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-   -   Ferguson 247T: huge console TV set. (https://www.vintage-radio.net/forum/showthread.php?t=119613)

FERNSEH 16th Sep 2015 12:37 pm

Ferguson 247T: huge console TV set.
 
4 Attachment(s)
I'm having a tidyup in the workshop. Last night I dug out this huge Ferguson 21" CRT console TV, model 247T. It's one of the first 21" CRT sets to be marketed in the UK, I'd reckon it was made in 1955. The HMV 1820 was the first 21" UK made set, that was 1952.
One thing that always puzzled me was how the CRT was installed in the set.
Then it dawned on me, the wood panel that the CRT is fitted on is slides into the top of the cabinet, you flip the whole assembly upside down and just push it in. Actually, it's not that easy.
A new safety glass is required, that's not too much of a problem for me, a local firm will cut a piece of 6mm glass anytime.
The truth is I'm not all that keen on the set, do I restore it, chop it up for spares, or alternatively is there anyone interested on taking over the restoration job.?
The only way to watch 405 in on a set like this one.

DFWB.

beery 16th Sep 2015 1:57 pm

Re: Ferguson 247T: huge console TV set.
 
So when you received it, it was atually a sub woofer with doors?
Every subwoofer should have door of course!

Andy

FERNSEH 16th Sep 2015 2:56 pm

Re: Ferguson 247T: huge console TV set.
 
Hi Andy,
It sure was, a great big fifteen inch speaker. It's now stored away in a safe place, upstairs above the shop.

DFWB.

Heatercathodeshort 16th Sep 2015 5:41 pm

Re: Ferguson 247T: huge console TV set.
 
I had the number of the bomb squad here David but I seem to have mislaid it..Might be as well to have them around when you refit that MW53-20 CRT..

247T. An absolute monster but very high gain with flywheel sync. My parents had a 236T in the mid 50's. 17" console without doors. A nice job if anyone is willing to take it on and quite straightforward overhaul wise. I hope it goes to a good home. J.
[PS If you have no takers David I thought it might make a trendy receiver if you suspended the CRT unit from the ceiling via chains and cup hooks and ran the wires down to the receiver chassis. At least it would give a bit more floor space. just a thought.]

FERNSEH 16th Sep 2015 5:57 pm

Re: Ferguson 247T: huge console TV set.
 
Quote:

Originally Posted by Heatercathodeshort (Post 786730)
[PS If you have no takers David I thought it might make a trendy receiver if you suspended the CRT unit from the ceiling via chains and cup hooks and ran the wires down to the receiver chassis. At least it would give a bit more floor space. just a thought.]

Hi John,
what a good idea! Rather like in the manner of that spherical shape JVC TV.
The chassis could be located well away from the suspended tube, a long cable run for 17KV though.

The MW53-20 is 23 inches from the faceplace to the the base.

DFWB.

Heatercathodeshort 16th Sep 2015 6:31 pm

Re: Ferguson 247T: huge console TV set.
 
I'm glad you like the idea David, You could screw four brass batten holders, one in each corner, some frilly shades and maybe a few carbon filament lamps.
It could then claim to be the first 'Dual Standard' receiver..

Seriously it would be a pity to see this scrapped. It is huge but I doubt if there is another one in the UK. Strange that many post war receivers are now rarer than pre war models. I guess the Murphy V114 is one of them. John.

FERNSEH 16th Sep 2015 8:49 pm

Re: Ferguson 247T: huge console TV set.
 
The set has a future. Restoration will start soon.
It's likely this set is the only example in existence. A major recapping job required of course and the complex flywheel system will receive special attention.
The line timebase employs a sinewave oscillator and the frequency and phase is controlled by a reactance valve which in turn controlled by a double-diode phase discriminator. The circuit works beautifully but only when high quality silver mica capacitors are used in the oscillator and reactance stages.
A similar circuit was employed in certain earlier Ferguson models and the later models 305T and 405T.

DFWB.

gec2110 17th Sep 2015 4:36 pm

Re: Ferguson 247T: huge console TV set.
 
Nice collection of sets there.
I noticed in the picture a Rigonda VL100.
Is that a working set?

FERNSEH 17th Sep 2015 6:46 pm

Re: Ferguson 247T: huge console TV set.
 
I can't remember what happened to the Rigonda. It may have been given away to another collector, or, it might be upstairs above the shop.
The Ekco console TV and one of the 14" GECs have already been rehomed. The 17" Ferranti was serviced last year and is working really well.
I'm not going to keep the dark cabinet Pam and the Pye CTL58.
The two sets I made the 440 mile round trip to mid Wales and back are the Philips 600A projection set and the Ekco TV138.
A home has been found for the big Ferguson.

DFWB.

Heatercathodeshort 17th Sep 2015 7:00 pm

Re: Ferguson 247T: huge console TV set.
 
Quote:

Originally Posted by FERNSEH (Post 786783)
The circuit works beautifully but only when high quality silver mica capacitors are used in the oscillator and reactance stages.

Hello David,
I surprising number of Ferguson fringe models used to turn up in London. They are the ones with the model number ending in an odd number.

The Flywheel line sync as you say works very well once you have replaced the .01uf's [I think they are from memory] in the discriminator circuit.

Guys used to twiddle the transformer in an attempt to lock the line. It never worked for more than a few days leading to customer frustration.

If I remember correctly you had to O/C the line sync feed often done by a small switch on the back of the line hold control.

After setting the user control mid way you adjusted the primary untill the line frequency just 'ran through'. The sync was then reinstated and the secondary core was adjusted to centre the picture within the raster. Once set up they performed as designed.

The LOPT is usually ok. The only other stock fault I can remember was breakdown of the scanning coil tag board to the core. It was simple matter to lift the cardboard strip and insulate it. The focus magnets used to become unglued causing weird picture centering faults, again a simple strip down and reglue.
Nice sets these Ferguson. John.

ukcol 17th Sep 2015 7:24 pm

Re: Ferguson 247T: huge console TV set.
 
3 Attachment(s)
In the 60s I used to own an HMV 1867 which was a slightly later set (1957) than the Ferguson 247T. The HMV used an identical chassis to the Ferguson 317T but had a completely different cabinet.

In about 1968 I gutted it and made a single standard 625/UHF set on the original chassis. Well it seemed a good idea at the time. :(

FERNSEH 17th Sep 2015 11:22 pm

Re: Ferguson 247T: huge console TV set.
 
2 Attachment(s)
Pictures of the chassis. There is some surface rust in places but otherwise it is in good condition, just needs a good clean.
That smoothing capacitor is the first component to be replaced.
The circuit design is a development of the 14 and 17" models, the 203T series, called the nine star chassis. For the extra power required for the 21" CRT the PY32 valve HT rectifier is replaced by a finned selenium metal rectifier. The reason for the change was to increase the HT voltage. The frame output valve is a PCL83 instead of the ECL80 used in the smaller sets.
The build date is confirmed as late 1955.

DFWB.

Heatercathodeshort 18th Sep 2015 7:52 am

Re: Ferguson 247T: huge console TV set.
 
Watch the position of the tuner unit valves David. I believe it is of German origin and the valves are reversed to the UK normal. The PCC84 is at the front and the PCF80 at the back..Smoke if you get it wrong. J.

Radio Wrangler 18th Sep 2015 8:13 am

Re: Ferguson 247T: huge console TV set.
 
Quote:

Originally Posted by Heatercathodeshort (Post 786730)
[PS If you have no takers David I thought it might make a trendy receiver if you suspended the CRT unit from the ceiling via chains and cup hooks and ran the wires down to the receiver chassis. At least it would give a bit more floor space. just a thought.]


Calls to mind Gilliam's film "Brazil" but he didn't have huge CRTs, just little tiddlers with fresnel lenses!

David

FERNSEH 18th Sep 2015 9:44 am

Re: Ferguson 247T: huge console TV set.
 
No Fresnel lenses for us. Better still if a 24" CRT removed from a KB Regina could be suspended from the ceiling. That'll look even more scary.

Getting back to the Ferguson. I just couldn't believe that set was not equipped with floor castors. Well in fact it was fitted with such items so I'll fit them with any out delay. It weakens the cabinet if it is dragged about too much without castors.
Hi John,
That's right, the two tuner valves are positioned with the PCF80 frequency changer at rear of the unit. GEC TVs were fitted with a similar tuner. The advantage of this type of tuner is that the outer control shaft rotates the turret drum and the inner shaft is the fine tuner.
It's a great big robust unit.

DFWB.

FERNSEH 18th Sep 2015 3:16 pm

Re: Ferguson 247T: huge console TV set.
 
1 Attachment(s)
Main smoother replaced by a NOS can of similar capacity, same diameter but slightly shorter.
The next task is to supply a limited current through the line output transformer windings in order to drive out any moisture.

DFWB.

FERNSEH 20th Sep 2015 4:57 pm

Re: Ferguson 247T: huge console TV set.
 
2 Attachment(s)
We all acknowledge that passing a small current through the line output transformer windings to drive out any moisture is a good idea. Well, the transformer in this set the EHT overwind has a resistance of 19Kohms therefore supplying 30 volts from a bench power supply will not warm the transformer by any significant amount. 30 volts will result in only 00158mA passing through the winding which will mean that the heating effect will be only 0.047 watt. That's not enough. However, apply 200 volts will result is 1.05mA through the 19000 ohm winding which is going to be just over 2 watts.
Four new wooden blocks have been made for the new cabinet castors.
Once these have been fitted it will be possible to move this heavy set about without any difficulty.

FERNSEH 21st Sep 2015 5:20 pm

Re: Ferguson 247T: huge console TV set.
 
1 Attachment(s)
It goes without saying there will have to be a major capping job done to this chassis, all the TCC waxies and Hunts capacitors are useless. Flashes and sparking going on inside the PCL83 frame and sound output valves, it was never a good valve anyway.
The screen grid supply to the PL81 line output valve has been disconnected and also the same valve's anode top cap. The grand plan is to connect the anode connector of the EY86 to chassis and as mentioned in my last post supply 200 volts or so across the overwind so as to warm up the transformer.

The chassis will be run in this condition for a considerable time and in the meantime I'm sure all sorts of exciting things will happen, bangs and flashes no doubt.

DFWB.

Heatercathodeshort 21st Sep 2015 9:46 pm

Re: Ferguson 247T: huge console TV set.
 
Quote:

Originally Posted by FERNSEH (Post 787477)
Four new wooden blocks have been made for the new cabinet castors.
Once these have been fitted it will be possible to move this heavy set about without any difficulty.

You think so! It might be a better idea to screw a large hook into the centre of the cabinet top and employ the services of my lorry crane!

It might be worth checking the goodness of that MW53-20. It is probably OK if not suffering from the Mullard partial heater short problem, almost as bad as Mazda's infamous heater cathode leak saga.

I have checked my tube stock David but I'm afraid you are on your own with this one. A CRM211 could be fitted but I suspect the chances of finding a good one is slim. Regards, John

FERNSEH 22nd Sep 2015 12:49 pm

Re: Ferguson 247T: huge console TV set.
 
Quote:

Originally Posted by Heatercathodeshort (Post 787760)
You think so! It might be a better idea to screw a large hook into the centre of the cabinet top and employ the services of my lorry crane!

Hi John,
don't need the crane, with the castors fitted the mighty cabinet can be moved around with ease.
I've left the chassis on the bench to "cook" so to speak and although the line output stage is inactive 33 volts negative is present at the grid of the PL81 so we know that the line oscillator is working.
The main HT line has risen to 242 volts.
I've checked the CRT for emission and I reckon it's capable of a reasonably bright picture.

This set will be displaying pictures soon.

DFWB.


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