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-   -   Alba TC1525 G6 Dual Standard. (https://www.vintage-radio.net/forum/showthread.php?t=157089)

MickMcmichael 5th Jun 2019 8:28 pm

Alba TC1525 G6 Dual Standard.
 
5 Attachment(s)
Now I could be being a little premature here. I haven't even switched this set on in 13 years and I'm not yet sure how quickly it will progress when I get started. Updates could be slow in coming so please bear with me.

This initial posting is to outline the recent history of the set and to explain what's likely to be involved.

I always wanted a G6 in my collection and one came up for sale during the summer of 2006. It was advertised as "working but no picture - just pink". The seller posted pictures of a blank pink raster.

Considering the prices they fetch now, I reckon I got a bargain at £160 which when you think about it is only about 16 delivered take-aways. And that line scan smoke stack unit can get hotter than a vindaloo!

A friend picked it up for me on his way back from London a day or two after auction end. The set came with its legs (not in these pics) and a spare IF board. There's no back cover so the set has been stored for these past years very carefully with thick foam behind the tube base.

I tried the set the same day as it was delivered and I obtained a bright pink raster as described. The brightness control had no effect. I wondered why the set came with a spare IF board and I quickly discovered why. The system switch (on the board) had been removed and some extremely low tech bodgery had been soldered in its place to make it 625 only. What a mess it is!

I can only think that someone got something very very wrong when doing this and the dreadful state of the bodgery is probably the reason for the pink uncontrollable raster.

So I've got a spare board with original coloured wires attached and still soldered to the printed side. The trouble is, the wires attached to the spare board aren't the same colours as the wiring loom in the set that I have. As the set has been bodged around the IF, I shall have to trace each wire back via the circuit diagram to the replacement board which has what looks like a good system switch in place.

But first I must see if that pink old raster is still available some 13 years on. It's going to be a bit like turning on the harbour lights; will they or won't they? I'll find out soon enough in the next day or so!

So, if there's any G6 maniacs out there, watch this space and if you can offer any tips then please don't hesitate!

The last time I worked on one of these was circa 1976. I replaced a PD500 and vacated the customer's premises and over the garden fence to my Hillman Minx quicker than David Hemery over a set of hurdles!

More soon.....hopefully! :wave:

1100 man 5th Jun 2019 10:16 pm

Re: Alba TC1525 G6 Dual Standard.
 
I'll be following this with great interest-: I've never been lucky enough to cross swords with a G6- they were all long gone when I started poking about with TV's!

I had always assumed that they would all have been Philips branded, so seeing an Alba one was a surprise.

Good luck with the restoration!

All the best
Nick

Richard_FM 5th Jun 2019 11:01 pm

Re: Alba TC1525 G6 Dual Standard.
 
Quote:

I had always assumed that they would all have been Philips branded, so seeing an Alba one was a surprise.
While Alba mostly used Thorn based sets, they also rebadged the Philips G8.

AC/HL 5th Jun 2019 11:05 pm

Re: Alba TC1525 G6 Dual Standard.
 
And the 1500, I have an Alba service manual.

slidertogrid 6th Jun 2019 8:08 am

Re: Alba TC1525 G6 Dual Standard.
 
Hi Mick
It's good to see the G6 underway at last! I repaired a few back in the late 1970's and to be honest I didn't like them much, compared to the GEC and Pye D/S sets I thought they were a bit of a complex dinosaur ! You couldn't easily swap a panel to prove a point and a valve decoder? Only Philips...
Good luck with it! I shall phone you every day to make sure you haven't gone mad.. I have the number for the men in white coats on speed dial...

:thumbsup:
Rich.

Restoration73 6th Jun 2019 8:38 am

Re: Alba TC1525 G6 Dual Standard.
 
I have an Alba here, 24" using Philips 230 (210) d/s chassis.

Tazman1966 6th Jun 2019 5:45 pm

Re: Alba TC1525 G6 Dual Standard.
 
An extremely rare set I would imagine. Good luck with it. I'll be following this with interest.

MickMcmichael 7th Jun 2019 4:22 pm

Re: Alba TC1525 G6 Dual Standard.
 
2 Attachment(s)
Well I couldn't believe this. After 13 years of storage square one mas been maintained!

I gave everything a visual inspection and then slowly wound it up on the variac, a quick abracadabra and a tap on the cabinet with a screwdriver and hey presto - a pink raster!

Actually the brightness control does have an effect and the brightness level will occasionally trigger the relay on the tube base and produces a slightly less pink raster.

All well and good so far. The next thing will be to put a plan into action to change the bodged up IF panel for a complete one.

Pinch nostrils and jump....here we go. It may take a while!

Welsh Anorak 7th Jun 2019 5:16 pm

Re: Alba TC1525 G6 Dual Standard.
 
The colour / B&W relay should do just that, so the fact that it's clicking at all suggests something very odd's at work. I think I'd check the supply lines - there are a couple of 12v LT lines stabilised by VDRs, so not very hi-tech! Also there's a -120v line (from memory) which uses a small red BYX10. If these are OK, then I suspect things are indeed amiss, especially around the PFL200.
I liked the G6, mainly because it was the first set I got to grips with, and because of the superb pictures they give - especially the dual standard for reasons I can't understand. One good thing is that the chassis easily comes out with only a couple of wires to unsolder. Replacing the IF strip will be exciting, but hopefully the manual will help - the location of those wires is fairly well drawn.
I don't think this set will ever be dual-standard again, but it certainly will be great to get going.

MickMcmichael 7th Jun 2019 5:23 pm

Re: Alba TC1525 G6 Dual Standard.
 
Yes I was aware of the change of hue with the relay Glyn. Unfortunately I don't actually have a proper manual. I'm working from circuits out of the Newnes 67/68 book which only basically shows circuits in small blocks.

The bodgery on the IF and around the PFL200 is severe and could well be causing many of the problems. It's sure gonna be fun!

Mr Hoover 7th Jun 2019 5:41 pm

Re: Alba TC1525 G6 Dual Standard.
 
There was a series of articles
about them in Practical TV
"Renovating the Rentals"
series..Starts in the July 1973
issue when they were relatively
modern!
Can be downloaded here.
https://www.americanradiohistory.com...n_Magazine.htm

MickMcmichael 7th Jun 2019 5:46 pm

Re: Alba TC1525 G6 Dual Standard.
 
What a great site. Many thanks for that.

I was going to trawl though all my TV magazines to find that series of articles. I couldn't remember which year.

Cheers! :beer:

Welsh Anorak 8th Jun 2019 12:17 pm

Re: Alba TC1525 G6 Dual Standard.
 
I do have a manual, but I also have a very sick G6 that I WILL do one day!
I could scan and send you the relevant page if you can't find one.

MickMcmichael 8th Jun 2019 12:32 pm

Re: Alba TC1525 G6 Dual Standard.
 
Thanks Glyn for the kind offer.

I've found the article in Television from 1973. It shows the IF board and the various connecting wires which is a good help. If I find I need anything else specific which isn't covered in the article I'll let you know.

Regards,

Mick. :thumbsup:

Mike Phelan 8th Jun 2019 3:14 pm

Re: Alba TC1525 G6 Dual Standard.
 
Well done, Mick.
The best G6; much better than the later single-standard ones and an excellent set if all the umpteen presets are correctly set up and everything else works.
Make sure you put the later desaturation choke with the larger ferrite core on the line output stage.

Heatercathodeshort 8th Jun 2019 4:43 pm

Re: Alba TC1525 G6 Dual Standard.
 
Yes the dual standard chassis did give a much better picture and were more reliable compared with the later single standard models but why? It should have been the other way round. I was 'broken in' with the G6 chassis and must admit, everything seemed easier after that!

I used to buy clean ex rental models and they made excellent reconditioned sales. I set the boost voltage just high enough to give sufficient width and this calmed down the line output stage and improved reliability vastly.

I did have a huge amount of trouble with a G22K511 22" single standard. It looked almost new when I obtained it, suspiciously so...

It would randomly burn out the purple desaturation choke [L5515?] filling the workshop with a sour stench. I replaced everything but it still did it. There was no answer to it and I eventually broke it up for spares, LOPT tube etc.

Overall they were a very good chassis and gave one of the best pictures of the day. J.

MickMcmichael 8th Jun 2019 8:08 pm

Re: Alba TC1525 G6 Dual Standard.
 
5 Attachment(s)
The old IF has gone and left a black hole in the chassis. The replacement board is poised to go in after some much needed rest and sleep.

Note the trapped black and orange lead at the bottom of the chassis. I noticed this the other day and checked to see if there was a short to ground. There wasn't but I had to loosen the screws at the bottom to release it. It was obviously there from new and never caused a problem!

I will post in the wanted section but if anyone has a timebase system switch for one of these (long shot I know) I would be most grateful if you could get in touch. I really would like this set to be fully switchable after all of this work. The timebase switch has been removed and soldered up. Quite a good job has been done but it would be nice to be able to have it working on both systems.

The smoke stack seems in good fettle. Hope it stays that way!

More soon... hopefully.

toshiba tony 9th Jun 2019 12:44 pm

Re: Alba TC1525 G6 Dual Standard.
 
I had a soft spot for the G6 s\s. After what I read on here the d\s faired better. I never had one, and as has been said the d\s was better. The thought of owning one scared me. But sparkling pictures I believe. Now the K70\80, I loved them.

MickMcmichael 9th Jun 2019 8:27 pm

Re: Alba TC1525 G6 Dual Standard.
 
Some progress to report. Odd issues still abound!

Replacement IF gone in. Leads resoldered into position. Check once, check twice, check again and switch on ... hold it, wait a minute, something doesn't look right. Switch off.

Someone in the past had replaced a wirewound resistor in the power supply on the tagstrip at the bottom of the chassis. They had soldered two resistors in series to make up 220 ohms.

In the process of moving all the leads about to replace the IF, I had moved these two series resistors to one side and noticed that there was a gap, a space on the tagstrip that's not shown in the component layout.

The component layout says that there should be R1072 in this vacant space. It feeds 12v to the tuner and is 15k in value. It was gone - not there - disappeared!

Switch on again and watch the replacement IF for smoke. None to be seen. Venture into set with meter probe to the tuner. No 12v !

Fit hefty 15k to the vacant position (it basically turns 220v into 12v with a bit of heat dissipation!). Switch on again, apply RF signal from freeview box and wait.

Buzz buzz. Tune button 1 on tuner and get full sound but still blank raster; a bit pink. I thought I could see some movement in the raster so I turned up the brightness. The relay clicked on the tube base. The 12v supply which I'd just restored went down to 8v and sound disappeared. Turned brightness down again, relay clicked and sound came back. 12v restored. Uh?

How odd!

But it's definitely progress. There's apparently two 12v supplies to the tuner so I need to check both. But if someone had actually removed a 15k resistor from the power supply, what else is missing?

Time will tell. All good fun.

slidertogrid 9th Jun 2019 10:13 pm

Re: Alba TC1525 G6 Dual Standard.
 
Hi Mick
It sounds like someone has been a bit busy previously with this set! It reminds me of the sort of sets bought ex rental "untested off the pile" back in the late 70's from the likes of Carters in Ilkeston. What they really meant was "everybody has had a go and given up" ;D
I am sure you will sort it... Give me a shout if you need a hand... I'll make the tea and do the swearing for you!
:thumbsup:
Rich.


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