Bob Howe wants to know. What was the worst CRT TV to work on and why?

[FERNSEH]

The Sharp CS sets were truly terrible. Lucky for me I got wind how bad the sets were and didn't buy any for sale or rental.
The later DS models were OK though.
Looked after the many 25 and 28" Sharp TVs which preceded the CS. Good sets but I do remember having to repair one which defied logical servicing methods. Turned out to be a 2200uF capacitor in another part of the circuit. Might still have the servicing notes somewhere. Back in the 1990s I was still keeping a record of servicing procedures. Come the 2000s I couldn't be bothered doing anything like that, just had enough of the trade.
In the early days of colour there was the dreadful Decca CTV25 to deal with. The Pye CT70 dual standard colour set was bit difficult to work on if the EHT unit had to come out. Single standard 691 and 693 were good sets to work on.
No complaints with the G8, not so keen about the G9. Liked the G11.
The Philips G110 produced excellent pictures and superb NICAM sound but that power supply wasn't nice.

DFWB.

[IKC2E51R8]

I still have two of the DS Sharps, both 28" both working perfect, one of them has a subwoofer connection so the sound on it is excellent.

[Top Cap]

Originally Posted by Richard_FM

The Philips G11 has got a bad reputation in some circles for giving trouble & being hard to fix.

Same with the GEC sets with double printed boards, which I've heard being likened to technical school projects rather than professionally made.

I was once TLO at GEC and the answer I received from the technical boys in the labs at Slough was that one guy was responsible for PCB manufacture.
As you probably know, GEC used a copper build as opposed to copper etch, the copper being deposited on the board where required rather than removed from a clad board. The story goes that this one guy asked for a salary increase and this was refused so he left the company. He took with him the secret of 'copper adhesion', it is reckoned he applied his own process to the bare board before the copper was applied. His absence is why the copper traces left the board so easily until they researched more into what the pcb guy did. Well that's the story given to me and we had a lot of trouble with the 2114 due to not enough copper being deposited. This led to terrible hum bars and I was called to a shop in the midlands where a large number had the same fault. I tried everything, new bridge rectifier, changing smoothing blocks and finally took the set back to Slough. They reported the 'thin track' problem and arranged a recall of the sets.
Worst sets? The Phillips Mono that hinged out but if a previous engineer left a screw out of the hinge side then the whole chassis landed in your hands. I know of one engineer electrocuted by this set. The other one I did not like was the 8000 series where the Blue lateral was mounted down rather than up. To adjust it meant your hand was very close to the live heat sink of the power supply below. Funny though how Mazda tubes always showed crushing on Whites whilst still very young compared to Mullard.

[slidertogrid]

I liked the G11 but it is true that the early models had their problems. I went on the Len Briggs launch lecture. They stressed over and over how reliable the set was going to be and the lengths they had gone to to ensure this.
Early sets suffered badly with blowing the line output transistor, cured I think by a modified mains input panel. dry joints causing burn ups on the line board and the mechanical push button unit drifting after a year or so cured by replacement with the 'tip switch' unit. Then the red smoother started blowing the tube neck off, the frame IC died because of the holder and the yellow capacitors failed...
All of that said they were much better than some 20AX sets of the time, at least they worked when you unboxed them. ( Yes T20 I am looking at you!)
Later sets were much better and the early ones were fine once they had been reworked.
I had loads on rental and they went on for years and even sold well as a "cheapie" at 10 years old!
I have one as a bedroom set. It blew it's frame chip earlier this year and needed a bit of work in other areas but at least it is repairable, unlike the Ambilight thing that it replaced!

[Red to black]

We came across the G11 riveted capacitor problem only after they were a few years old, as we never bought them new.
I still don't think I ever saw a damaged crt because of this problem, maybe just lucky? it normally killed the BU on the line output board first.

The Sharp CS chassis was a bit of a culture shock at first! however a lot of problems on that chassis stemmed from dry joints on the Philips yoke assembly and scan coil pcb on the crt! I must admit this was my least liked chassis even though I did successfully repair quite a few.
Sharp Technical was an absolute must with the CS chassis! you had to follow them to the letter regardless of whether your meter told you otherwise!, and only use Sharp spares (take a bow Willowvale) mind you, they (Sharp) were spot on with advice even though we weren't Sharp dealers, I often wonder if they were just glad to have somebody/anybody try to repair this chassis?

[Red to black]

The only thing I disagreed about the Sharp CS chassis was their replacement policy, we sent a chassis back for exchange for a customer of ours at considerable expense I might add, and I duly got the factory re-worked replacement which I totally had to re-program and set up, fair enough!
Anyway this failed again after about 4 or 5 month down the line so we tried to send it back to Sharp. oh no! it only came with 3 months warranty! you what?? after all that expense? no, sorry only a three month guarantee on re-worked boards came back the reply!
I did repair it FOC myself in the end, and we never ever sent another chassis back to Sharp after that.

[Richard_FM]

I've heard some Bang & Olufsen sets can be tricky as they used a lot of non-standard DC circuits and a faulty component can cause chain reaction faults.

[toshiba tony]

I went on several Sharp courses. The GF\DF and the CS. Was told the Class d stages would be trouble free. Of course they weren't! Didn't they have an ic2 bus if I remember correctly. That caused us problems, we built the Pony prog unit that served us well. It was a doddle to use, the engineers who were younger could never master using it, but it did me well, and fellow old gits.

[Philips210]

ITT Digivision anybody?

Other conventional ITT sets were usually easy to service quickly and economically. The digivision I suppose was ahead of its time but seemed over complicated.

Much later on, there was the digital Fidelity set that used the ZX5000 chassis though that was reasonable.

Yes, the Sharp CS was a horrible chassis. I remember problems with the Class D audio o/p stage in particular.
Sony sets from the 1970s though good, always seemed more difficult and expensive to repair compared to say a GEC 2110, Philips G8 or BRC 3500.

Regards,
Symon

[its ur aerial]

I was in the TV Trade man and boy from 1972 till 2001, and some of the most unreliable sets were not necessarily, the worst to fix, G11`s were unreliable, but mostly easy to fix, and usually resulted in a very nice little earner
The ICC5 and the late Sharp chassis, there's no denying were unreliable and a nightmare to repair.

I was also not a big fan of the Thorn 3000 either, despite working for DER & RR.
But my hate list would include, the Phillips G9, Pye 205, Amstrad 2200, Fidelity`s of all types , but the piece de resistance must go to Mr Derek Tyne, and his pi poor effort that were mostly sold by Tesco in the late 70's.

At least Mr Sugar's (Mug Punters gear) looked the part.

Ken. G6HZG VMARS.

[toshiba tony]

I came into the trade just a few years before Ken and have similar memories of some of his sets. Notably the 3000/3500 and they weren't my favourite either. Never got to see a Tyne, but got to work on a few Philips K70's. Heavy on juice, good pictures but sods to work on. Why were Tyne so disliked?

[greg_simons]

Originally Posted by toshiba tony

Brilliant sets with their 116 degree tube. The Sony KV1810. People ran from them but we got them tamed. GCS's were expensive but once preventative repairs were carried out they went forever.

Never liked them but once you knew the multi step procedure to get them working they weren't too bad.
Greg.

[ms660]

Originally Posted by Philips210

ITT Digivision anybody?

Yes, I worked for an ITT dealer, I went on the engineers day's out (the lecture/course)

It was the writing on the wall for me.....and it came to pass.

Lawrence.

[slidertogrid]

Talk of the ITT digivision has reminded me anyone remember the Akrua portables that had the digital chips in them that corrupted at the drop of a hat. Freemans sold loads, a lot locally through the staff shop. A mate of mine would re- programme the chip which sometimes worked.
Talking of portables there was the Bush set available in various colours, most blew up under guarantee due to the two electrolytics in the power supply.
John Lewis sold them with a 5 year guarantee God help them!
Worst Pye ? CT200 MK1 with the low voltage focus tube. Had a picture size control on the front incorrectly labelled "Brightness"

[Red to black]

Re: Akura sets,
their CX22,26 ? range did use a double sided daughter board that had the ITT digi chipset, this was unreliable due to poor soldering, nearly every through board link needed de-soldering and reworking to achieve some reliability, the PSU wasn't great either, Akura technical up in Cumbernauld were brilliant however, even though we were not account holders.

The Fidelity ZX5000 chassis likewise also used a cut down version of the ITT digi chipset, ie. without using the digital audio parts of that chipset, I don't think I had any major problems on the digital side on these as the Psu was so unreliable it didn't last long enough to give us any, the ZX5000 must have been fairly short lived and I believe it sent Fidelity (Caparo Industries ?) into bankruptcy!

The Bush mentioned above were the Chinese Onwa versions (also made with a JVC! badge) and were downright dangerous as again the PSU was inherently flawed designwise and would have a propensity to overvolt, JVC (Steve Beeching) attempted to tame the beast with a series of modifications but as the design was inherently wrong they still were not reliable even after all mods were carried out, they just sort of faded away not long after.

[murphyv310]

Hi.
The Sharp CS & ICC5 still make me shudder with what we endured. Philips as well with Painter Chips, tubes and other problems.
The Samsung Slim Fit with convergence issues and line stage problems.
The last days of CRT were indeed not good and neither were the early days of LCD sets as well.
I'm glad I got out in 2006 to be fair.

[slidertogrid]

Originally Posted by toshiba tony

I came into the trade just a few years before Ken an dhave similar memories of some of his sets. Notably the 3000/3500 and they weren't my favorite either. Never got to see a Tyne, but got to work on a few Philips K70's. Heavy on juice, good pictures but sods to work on. Why were Tyne so disliked?

I only saw a few Tyne sets I can't remember working on them or what the faults were though. I cabinet had a bit of a home-made look to it ISTR?
I used to visit a local dealer weekly they had a huge amount of sets out on rental and I would go and buy a few G8s and Pye CT227s each week. They had a repair service where people could take their set and wait while they had a look if it was a simple fault it was repaired there and then if not they could leave it. they called it the repair "surgery". Their engineers did not like Thorn stuff at all. They would save up the sets for my visit. Usually a few 9000s awaited me. I took my Thorn silicon kit with me and sat for the morning putting them right. They would pay me with a couple of free sets usually ones they had written off and had been given. I got some real good stuff that way. One of the best was an Hitachi Instavision about 2 or 3 years old with a flat tube. I knew the local Hitachi dealer well.. All I had to do was give him the heater coil off the tube base (and a drink) and he got me a new tube from Hitachi.
I didn't particularly like the K70 but I had a loads in the late 1970s as a local shop was selling them off non working very cheap and second-hand sets were very sought after.
There was a massive 12 Ohm? Dropper on the back of the chassis if anything went wrong in the HT or line stage it could glow red hot and shatter. I bought a load of the replacements as supply could be a bit intermittent. As soon as a potential buyer heard the sound quality they were reaching for their cheque book! If you needed to change the tube it came out of the front so the chassis could stay in place that caught a few people out!

Another set I didn't like much was the late 823 varicap "electronic tuning" some sets gave good pictures but others were poor you could set the decoder up by the book and it looked ok but after not too long it had a slightly Hanover bars look to it again with critical tuning and patterning. Not for long though as the thermistor on the power board would burn a hole in the panel and shower shrapnel all over the back of the decoder panel as it failed. That usually converted them to monochrome!
Rich

[Red to black]

Samsung were a bit strange in that they could release fairly reliable models and then release an absolute dog both in their VCR and TV ranges, one TV set which we nicknamed the mouse due to the shape of its back never really resolved its PSU issues (ie. it would self destruct!) it went through various incarnations of Psu mod kits SMR chip etc., but never really fixed as they still blew up majorly.
Their SI1260 etc. vcrs suffered from dodgy diodes (1n4001 with high forward voltage drop under load only, they measured perfect!) which could give a range of problems depending on which combination had failed. we got that bit mostly sorted thanks to Samsung technical but we had a few where the deck mechanicals just wouldn't stay reliably timed up, even a complete deck change never fixed a few of these, this could have been the way the customers were using these, but even so the decks still shouldn't have been so willing to lose their timing.

The Samsung VIK320 range of vcrs was another with a propensity for its Psu you to overvolt often blowing the capstan motor up in the process, again inherently flawed and you could never really trust them again.

Samsung were capable of producing some good reliable feature rich products for a reasonable price but then go on to produce an absolute horror of a product every now and again.

[Radio Wrangler]

Originally Posted by Philips210

ITT Digivision anybody?

The Intermetall division of ITT made the chipset for ITT's digitally implemented TV baseband system. A multi-ADC device digitised either CVBS from the tuner/IF. It could also have Composite video, S-Video or RGB gated to it from external sources. The digitised stream also fed the teletext decoder.

Not just ITT, these devices turned up in Panasonic sets (TX25W3 in my case)

I wouldn't say they were the worst sets, they seemed quite good, but faults could be deceiving.

A faulty ADC gave a missing code so you got a fringe of drop-out black dots part way through a graded background.

A faulty NICAM chip shorted the supply when it found a valid Nicam signal. On the bench , it worked fine, plug in an aerial and off it went!

David

[Heatercathodeshort]

Interesting comments. I think most of the junk was produced in the 1990's and there was a lot of it. I played safe with Toshiba and never looked back. I had the PSU problem with the Samsung VCRs but to be fair to Samsung they replaced all the faulty VCRs with the latest model FOC.

Predictability is everything. providing easy access is designed into the chassis as most design faults can be easily rectified. The manufacturers were very good when it came to service problems.

The Sharp CS chassis was incredibly bad. I knew the licensee of the local tip and he could not understand why so many modern receivers were being dumped! Almost without exception they were all blown up Sharp CS or the Philips A10 with either software problems or a very short lived tube. Not a nice time for the trade. John.