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Forum 141

A 25" K-B colour receiver?

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ntscuser
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From PTV October 1966:

Forum 142

As far as I know K-B never marketed a 25" colour receiver in 1967. Their first colour set I think was a 19" dual-standard model produced in 1968 and their second was a 22" single-standard model produced in 1969.

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Posted : 20/10/2016 10:06 pm
Till Eulenspiegel
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It might well have been possible that a 1965/66 KB development colour receiver was similar to the CVC1 except for the method of EHT generation which most likely was by means of a 25KV EHT winding on the line output transformer.

Thorn-AEI Mazda colour CRTs were made with the assistance of the RCA.

Till Eulenspiegel.

 
Posted : 21/10/2016 10:54 am
ntscuser
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I suspect it was a rebadged version of this Graetz set made by parent company ITT for the German market:

http://www.radiomuseum.org/r/graetz_burggraf_color_1045.html

Would be amazing to find one with a K-B badge on it!

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Posted : 21/10/2016 3:58 pm
PYE625
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ntscuser said
I suspect it was a rebadged version of this Graetz set made by parent company ITT for the German market:

http://www.radiomuseum.org/r/graetz_burggraf_color_1045.html

Would be amazing to find one with a K-B badge on it!  

And it looks a nice smart set too. Interesting to see a GY501 and no PD500 shunt stabiliser in the EHT compartment. I also wonder if X-rays would escape through all those holes....duno_gif

To understand the black art of electronics is to understand witchcraft. Andrew.

 
Posted : 21/10/2016 5:51 pm
Alastair
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Oh--I remember Those horrors!

There was a company that assembled these things--Looked/layout like CVC5, EHT by Overwind and GY501 in the cage, no X-Ray shielding as none needed (Only need that with Shunt-Regs).

Had the name, 'Antur' on the front, but had wooden case, sorta like a primitive CVC5, just basic looking, early 6 push-button tuner--and marketed a lot later than '68 Thats for sure!

I think they were sold here in around '74. An awful lot of 'em had 'Issues' shall we say!

In the mid 80's I had one in for repairs--only dry joints and dodgy PCL805 as it had been Altered for a proper 240V supply with the addition of a buck-transformer in the case behind control-panel, it was a second set and not used much...

--It worked reasonably well as I recall....

Mods note: post edited to remove personal references and unsubstantiated claims. These are NOT permitted - please read the site rules with particular reference to rule 5.

 
Posted : 21/10/2016 8:40 pm
Till Eulenspiegel
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Looking at the valve line-up of the Graetz CTV reveals that separate line output and EHT generator valves are employed. The PL509 performs the latter function.  EHT regulation by controlling the current through the PL509, a system that serves to get rid of that nasty PD500 shunt stabiliser valve.  It's likely one of the PC92 triodes is used in the EHT control loop.

I can't ever remember this Graetz CTV being sold as a rebadged KB. 

In the 1960s the English and German ITT companies were independent of each other, rather like Ford of Britain and Ford of Germany were during those times.

 

Till Eulenspiegel 

 
Posted : 21/10/2016 9:09 pm
PYE625
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Alastair said
no X-Ray shielding as none needed (Only need that with Shunt-Regs).

I did wonder as I have seen pictures of early American colour receivers with just the EHT rectifier, no shunt valve and no x-ray shielding either.

To understand the black art of electronics is to understand witchcraft. Andrew.

 
Posted : 21/10/2016 9:10 pm
PYE625
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Till Eulenspiegel said
Looking at the valve line-up of the Graetz CTV reveals that separate line output and EHT generator valves are employed. The PL509 performs the latter function.  EHT regulation by controlling the current through the PL509, a system that serves to get rid of that nasty PD500 shunt stabiliser valve. 

 This would seem a much better way of doing things rather than crudely shunting down the EHT directly. No wonder the poor lopt's suffered.

To understand the black art of electronics is to understand witchcraft. Andrew.

 
Posted : 21/10/2016 9:14 pm
Till Eulenspiegel
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The only saving grace for the shunt stabiliser valve is that a constant load is applied across the EHT supply.  At zero CRT beam current the shunt tube draws max current, typically 1.2mA and as the current through CRT increases the current though the shunt tube is backed off in proportion to maintain the constant loading. The suggested EHT stabilising system in the Graetz CTV works on the principle at zero beam current the EHT voltage will be a max value and so the current in the PL509 will be reduced accordingly by the stabilising loop. Conversely,  when the CRT beam current increases the PL509 will required to deliver more power to keep the EHT constant.

Wasn't something like this type of EHT stabilising system employed in B & O CTVs?

Till Eulenspiegel.

 
Posted : 21/10/2016 10:30 pm
ntscuser
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Till Eulenspiegel said
I can't ever remember this Graetz CTV being sold as a rebadged KB. 

I wasn't suggesting it was but according to at least two independent reports K-B did show a 25" pre-production receiver at the Earls Court Show. If they developed it themselves it's extraordinary that they made no attempt to market it later. If they didn't then they must have borrowed one from another manufacturer, Graetz being the obvious source.

K-B would not have been alone in deceiving the public in this way, at the same show Philips tried to pass off a continental K6 as a British pre-production model. (There was no similarity between the continental K6 and British G6). I think that Earls Court used System-B for colour demonstrations that year in any case so there was little advantage in using a set designed specifically for the UK market.

There's another possibility that K-B simply tried to pass-off a dummy B&W receiver as a future colour set. That would at least explain the supposed extraordinary slimness of the cabinet.

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Posted : 22/10/2016 3:46 am
ntscuser
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PYE625 said
I did wonder as I have seen pictures of early American colour receivers with just the EHT rectifier, no shunt valve and no x-ray shielding either.  

I've seen a close up picture of the GY501 in the Graetz chassis and the lower half of the valve is shrouded by a very thick screen.

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Posted : 22/10/2016 3:50 am
Alastair
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A note to the Moderators about earlier now edited post, seeing I'm now on 'moderation' and Not for publication--

The 'Antur' locally assembled CVC5 type set--Did go on fire. This is fact. I saw the results of this, I also worked with a feller who worked for the guy who built these sets from imported German 'kits'.
--Both parties are now sadly long gone. I maybe shouldn't have mentioned names.

The reference to safety should remain IMHO, should anyone ever come across an ANTUR CVC5 type set, and be unaware of the sets problem....

 
Posted : 22/10/2016 8:41 am
PYE625
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should anyone ever come across an ANTUR CVC5 type set.......(say's Alistair above)

I would dare say that is unlikely....but boy, would I be excited if I did !! grin_gif

To understand the black art of electronics is to understand witchcraft. Andrew.

 
Posted : 22/10/2016 8:55 am
Cathovisor
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Alastair said
A note to the Moderators about earlier now edited post, seeing I'm now on 'moderation' and Not for publication--

The 'Antur' locally assembled CVC5 type set--Did go on fire. This is fact. I saw the results of this, I also worked with a feller who worked for the guy who built these sets from imported German 'kits'.
--Both parties are now sadly long gone. I maybe shouldn't have mentioned names.

The reference to safety should remain IMHO, should anyone ever come across an ANTUR CVC5 type set, and be unaware of the sets problem....  

Well, first of all Alastair, you're NOT on moderation so I fail to see what you're complaining about. You've had a post edited, that's not the same thing.

No, you should NOT have mentioned names. Although you can't defame the dead, nonetheless we have to exercise caution and if the families of the persons concerned were to read it, they may take exception. Similarly, saying what you have about the sets without publishing corroborating evidence puts us in a very difficult situation and that's why it was removed. I doubt any of the mod. team knew about the history of the sets in question (I certainly didn't) and so again, we have to exercise caution.

I would also venture to suggest that any surviving sets are unlikely to be left running for the periods of time they were when in normal domestic service and that equally, they are unlikely to be left unattended which sensibly, no piece of vintage equipment should be anyway.

Finally - if you have a problem with moderation here, PM a mod about it - DON'T do it in public.

 
Posted : 22/10/2016 9:48 am
Till Eulenspiegel
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Many Forum members will have seen or have knowledge of the imported "Comb Color" TV set. It was similar in construction technique to the UK made CVC5, the main difference was the use of a 25KV winding on the line output transformer instead of a tripler for EHT. There was many other minor differences in the Combi Color design. Perhaps the Antur color TV was similar.

Till Eulenspiegel.

 
Posted : 22/10/2016 10:04 am
Till Eulenspiegel
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The Welsh word Antur means Adventure or Venture.
Till Eulenspiegel.

 
Posted : 22/10/2016 10:10 am
malcscott
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I can remember working on these Antur sets in the early seventies.

 
Posted : 22/10/2016 10:12 am
colourmaster
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Hi everyone
When i started in the trade way back in 1978 where i worked they had a junk room full of these combi color sets .
They all had burnt out lopt's . the chassis did look a bit like the cvc5 .
Regards .
Gary.

 
Posted : 22/10/2016 11:09 am
itmog57
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I remember these sets, But I could never remember the name. (Been trying to for years. Google was NOT my friend), "ANTUR". Thanks for that Alastair.

BINNS started to sell them, must have been 1974 ish. It was in the days when CTV's were in short supply, so any TV to sell would do.

They looked like a cheap imitation of the ITT CVC5. If you looked at the slot for the Colour/Tint controls you could see the 3 layers of Plywood. Very poor finish. Taking the back off was the shock. It It did look like a CVC5, it really did. There were a few minor differences, The convergence unit looked the same. They sold like hot cakes as they were a lot cheaper than the ITT. Didn't see any come in for repair, so they must have been reliable. One of the Engineers got one as he couldn't afford the genuine ITT. And he loved it. (Wages for a fully qualified engineer was about £35 a week then)

I would like to know some history of the company that made them and how they got the chassis. Was it possible the chassis was imported then put into a local made cabinet. Or was it Eastern Block clone. (Regonda/Vega were making inroads at the time with small portable TV's and Radiograms, (Loved the one with motorised Auto Tune and a very smooth tuning knob, which you could spin and it would move across the dial in one go. Ahh Memory's))

Would love to find an ANTUR today. Or any 26" CVC7/8/9 come to that. (The ones with all sliders and the square channel buttons with tuning knob on the right hand side)

Sigh!! I Wish.

Ivor

 
Posted : 22/10/2016 11:35 am
Alastair
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Ah--My mistake, During my reply earlier, (Which would have been somewhat different if I thought it had gone instantly live),-- there was a system-message to say that my posts needed admin approval...

Thought that was the Moderation......

Yer Live and Learn....

As to these CVC5 pretenders, I think the 'Combi' version was somewhat better as I recall, the Antur not being very nice at all, either in finish or electrically....

Ivor--

If I see any CVC5-9 chassis sets I'll grab it for you. Since January Ive found a Thorn 1500, a GEC bow-front from mid/late 50's, a G11, a Sony 9-90, and a Thorn Ultra 405 line portable...

You Never Know! 

 
Posted : 22/10/2016 7:47 pm
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