ground.
The company MD and board of Directors instinctively knew service personnel were in the wrong before they had heard the question. They even came up with a brilliant new strategy; we were not permitted to utter the words NO FAULT FOUND under any circumstances. The unit was to be kept on test until the customer screamed at one of the directors, the customer would then be given a full refund - any age product. |
31st Jul 2021, 9:22 am | #99 |
Octode
Join Date: Apr 2005
Location: Peterborough, Cambridgeshire, UK.
Posts: 1,898
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Re: What was the worst CRT TV to work on and why?
My video engineer detested a recent repair failing or returning for a different fault, not that it happened very often as he was very thorough, he would put a note on all of the repair documents of older machines. A typical example would be "N.B slight wear to video heads ". As machines got older the list would increase or sometimes it would just state "N.B other wear". Another little trick was to repair the second fault be it the same symptoms as the original or not, soak test the machine and then release it as "No fault found". Often when making out the repair invoice these comments would be removed or amended as the shop staff often went through the repair invoice with the customer and said to me "how can we give someone a bill for an extensive overhaul and then state the machine is worn? Some of these "N.B s" read like a sermon ! "
Then someone bought him a mug with "NB wear" on it... Rich |
31st Jul 2021, 3:36 pm | #100 |
Tetrode
Join Date: Jun 2008
Location: Stratford upon Avon, Warwickshire, UK.
Posts: 80
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Re: What was the worst CRT TV to work on and why?
I would like to nominate the Grundig 5010 /6010 series for the following reasons:
1 They were very heavy. 2 Their British spares department were unhelpful. 3 Sales were even less helpful. The set itself was interesting, possibly the first with a thyristor line output stage and once you knew to change the gate chokes and capacitors for up rated parts they worked quite well. Re aligning the ultra sonic remote control with audio generator and oscilloscope could be time consuming and was a workshop job unless the set was in an upstairs flat! I had the large gray suitcase that contained all the parts Grundig thought might fail plus all those I knew failed, an essential for the back of the estate car when a Grundig was on the list of jobs. No problem with BRC 2000, 3000, 8000 etc, G11 was another good set and as an ITT dealer the CVC and Digivisions were no problem. I think I still have EL519 and EY 500 for the EMO in the garage.
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