Best CRT colour TV?

[Maarten]

Originally Posted by Heatercathodeshort

The 45AX series never focused correctly from new and appeared to have a poor red phosphor giving 'orange' reds. For some reason the 45 AX CRTs in Panasonic and JVC receivers were free from this problem. I can't recall a single model that produced poor quality pictures in the 70's/80's or 90's but of course there may have been a few that were a bit below the high standard but as I have stated before, customers never noticed and were more than happy with the results.

I think Panasonic and JVC used later variants of the AX45 series. The very first (presumably) 45AX was the A66EAK01X which was replaced by the A66EAK51X after a relatively short production run. That was probably for a reason.

[marsbar]

I have a Thomson 4:3 Black Pearl TV, 28" CRT. The nice thing is that it has a 16:9 function. The pitch and resolution is outstanding, also color reproduction.

I believe it uses the Sony technology, the dots are slightly more vertical dense.

I stayed with CRT for a long time, as flat screens did not do a good job in the beginning for color reproduction. CRT also hide some compression artifacts when MPEG2 was used at low bit-rate.

Also repaired my Bang Olufsen today, LX-2800. This has a Philips CRT tube, but the resolution is not as good as the Thomson.

I keep the TV's plugged out when I am not using them to expand life time.

[greg_simons]

Yup, philips k30 and kt3 for me, also loved the g6 and g8 but that's another era.

[hans]

Originally Posted by marsbar

I have a Thomson 4:3 Black Pearl TV, 28" CRT. The Also repaired my Bang Olufsen today, LX-2800. This has a Philips CRT tube, but the resolution is not as good as the Thomson.

This set uses the 45AX tube, which is as discussed above not the best. Your set probably also has the first generation of it.

[hans]

Originally Posted by Maarten

You are right that some Philips series had poor tube life, or maybe it was the tubes themselves. First generation 45AX seemed not too good, and depending on the chassis some 30AX tubes went duff as well (it seemed to me the K30 was worse than the K40 chassis, but no hard dat). I think the 2A and CP110 chassis with 45AX tubes didn't have a fantastic tube life (though not that bad compared to Telefunken and SEL tubes at the time - SEL also did contract manufacturing for Sony by the way), while the G110 chassis had a very good tube life.

I also noticed that the 30AX lasted longer in the K40. But that might be due to the poor quality of the first tubes. These tubes weren't in the K12 either. (I encountered a few of the K12s With the 30AX tubes, these were Swedish sets.)

The smaller tubes from TFK and SEL were better than the larger ones. I found the 26" 20 AX tubes from these manufacturers horrible.

[Clydeuk]

I always found the 22 inch Philips K40 ha.d a great picture, to my eyes it was better than the TX10 and TX100 and the K30. Whether this was the design or the fact that it was newer I don't know. The later 30AX tubes were definitely better than the early ones.

[Maarten]

30AX tubes were used in all K12i and K12Z sets (the chassis using earlier tubes were called K12 without a suffix). Mostly made in Sweden and Germany, I think. Dutch and Belgian production was already moving on to newer models.

[Nickthedentist]

Subjectively, some of the "best" CRT pictures I've seen have been on portable sets.

I can still remember being bowled-over by the image quality on my Hitachi CPT1473, Philips 16" KT3, and Philips NC3. And the ubiquitous Thorn TX9 portables also gave an amazingly vivid picture for the price.

N.

[MALC SCOTT]

The best picture from a portable set for me was the Philips KT2.

[stevehertz]

Originally Posted by Nickthedentist

Subjectively, some of the "best" CRT pictures I've seen have been on portable sets.

Well don't portables ie small crts have a head start when it comes to colour density and the fact that lines are all closer together? Also, proportionally you tend to view portables 'further away' that you do bigger sets, so again that helps with definition.

[ntscuser]

Originally Posted by stevehertz

Well don't portables ie small crts have a head start when it comes to colour density and the fact that lines are all closer together?

Not necessarily. Remember the Kuba Porta-Color with its awful cut-down shadowmask tube?

But in general I agree with you.

[mhennessy]

It's much the same point that I made back in post #8: viewing distance vs screen size (given that number of lines is fixed). With the added possibility of being able to see the shadowmask if you get too close...

And the added possibility of the shadowmask limiting the resolution (as the pitch doesn't tend to get appreciably finer with smaller domestic CRTs. Some combinations of shadowmask pitch and screen size actually require you to de-focus slightly to avoid moire patterns, ironically, though that is usually accounted for in the gun design... Likewise, larger screens also have a deliberately large minimum spot size to avoid the line structure becoming too obvious.

I have a lovely 9" Sony professional monitor on my bench (very cheap second-hand), but sadly it didn't have the "HR" CRT option, so at normal viewing distances I can see the shadowmask. Move back a bit, and it's fine. Superb picture, otherwise

BTW, what's "colour density"?

[Welsh Anorak]

Hi
It does come down mainly to the CRT fitted. A lot of Profilo 28" widescreen sets were sold under various names. The ones with a Philips tube gave spectacular pictures for a budget set with equally spectacular short life. Others were fitted with a Thomson tube - the pictures were truly terrible, soft, mushy with peculiar colours, even when new, and lasted for ages.
I was never keen on most Thomson tubes - the pureflat 32" needed an awkward software upgrade so the set didn't cut out while warming up - this required some SMD parts. Of course the easy option was to slightly increase the heater voltage.
Agreed - the A51-570X was a terrible tube, and any we bought ex-rental were glowing like light bulbs! Mind you, being a KT3 or CTX they were well worth re-tubing. And if you found one with a Matsushita tube you were very happy - great pictures for the life of the TV.
Glyn

[Maarten]

The spectacular short life will have been made more so by the crappy chassis overdriving the tube (33kV EHT looks even sharper than 30kV), so it really also comes down to the chassis maker not thinking beyond the basic appnote. This usually also manifests itself in a random faillure pattern instead of having only a few stock faults (but it may also have some stock faults).

[Welsh Anorak]

Hi
To be fair, the CRTs involved were the ESF versions so they did tend to fail prematurely in all sets - the ones in the Profilo sets were usually French which tended to fail sooner and more decisively than the German ones - no idea why. Mind you the third harmonic tuning capacitors used in those sets were very poor quality so the EHT could be anything from 22-30kV. When replacing then an EHT meter was a useful tool. To be honest, they were the main cause of receiver failure. We used 3kV types by Jaeger for reliability.
Glyn

[Maarten]

Indeed, they failed prematurely but I know of repairmen who changed the tuning capacitors in various chassis brands to slightly larger capacity ones and had decidedly less tube failures. Could be because of a somewhat lower heater voltage.

[Zelandeth]

For me the most natural looking picture I've seen on a domestic CRT set was on our old Mitsubishi CT-2023B (dated from 1984 if I remember right).

Very sharp picture, perfect convergence and very natural colours were the ticket. Sound wasn't half bad either.

Still have it sitting in a corner waiting to be resurrected one day.

[McMurdo]

When I lived at home we only really had 2 colour TV's after the Thorn 850 that my parents bought when they got married. I remember them both, (the tv's) and they were both Philips, and both would have been bought by Dad who's way was to demand 'give me the best you've got'. The first was a monster G26K521 (G8) which lasted from 1972 to 1983 (taken in part exchange) and the second a 26CS3880 (K35) which lasted from 1983 to 1999 (replaced still working). Both TVs had fantastic pictures and both had come from seperate engineer-owned independent dealers who had supplied them with their blessings. I'd have either of them today as my main TV (except neither of them would fit in the inglenook in my lounge) and they'd still outperform any LCD panel I've ever seen including these gargantuan HD devices which only have to be HD because they're so big!

[stevehertz]

Originally Posted by ntscuser

Not necessarily. Remember the Kuba Porta-Color with its awful cut-down shadowmask tube?

But in general I agree with you.

Actually no, I don't remember the Kuba Porta-Color with its awful cut-down shadowmask tube. I wasn't saying that 'every' portable set displayed better pictures than bigger sets. I was merely pointing out the physics of the situation, and that as a result of that, smaller CRTs/sets have a head start in terms of much of the criteria associated with the image quality of a colour set. I mean, if a portable is badly designed and has a bad picture as a result of that, then that's just how it is, but it doesn't change the laws of physics wrt colour tubes and how they are viewed/perceived by the viewer.

[Hybrid tellies]

Interesting thread this. Up until last September our main TV was a 21" Philips 4:3 Blackline 50Hz CRT NICAM stereo set which I bought new back in 1998 and it’s probably the best set that I have ever owned. It uses the Philips French built MD1.2E chassis, it has a fantastic picture, very bright, sharp but warm look to it with very good black level and picture geometry.

The sound is superb through its front facing coaxial speakers driven by a 10+10W amp and using Philips stereo enhancer with NICAM it was unbeatable. In fact it was so good I had to turn the bass down as you could feel it through the upstairs floorboards even at lower volume levels.
Thanks to my young son it got very heavy use with him watching the two BBC children's channels and CH5's kid’s programmes which started at 5am.

The only problem I had was the on/off switch failed three times. The third time it failed, as a temporary fix, I linked the switch out on the PCB and fitted an external 2 pole main switch. That was nearly 10 years ago

Under pressure from the family I finally caved in and replaced it with a new LCD flat screen set to end their endless complaints of not seeing the whole picture anymore which was very noticeable especially with sporting events.
As the tube is still good I just could not bring myself to recycle it, so I am now trying to rearrange my small and congested workshop so that it can sit and work alongside my 1980’s Ferguson 14” TX90 and 1970’s 19" Decca Bradford.