Position of final anode connection on CRT - UK Vintage Radio Repair and Restoration Discussion Forum

Skywave · 4th Oct 2007, 10:14 pm

Reading the recent Post by Mikey405 - Best / Worst TV Awards - has prompted me to ask -

BRC 2000. Why - from a design viewpoint - was the CRT fitted upside down in the cabinet (EHT cavity at the bottom) ?

Just curious.

Al / Skywave.

ppppenguin · 4th Oct 2007, 11:01 pm

It wasn't on the 2000. The 3000 had that honour. Apparently it made pincushion distortion subjectively less visible. Neither the 2000 nor the 3000 had pincushion correction though the 2000 had space for it on the convergence panel. I fitted it to mine when I had one.

Steve_P · 4th Oct 2007, 11:25 pm

Jeff's right - it was the 3000 (and the 3500) set. As Jeff said, it was fitted upside down to correct Pincushion Distortion. This distortion was more common at the top of the screen, so to make it less visible to the human eye, the tube (and all the magnets etc) were fitted upside down.

They were the only sets to do this... I think!

Cheers,

Steve P

Welsh Anorak · 5th Oct 2007, 11:56 am

Hi
Yes - the 2000 had the tripler mounted onto the CRT final anode so it had to be the right way up. Did a later Thorn (8500 or a 9X00 series) have one upside down as well? And my mind's nagging me that a very early Hitachi colour set did as well.
Talking of odd EHT connectors, am I dreaming or was the A51-500X (20AX 20" as in the G11 and T20) made with the final anode on the top right side of the CRT?
Glyn

FERNSEH · 5th Oct 2007, 12:38 pm

Quote:

Originally Posted by Welsh Anorak

Talking of odd EHT connectors, am I dreaming or was the A51-500X (20AX 20" as in the G11 and T20) made with the final anode on the top right side of the CRT?
Glyn

It was.

DFWB.

Skywave · 5th Oct 2007, 6:19 pm

Quote:

Originally Posted by ppppenguin

It wasn't on the 2000.

Yes - I had a sneaky feeling when I wrote that that my memory was playing tricks on me.

It was a long time ago . . .

The set I am thinking of was a BRC / Thorn, all transistor, 17" screen (with quite rounded corners), four push-button-mechanical tuner on the lower RHS.
It's final demise was when the CRT neck coil ass'y. caught fire!

Anyone care to give my memory a jog? Thanks.

Al / Skywave

Steve_P · 5th Oct 2007, 6:24 pm

8000 Series sets. (8000, 8000A, 8500 etc). by the sound of it. Case of Design by Luck really.

Cheers,

Steve P

Dr-Watts · 5th Oct 2007, 6:38 pm

Quote:

Originally Posted by FERNSEH

It was.

DFWB.

The G11 wasn't, it was in the centre top - like any normal telly

I reckon I did more G11's than anyone my age LOL

Dr. Dave

Danny · 5th Oct 2007, 9:29 pm

Hi yes the twenty inch G11 did have the anode in the right corner on some models . but i only had about half a dozen 20" sets in the peak of G11 time . Danny

Welsh Anorak · 6th Oct 2007, 12:23 pm

Hi
Much as I hate to disagree with a man in a hat, I remember a G11 that set fire to its anode connector which was behind the LOP panel, mainly because the (earthed) lead had to be bunched up and had become snagged.
Glyn

Dr-Watts · 6th Oct 2007, 1:22 pm

Perhaps I never saw a 20 inch version then...

I stand correted

Dr. Dave

4th Oct 2007, 10:14 pm	#1
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Position of final anode connection on CRT Reading the recent Post by Mikey405 - Best / Worst TV Awards - has prompted me to ask - BRC 2000. Why - from a design viewpoint - was the CRT fitted upside down in the cabinet (EHT cavity at the bottom) ? Just curious. Al / Skywave.

4th Oct 2007, 11:01 pm	#2
ppppenguin Retired Dormant Member Join Date: Dec 2003 Location: North London, UK. Posts: 6,168	Re: BRC 2000 chassis It wasn't on the 2000. The 3000 had that honour. Apparently it made pincushion distortion subjectively less visible. Neither the 2000 nor the 3000 had pincushion correction though the 2000 had space for it on the convergence panel. I fitted it to mine when I had one.

4th Oct 2007, 11:25 pm	#3
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: BRC 2000 chassis Jeff's right - it was the 3000 (and the 3500) set. As Jeff said, it was fitted upside down to correct Pincushion Distortion. This distortion was more common at the top of the screen, so to make it less visible to the human eye, the tube (and all the magnets etc) were fitted upside down. They were the only sets to do this... I think! Cheers, Steve P __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

5th Oct 2007, 11:56 am	#4
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,918	Re: BRC 2000 chassis Hi Yes - the 2000 had the tripler mounted onto the CRT final anode so it had to be the right way up. Did a later Thorn (8500 or a 9X00 series) have one upside down as well? And my mind's nagging me that a very early Hitachi colour set did as well. Talking of odd EHT connectors, am I dreaming or was the A51-500X (20AX 20" as in the G11 and T20) made with the final anode on the top right side of the CRT? Glyn

5th Oct 2007, 6:24 pm	#7
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: BRC 2000 chassis 8000 Series sets. (8000, 8000A, 8500 etc). by the sound of it. Case of Design by Luck really. Cheers, Steve P __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

5th Oct 2007, 9:29 pm	#9
Danny Heptode Join Date: Jul 2003 Location: North Walsham, Norfolk, UK. Posts: 516	Re: BRC 2000 chassis Hi yes the twenty inch G11 did have the anode in the right corner on some models . but i only had about half a dozen 20" sets in the peak of G11 time . Danny

6th Oct 2007, 12:23 pm	#10
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,918	Re: BRC 2000 chassis Hi Much as I hate to disagree with a man in a hat, I remember a G11 that set fire to its anode connector which was behind the LOP panel, mainly because the (earthed) lead had to be bunched up and had become snagged. Glyn

6th Oct 2007, 1:22 pm	#11
Dr-Watts Heptode Join Date: Dec 2006 Location: Milton Keynes, Buckinghamshire, UK. Posts: 696	Re: BRC 2000 chassis Perhaps I never saw a 20 inch version then... I stand correted Dr. Dave __________________ Do you have the scope to be a TV repair man