Extinct or very hard to find sets (625 lines to 1990)

[Welsh Anorak]

That's slightly odd (post #120), as most of these used those dual concentric on/off - vol and contrast-brightness controls at the bottom. This has four controls at the top which is like the 2040 series colour, but also has a VHF tuner!
We have a late-ish 2000 series in the shop which we keep meaning to have a look at.

[Focus Diode]

I guess like Thorn with their later 1400s they utilised the same cabinets as the single standard equivalents.
Would be interesting to see what chassis the GEC dual uses. I guess the late '60s all valve 2000 series with the five position VHF tuner.

The front style rather reminds me of the 2028 colour sets.

[Studio263]

Originally Posted by Red to black

Philips must have spent an absolute fortune over the years

They claimed to be spending £450,000,000 a year on research in the late 1970s. That was a lot of money back then.

[dazzlevision]

Originally Posted by Focus Diode

It occurred to me on viewing the excellent 1976 drama, 'Bill Brand' (Network DVD) late dual standard GECs appear very hard to find nowadays, though a few Series 1 single standard versions have survived. I presume this will use the all valve 2000 series chassis? Looks to be a 20" model.

The set appears to be a Sobell 1063 (20") or 1064 (24"), which were available in a range of four different colour trims. There was an equivalent GEC set, with a more traditional cabinet trim: 2063 (20") and 2064 (24"). This is similar to the Bush and Murphy cabinet styles, with the advent of the "painted" Murphy TVs in the mid-60s.

The chassis will be the final GEC/Sobell dual standard all valve type (which is a development of the GEC 2000/Sobell 1000 series) where there is a single horizontal metal "chassis" containing two PCBs and the mains dropper is mounted on a bracket above the IF/sound/video/sync panel. The VHF tuner is a GEC/Sobell in-house development incremental inductance type, with five positions (2 x Band 1, 2 x Band 3 and 1 x UHF - IF pre-amp). The four pushbutton UHF tuner employed Silicon transistors.

[Welsh Anorak]

I've never seen this design before. I assume from the model number they were the very last ones to use this chassis and were concurrent with the Series One for areas that hadn't fully switched to 625.

[Synchrodyne]

Originally Posted by dazzlevision

Not just Thorn. Radio & Allied offered 405/625 mono sets with VHF/FM radio facilities. The final set with radio being a GEC 2017, I believe (and probably the Sobell equivalent 1017..?).
Radio Rentals also made mono d/std sets with VHF radio - right up to their 680 hybrid series.

Approximately in what year would the last of the dual-standard-plus-FM monochrome receivers have been made?

I imagine that the incremental cost of adding FM capability to a UK dual-standard monochrome receiver was a bit less than it had been for the 405-line only case. The VHF tuner requirement (i.e. with Band II as well as with Bands I & III) would have been essentially the same for both. But whereas the 405-only receiver would have required a change to a dual-mode (AM and FM) and usually dual-frequency (38.15 and 10.7 MHz) IF strip, such was already in place (with 38.15 and 6.0 MHz frequencies) for the dual-standard TV receiver. That assumes that 6.0 MHz was used as the FM IF, but I understand that that was usually the case.

On the other hand, once single-standard, UHF-only 625-line receivers arrived, adding FM would have been more costly. A separate FM front end would have been required, modified for 6 MHz IF output, and perhaps an additional IF stage. By then perhaps demand for TV-FM combinations had dwindled anyway.

Turning to possibly or probably now-scarce TV receivers from the period at interest, I should not be surprised if the Beovision 1600 24-inch monochrome model (625-only) fell into that category.


Cheers,

[dazzlevision]

Approximately in what year would the last of the dual-standard-plus-FM monochrome receivers have been made?

I would say in 1968, when Thorn Electrical Industries took over Radio Rentals. After that, Radio Rentals ceased to design and manufacture their own TV chassis and used Thorn designs, starting with the Thorn 1400 dual standard chassis.

[dazzlevision]

Originally Posted by Welsh Anorak

I've never seen this design before. I assume from the model number they were the very last ones to use this chassis and were concurrent with the Series One for areas that hadn't fully switched to 625.

I'm pretty sure that these dual standard sets were the last models to be produced by GEC/Sobell.

In the GEC/Sobell brochures I have, from the 1969-72 period, they offered dual and single standard large screen monochrome sets, to cater for the areas that weren't yet covered by three channel UHF/625/PAL transmissions (of BBC1, BBC2 and ITV), which commenced in November 1969. Most of the other UK TV manufacturers did the same.

[dazzlevision]

I'd have to agree with the earlier comments in this thread, that the 110 degree delta gun TVs of the mid 1970s didn't produce pictures as good as their 90 degree counterparts (not even those from B&O or Tandberg, in my opinion).

The pictures tended to be less sharp and the tubes soon exhibited poor focus, especially outside the central area.

I have a 26" Pye colour set fitted with the (110 degree delta gun) all transistor 747 "chassis". These sets appear to be very rare in collections nowadays.
This was the last Pye designed chassis. Subsequently, they adopted the Philips G11 chassis (following the cessation of the ten year "arms length" control Philips had over Pye, when they acquired a 70% controlling interest in 1967).

[Welsh Anorak]

Even rarer would be the 22" Pye fitted with the similar solid state chassis. Most were fitted with the conventional A56-120 and the 725 chassis but this had the 110 degree A56-140 CRT and the 741 chassis. I can't bring to mind another British made delta-gun 110-degree 22" set.
Again, the pictures were't as good as the 90-degree set (in my opinion) and the extra circuitry made these pretty unreliable.The last 90-degree 725s weren't too bad, but not Pye's greatest effort.

[dazzlevision]

Originally Posted by Welsh Anorak

Even rarer would be the 22" Pye fitted with the similar solid state chassis. Most were fitted with the conventional A56-120 and the 725 chassis but this had the 110 degree A56-140 CRT and the 741 chassis. I can't bring to mind another British made delta-gun 110-degree 22" set.

I've not seen a 22" Pye 110 degree delta gun set, but I do have the full Pye 731 to 741 chassis series service manual (ring binder version), so I'll check it out. Pye issued supplements listing all the models produced, so that should enable identification of any 22" 110 degree sets.

As to any other British made delta-gun 110-degree 22" sets, I did have a 22" set fitted with the Rank Z179 chassis (it was an export model, for the Irish market and so had UHF and VHF tuners fitted), fitted with a Mullard A56-140X CRT.

[dazzlevision]

22" Rank Arena Z179 chassis CTV

[neil29]

Originally Posted by dazzlevision

Rank Arena Z179 chassis CTV

Now there's a set I would like to find.


Cheers
Neil.

[dazzlevision]

For those unfamiliar with the construction of the Pye 731 to 747 (110 degree CRT) and 725 (90 degree CRT) chassis, here's a photo of it. The 725 is shown.

[Welsh Anorak]

I have the full service manual for the Z179 which was an odd mixture of designs. The PSU, IF and decoder was like the late A823, using an SL901 and SL918 while the output stage was more continental in design. I never knew they made a 22" one, the manual referring to the 26" version, of which I serviced one or two back in the day. They were the flagship Bush sets then, like the A816 mono. Anyone know why the chassis were prefixed A, Z and then T?

[Welsh Anorak]

The 22" Pye 110-degree was a fairly ugly beast with slider controls and a seven (I think) push-button tuner similar to the ITT and other European sets of the period.

[Synchrodyne]

Originally Posted by dazzlevision

I would say in 1968, when Thorn Electrical Industries took over Radio Rentals. After that, Radio Rentals ceased to design and manufacture their own TV chassis and used Thorn designs, starting with the Thorn 1400 dual standard chassis.

Thanks for that. The species, apart from being relatively rare, appears to have remained largely anonymous. I can find very few mentions in the literature, and no examples of actual circuits. There was passing mention of the BRC case in Wireless World 1963 October, and Spreadbury, in “Television Explained, Volume 1” devoted just over a page to it.

Somehow it is the kind of receiver that one might have expected Dynatron to offer, given that before the dual-standard era, it seemed to have paid quite a bit of attention to detail in its (405-only) TV-FM receivers. For example, the TV50, of the early 1960s had AFC not just for FM, but also for TV, obtained from the AM sound channel (using a discriminator that also appeared to double as an AM detector). But I haven’t seen any evidence that Dynatron participated in this little corner.


Cheers,

[Andy Doz]

Originally Posted by dazzlevision

For those unfamiliar with the construction of the Pye 731 to 747 (110 degree CRT) and 725 (90 degree CRT) chassis, here's a photo of it. The 725 is shown.

First set I ever repaired!

Loss of colour when warm. It was a cap by the thick-film.

I'm amazed I can remember that. It was 38 years ago!

[Welsh Anorak]

Talking of the sold-state Pyes, it appears the original 110 degree set needed 0.9 service calls a year whereas the final 725 90-degree sets needed only (!) 0.51 calls per year. This apparently put them in line with the Japanese manufacturers. I imagine Messrs. Sony, Hitachi and Toshiba had a good laugh at that 'fact'!

[Vectamart]

Originally Posted by neil29

Would the autovox sets have a 26" tube and a large white cabinet? because if so I had one over 20 years ago now and did manage to get something out of it (dodgy wiring). but like most things it got broken up and thrown away.

Cheers
Neil.

I vaguely remember Autovox being an in-house brand of Comet, as was the case with Solavox.