Philips 520 G8 variations - UK Vintage Radio Repair and Restoration Discussion Forum

System A · 2nd Jul 2007, 10:14 pm

Hi everyone

I have just obtained this early Phillips G8 model 520 (thanks Mike!) I have seen this model before but this one is unusual as it has the Phillips name above the button unit. My 534 model has the Phillips name in the usual place- below the speaker grill. Is my model a early one, I wonder.. anybody got any ideas?

Regards,
Gary

Dr-Watts · 3rd Jul 2007, 7:51 am

What a fantastic looking set !

Dave W

Mike Phelan · 3rd Jul 2007, 8:41 am

The G22K520 was the first set with the G8 chassis, and early production ones had a (dreadful) sub-panel on the chroma board because the TBA530 had not appeared yet.

Later changes were L-shaped heatsinks replacing the finned ones on the LOP transistors, BT116 instead of BT106 in PSU, BRY39 instead of BR101 for frame osc, ZTX33 for TAA550 varicap stabiliser.

HTH

Welsh Anorak · 3rd Jul 2007, 12:36 pm

Hi
I've never seen one with the name there - and the pictures in the manual have 'Philips' in the usual place, so I suspect it's a very early production one. As the panels probably aren't all original the best place to find a date is stamped on the inside of the cabinet.
If Mike's favourite RGB sub-panel was present it'll undoubtably have been swapped for a later version (unless the owner liked drifting greysacle!) - for once that won't be to the detriment of the set! I imagine one with a sub-panel will be very rare now....
Hope we'll see a picture on it soon!

Glyn

Mikey405 · 3rd Jul 2007, 4:54 pm

Quote:

Originally Posted by Mike Phelan

The G22K520 was the first set with the G8 chassis, and early production ones had a (dreadful) sub-panel on the chroma board because the TBA530 had not appeared yet.

Later changes were L-shaped heatsinks replacing the finned ones on the LOP transistors, BT116 instead of BT106 in PSU, BRY39 instead of BR101 for frame osc, ZTX33 for TAA550 varicap stabiliser.

HTH

Hi everyone.

Here's one of those boards with the sub-panel on...

From Mike.

Welsh Anorak · 3rd Jul 2007, 5:00 pm

And I suppose you're PROUD of giving everyone nightmares, then, are you??!

Mike Phelan · 4th Jul 2007, 8:15 am

I thought I had done my bit by binning quite a few of them.

One of the problems is that the regulation of the supply to this panel needs to be very stable indeed or the base currents of the video OP transistors wander all over the place.

We used to stick a heatsinked BFY50 and zener on a tagstrip to make a series regulator.

Interested if anyone has ever seen one like this!

Welsh Anorak · 21st Jul 2007, 2:17 pm

Hello!
Just rummaging as I do and here's the September 1970 copy of RER Service Engineer announcing the new G8 chassis. And the very early production model pictured does indeed have the 'Philips' name above the controls.

It also mentions everyone's favourite sub-panel, saying the missing IC 'should be available in six months' time'

So now you know!

Glyn

System A · 21st Jul 2007, 7:27 pm

Hi Glyn thanks for that information , i thought my set must be an early one . Is there any change that you could show us that article ? . Regards . Gary.

Welsh Anorak · 23rd Jul 2007, 2:01 pm

Hi there
Your wish is my command! However, I can't reduce the quality enough to get under the size bar, so PM me your e-mail address and I'll send it to you.
I didn't realise the G8 was as early as 1970.
I notice at the end it says 'the company anticipate the G8 will last for five years or so.' Do they mean the set or the production run? I'm really not too sure!

Glyn

2nd Jul 2007, 10:14 pm	#1
System A Pentode Join Date: Feb 2006 Location: County Durham, UK. Posts: 234	Philips 520 G8 variations Hi everyone I have just obtained this early Phillips G8 model 520 (thanks Mike!) I have seen this model before but this one is unusual as it has the Phillips name above the button unit. My 534 model has the Phillips name in the usual place- below the speaker grill. Is my model a early one, I wonder.. anybody got any ideas? Regards, Gary Attached Thumbnails

3rd Jul 2007, 7:51 am	#2
Dr-Watts Heptode Join Date: Dec 2006 Location: Milton Keynes, Buckinghamshire, UK. Posts: 696	Re: Phillips 520 G8 What a fantastic looking set ! Dave W __________________ Do you have the scope to be a TV repair man

3rd Jul 2007, 8:41 am	#3
Mike Phelan Dekatron Join Date: Nov 2003 Location: Near Leeds, West Yorkshire, UK Posts: 4,609	Re: Phillips 520 G8 The G22K520 was the first set with the G8 chassis, and early production ones had a (dreadful) sub-panel on the chroma board because the TBA530 had not appeared yet. Later changes were L-shaped heatsinks replacing the finned ones on the LOP transistors, BT116 instead of BT106 in PSU, BRY39 instead of BR101 for frame osc, ZTX33 for TAA550 varicap stabiliser. HTH __________________ Mike.

3rd Jul 2007, 12:36 pm	#4
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,927	Re: Phillips 520 G8 Hi I've never seen one with the name there - and the pictures in the manual have 'Philips' in the usual place, so I suspect it's a very early production one. As the panels probably aren't all original the best place to find a date is stamped on the inside of the cabinet. If Mike's favourite RGB sub-panel was present it'll undoubtably have been swapped for a later version (unless the owner liked drifting greysacle!) - for once that won't be to the detriment of the set! I imagine one with a sub-panel will be very rare now.... Hope we'll see a picture on it soon! Glyn

3rd Jul 2007, 5:00 pm	#6
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,927	Re: Phillips 520 G8 And I suppose you're PROUD of giving everyone nightmares, then, are you??!

4th Jul 2007, 8:15 am	#7
Mike Phelan Dekatron Join Date: Nov 2003 Location: Near Leeds, West Yorkshire, UK Posts: 4,609	Re: Phillips 520 G8 I thought I had done my bit by binning quite a few of them. One of the problems is that the regulation of the supply to this panel needs to be very stable indeed or the base currents of the video OP transistors wander all over the place. We used to stick a heatsinked BFY50 and zener on a tagstrip to make a series regulator. Interested if anyone has ever seen one like this! __________________ Mike.

21st Jul 2007, 2:17 pm	#8
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,927	Re: Phillips 520 G8 Hello! Just rummaging as I do and here's the September 1970 copy of RER Service Engineer announcing the new G8 chassis. And the very early production model pictured does indeed have the 'Philips' name above the controls. It also mentions everyone's favourite sub-panel, saying the missing IC 'should be available in six months' time' So now you know! Glyn

21st Jul 2007, 7:27 pm	#9
System A Pentode Join Date: Feb 2006 Location: County Durham, UK. Posts: 234	Re: Phillips 520 G8 Hi Glyn thanks for that information , i thought my set must be an early one . Is there any change that you could show us that article ? . Regards . Gary.

23rd Jul 2007, 2:01 pm	#10
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,927	Re: Phillips 520 G8 Hi there Your wish is my command! However, I can't reduce the quality enough to get under the size bar, so PM me your e-mail address and I'll send it to you. I didn't realise the G8 was as early as 1970. I notice at the end it says 'the company anticipate the G8 will last for five years or so.' Do they mean the set or the production run? I'm really not too sure! Glyn