UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Television and Video

Notices

Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc.

Closed Thread
 
Thread Tools
Old 28th Jul 2022, 7:30 pm   #1
19Seventy7
Octode
 
19Seventy7's Avatar
 
Join Date: Jun 2018
Location: Essex, UK.
Posts: 1,306
Default Ferguson 3850 - Thorn 1615 "restoration"

Evenin' all!

Thought I'd do a write up of the set Zelandeth very kindly delivered to me yesterday afternoon as promised(Thank you again!) while running the set on another soak test, so here goes!

After a nice chat with Zelandeth about all things old I scurried the set in through the front door and straight into my room, all whilst praying I wouldn't be seen as I'm under very strict order "not to get anymore old stuff"

As if!

Mission accomplished! I ended up having a quick nose around inside the set before doing any real work and straight away I noticed that the set was getting ready to show us it's party tricks! It had several cracked joints around the coils, so I made a mental note of where and packed the set up again, disguised it in with my other sets and went out to see family.

I couldn't wait for today to work on the set so after getting home again at gone 9PM I dug the set back out and took it to the kitchen and reflowed any joint that I didn't like the look of, and the coils, and doubled up on the traces with some wire. I then noticed the CRT spring had snapped, so I did a rather basic repair to that which seems to have worked well, intertwining the two ends of the broken springs together and allowing them to grip one another, and then reinforced to make sure they didn't break loose again.

I then turned the set round, and showed the set some mains. The EHT rustled up with a nice, healthy sounding line whistle, and there was a decent amount of sound and I waited for a raster to appear

and waited

and waited

Finally a very dim and very out of focus and slightly cramped snowy raster made its appearance!

I connected a signal to the set and instantly a very blurry Test Card F popped up on screen, only fine tuning needed!

I instantly set to work adjusting the set, increasing the height and adjusting the focus and then adjusting the tilt of the picture and relocating it slightly, which took a surprisingly long time for some reason, I still can't get the focus just right but that's no fault of the set (I don't think!) I just cannot get a decent grip on the control with any tool I use.

I then gave it a soak test where it ran very well for about 30 minutes with the picture constantly improving until there was a fizzle and a spark and smoke and a smell.. That unmistakeable smell of a RIFA objecting to life. That was duly taken out and a 1000V film cap replacement put in place for now until I can find a better replacement.

Its been playing away for the past hour or so now quite happily and touch wood it's been flawless except for the focus, which I will definitely sort out, and the linearity at the top of the screen, which is quite amusing watching peoples hairlines recede the closer they get to the top!

All in all I'm really pleased with this little set and I'm glad I managed to save it, especially as just the night before I saw the offer post I was saying how I wanted one to a fellow enthusiast! I believe it's also one of the very last large screen monochrome sets built here as it's dated 1983 inside.

I'll add some more photos of the set when I improve the focus and linearity - which is most likely going to be tonight!

PS - Does anyone have any tips on cleaning out scratches on CRTs without affecting the good parts? It's got quite a few scratches which all seem to have dirt in them, which I think if cleaned out would make them far less noticeable.
Attached Thumbnails
Click image for larger version

Name:	1.jpg
Views:	229
Size:	70.1 KB
ID:	261744   Click image for larger version

Name:	2.jpg
Views:	203
Size:	85.1 KB
ID:	261745   Click image for larger version

Name:	3.jpg
Views:	221
Size:	70.3 KB
ID:	261746   Click image for larger version

Name:	1C.jpg
Views:	216
Size:	96.0 KB
ID:	261747  
19Seventy7 is offline  
Old 29th Jul 2022, 10:51 am   #2
Welsh Anorak
Dekatron
 
Welsh Anorak's Avatar
 
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,884
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Nice to see it working!
Now you REALLY do want another one, don't you?
__________________
Glyn
www.gdelectronics.wales
Welsh Anorak is offline  
Old 29th Jul 2022, 12:20 pm   #3
Hybrid tellies
Nonode
 
Hybrid tellies's Avatar
 
Join Date: Jan 2004
Location: 1966-1976 Coverack in Cornwall and Helston Cornwall. 1976-present Bristol/Bath area.
Posts: 2,965
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

That has come up well and looks very promising. I do remember the few I have seen giving good pictures.
__________________
Simon
BVWS member
Hybrid tellies is offline  
Old 29th Jul 2022, 12:26 pm   #4
Welsh Anorak
Dekatron
 
Welsh Anorak's Avatar
 
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,884
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Like the 1500 before it, these tubes did have quite a soft focus. Leaving it working will sharpen things up.
__________________
Glyn
www.gdelectronics.wales
Welsh Anorak is offline  
Old 29th Jul 2022, 6:57 pm   #5
19Seventy7
Octode
 
19Seventy7's Avatar
 
Join Date: Jun 2018
Location: Essex, UK.
Posts: 1,306
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Quote:
Originally Posted by Welsh Anorak View Post
Nice to see it working!
Now you REALLY do want another one, don't you?
It’s great, and it was refreshing to have an easy repair!

I would love to say yes to another but I don’t want to push my luck, and to be honest I really don’t know where this one is even going to go!

Quote:
That has come up well and looks very promising. I do remember the few I have seen giving good pictures.
Thank you, I’m really pleased with it, and it keeps getting better and better!

Quote:
Like the 1500 before it, these tubes did have quite a soft focus. Leaving it working will sharpen things up.
It’s definitely improved, as shown in the photos below of the before and after of the picture geometry and I’m sure it’ll improve some more. It looks pretty good on normal watching but text shows the softness of the picture, but overall I’m happy!
Attached Thumbnails
Click image for larger version

Name:	369C91C6-5D3B-46F3-86EF-A2511BEB58AC.jpg
Views:	127
Size:	76.7 KB
ID:	261790   Click image for larger version

Name:	F3475E1F-A5A9-4ADC-B6EA-57294DCE40ED.jpg
Views:	147
Size:	81.8 KB
ID:	261791  
19Seventy7 is offline  
Old 29th Jul 2022, 8:06 pm   #6
slidertogrid
Octode
 
slidertogrid's Avatar
 
Join Date: Apr 2005
Location: Peterborough, Cambridgeshire, UK.
Posts: 1,897
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Quote:
Originally Posted by 19Seventy7 View Post


PS - Does anyone have any tips on cleaning out scratches on CRTs without affecting the good parts? It's got quite a few scratches which all seem to have dirt in them, which I think if cleaned out would make them far less noticeable.
I used smokers tooth paste way back to get scratches out and those marks that were caused by the screen rubbing on another during transit . the level of success does depend of course on how severe they are. I saw some re-gun tubes that had been heavily polished so much that there was a slight 'dip' in the faceplate. The toothpaste was the dry powder type that you could add water to to make a paste. If you use anything more abrasive you can cloud the glass so go careful!
That tube if looking much better in the later pictures !
slidertogrid is offline  
Old 29th Jul 2022, 8:31 pm   #7
19Seventy7
Octode
 
19Seventy7's Avatar
 
Join Date: Jun 2018
Location: Essex, UK.
Posts: 1,306
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Ah that’s a good idea. I’ll definitely look into that. I presume that it’s done with a cloth?

The tube is definitely a good’un! I hoped it would be as the set looks fairly low hour elsewhere

Thanks
‘77
19Seventy7 is offline  
Old 29th Jul 2022, 9:23 pm   #8
slidertogrid
Octode
 
slidertogrid's Avatar
 
Join Date: Apr 2005
Location: Peterborough, Cambridgeshire, UK.
Posts: 1,897
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Yes just a soft cloth it does take time but it will improve scratches if not cure them I suppose with care you could try a cutting compound designed for paintwork on c**s it is available in various grades ... I have also used a paste cleaner sold to polish chrome on scratched (non CRT glass) with some success but proceed with caution!
slidertogrid is offline  
Old 29th Jul 2022, 11:08 pm   #9
19Seventy7
Octode
 
19Seventy7's Avatar
 
Join Date: Jun 2018
Location: Essex, UK.
Posts: 1,306
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

I’ll definitely give it a go, I don’t want to be too harsh with it as there’s no turning back! I could probably live with the scratches, they’re not that noticeable when watching the set anyway, it’s more for the general cosmetics when off

Thanks
‘77
19Seventy7 is offline  
Old 30th Jul 2022, 12:05 pm   #10
Richard_FM
Octode
 
Richard_FM's Avatar
 
Join Date: Sep 2017
Location: Stockport, Cheshire, UK.
Posts: 1,999
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Good to see you've managed to get it running without too much effort.

It amuses me that the later B&W sets are almost empty inside, as the main circuit board can be made small due to the solid state components.
__________________
Hello IT: Have you Tried Turning It Off & On Again?
Richard_FM is offline  
Old 30th Jul 2022, 12:06 pm   #11
Welsh Anorak
Dekatron
 
Welsh Anorak's Avatar
 
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,884
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

I'd be careful.
Back in the day we had a polishing kit which used jeweller's rouge and a cloth covered drum you put in an electric drill. It worked in that the scratches disappeared, but when you moved your head you could see the prismatic effect which rendered the set unsaleable.

The toothpaste mentioned is unlikely to scratch the glass so is worth a go.
__________________
Glyn
www.gdelectronics.wales
Welsh Anorak is offline  
Old 30th Jul 2022, 6:41 pm   #12
19Seventy7
Octode
 
19Seventy7's Avatar
 
Join Date: Jun 2018
Location: Essex, UK.
Posts: 1,306
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

I agree! And it makes accessing things so much easier too, I really love the hinged chassis Thorn used.

I am a little hesitant to polish the scratches out I’ll admit, as I don’t want to make the CRT any worse. I was looking more at cleaning the dirt out of the scratches rather than removing the scratches in general. I don’t find the scratches distracting at all, only just the discolouration, but I’ll look into it!

Thanks
‘77
19Seventy7 is offline  
Old 31st Jul 2022, 8:41 am   #13
Heatercathodeshort
Dekatron
 
Heatercathodeshort's Avatar
 
Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 9,145
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

To clean the scratches simply use a small nail brush and some warm kitchen/bathroom cleaner then rinse. The glass is very 'hard' and it is extremely difficult to remove scratch marks. J.
Heatercathodeshort is offline  
Old 31st Jul 2022, 5:39 pm   #14
Vintage Engr
Heptode
 
Join Date: Jan 2008
Location: Shrewsbury, Shropshire, UK.
Posts: 824
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

I agree with Glyn,
We used to use the same kit, & one had to be really careful otherwise you'll be grinding 'mini-lenses ' all over the screen.

Great picture though, looks good as new.

David.
Vintage Engr is offline  
Old 1st Aug 2022, 10:33 am   #15
Welsh Anorak
Dekatron
 
Welsh Anorak's Avatar
 
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,884
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Glad you like the Thorn hinged chassis. You would have thought the earlier hybrids would suffer from the valves drooping, but they rarely did. The main trouble with this arrangement was the frame transformer which went dry-jointed. Not a problem with yours.
And show me an engineer who worked on the 1400 chassis that didn't have a couple of burn marks from the line output valves' top caps! Lunkily Thorn put them on the hinged side for the 1500.
__________________
Glyn
www.gdelectronics.wales
Welsh Anorak is offline  
Old 1st Aug 2022, 1:42 pm   #16
19Seventy7
Octode
 
19Seventy7's Avatar
 
Join Date: Jun 2018
Location: Essex, UK.
Posts: 1,306
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Quote:
Originally Posted by Heatercathodeshort View Post
To clean the scratches simply use a small nail brush and some warm kitchen/bathroom cleaner then rinse. The glass is very 'hard' and it is extremely difficult to remove scratch marks. J.
Ah I'll try this route first, I did consider a nailbrush but didn't know if it'd be too abrasive. I probably sound overly cautious but I only want to make it better, not worse!

Quote:
Great picture though, looks good as new.
Thank you, I'm really pleased with it how far its come so far too

Quote:
Glad you like the Thorn hinged chassis. You would have thought the earlier hybrids would suffer from the valves drooping, but they rarely did. The main trouble with this arrangement was the frame transformer which went dry-jointed. Not a problem with yours.
It's definitely the easiest arrangement to work on that I've ever come across, closely followed by the Decca Bradford chassis. I'd love to work on a 1400 now, I've worked on a 1600 series chassis, a 1500 and now I'd like to find a 1400 - albeit not to burn my arms on!
19Seventy7 is offline  
Old 2nd Aug 2022, 12:59 am   #17
Zelandeth
Heptode
 
Zelandeth's Avatar
 
Join Date: Jun 2006
Location: Milton Keynes, Buckinghamshire, UK.
Posts: 931
Default Re: Ferguson 3850 - Thorn 1615 "restoration"

Really great to see this getting the attention it deserves, glad you've been enjoying working on it.
Zelandeth is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 3:45 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.