|
Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
|
Thread Tools |
24th Jul 2022, 6:37 pm | #1 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,224
|
AGA black and white TV
I have been asked to repair this TV which the owner imported from Sweden.
It was dead, having gone bang when the new owner plugged it in. The fault was the paper wax capacitors across the mains! Having replaced them I found a Rifa cap in the line 0/P stage that had cracked. When I replaced it I was rewarded with a raster with field problems. (See picture) The frame stage comprises of a PCF84 and a PCL85. I have replaced the cathode bias capacitor in the frame O/P stage, but time prevented me from going further. What might cause this fault? |
24th Jul 2022, 7:04 pm | #2 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,199
|
Re: AGA black and white TV
It could be a Swedish Philips chassis, I'm not sure which one or whether that's really the case, but you might be able to verify it by looking for labels and numbers on the chassis or the PCB (also in the copper pattern). That way it might be somewhat easier to find a schematic.
Last edited by Maarten; 24th Jul 2022 at 7:16 pm. |
24th Jul 2022, 8:27 pm | #3 |
Hexode
Join Date: Nov 2010
Location: Market Drayton, Shropshire, UK.
Posts: 485
|
Re: AGA black and white TV
Faults like this are often due to faulty components in the cathode of the PCL85, you say you have replaced the by pass cap but what about the cathode
resistor has it gone low normally about 270R? The set does have a Philips look about it. One Philips set had a frame output transformer that had a feed back winding that would go OC causing a fault like yours. Regards, Derrick. |
24th Jul 2022, 9:27 pm | #4 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,224
|
Re: AGA black and white TV
I checked the cathode resistor, it's a 390R but it went slightly high.
|
25th Jul 2022, 4:35 am | #5 |
Hexode
Join Date: May 2009
Location: Ryde, Isle of Wight, UK.
Posts: 419
|
Re: AGA black and white TV
Looks very much a Philips to me too, cramping at the bottom is normally
always associated with a fault in the Cathode circuit. what's the voltage on the cathode ? May be worth investigating Derrick`s suggestion, if the cap and resistor are OK. Ken, G6HZG.
__________________
Life is not Hollywood, life is Cricklewood. |
25th Jul 2022, 10:29 am | #6 |
Dekatron
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,921
|
Re: AGA black and white TV
What a strange looking TV! Is it AGA as in the stove manufacturers?
Could you hazard a guess as to the date - perhaps the CRT type will help. Hopefully the fault shouldn't take too long to track down - the CRT looks good. |
25th Jul 2022, 12:01 pm | #7 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,199
|
Re: AGA black and white TV
It would have been made around 1960-1965. It's the same AGA as the stove manufacturer. They actually made their electronics themselves and/or bought in from various manufacturers but at some point in time they seem to have switched to Philips made sets. I don't know whether Philips bought the rights to their name or they remained an indepedent trading company.
It would be relatively easy to confirm or reject the Phlips origin of the chassis. |
25th Jul 2022, 10:15 pm | #8 |
Nonode
Join Date: Sep 2017
Location: Stockport, Cheshire, UK.
Posts: 2,002
|
Re: AGA black and white TV
Interesting to see, I wasn't sure if there was a Swedish manufacturer who made their own chassis rather than just make sets around imported major components.
__________________
Hello IT: Have you Tried Turning It Off & On Again? |
26th Jul 2022, 9:28 pm | #9 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,199
|
Re: AGA black and white TV
Luxor certainly made their own chassis.
|
27th Jul 2022, 12:17 pm | #10 |
Hexode
Join Date: Jan 2011
Location: Düsseldorf, Germany.
Posts: 368
|
Re: AGA black and white TV
Hi,
I have the same set, and parted 1-2 of them out. In Sweden these models are called "tombstone" because of their style. Do you want the schematic? Regards, German Dalek
__________________
And now something completly different: MARC BOLAN, he was/is the real king of Pop Music! |
1st Aug 2022, 11:14 pm | #11 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,224
|
Re: AGA black and white TV
I’ve got the set back in the workshop and I’ve got the diagram. I’ll be away for a couple of weeks and will start on it when I get back.
|
14th Aug 2022, 10:20 am | #12 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,224
|
Re: AGA black and white TV
I've done more work on this set. I've replaced a number of RIFA type capacitors and I found a 1M resistor in the height circuit that had gone high. When I replaced it, I had full scan. Except I have flyback lines at the top of the screen.
i get quite a bright raster with lines, should I not get snow! The set at first seemed like it was VHF/UHF but there is no UHF tuner fitted. Did Swedish TV operate on 625 lines at VHF? There is no system switch and it's certainly not 405 line! As the set has a live chassis, I can't create a video input. What can I use as a converter? |
14th Aug 2022, 11:49 am | #13 |
Nonode
Join Date: Jun 2008
Location: Coningsby, Lincolnshire, UK.
Posts: 2,819
|
Re: AGA black and white TV
Have you got one of those multi standard modulators available? I have one and you can just feed in a signal from a freeview box or DVD player (anything that can output a 625 line signal really!) and then select what channel to output it on, and also set the sound frequency too. Have a look for ‘M69L RF Modulator AV-RF TV Converter UHF VHF Frequency PAL NTSC Standard’ in the usual places. I have successfully used one on an American Motorola 7” TV, in fact that’s what I bought it for, picture and sound were very good, and it didn’t mind having 625 lines fed to it!
Regards Lloyd |
14th Aug 2022, 1:13 pm | #14 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,224
|
Re: AGA black and white TV
Hi Lloyd,
Where did you get yours from? |
14th Aug 2022, 1:51 pm | #15 |
Nonode
Join Date: Jun 2008
Location: Coningsby, Lincolnshire, UK.
Posts: 2,819
|
Re: AGA black and white TV
Got mine off eBay a couple of years ago, they are available on Amazon and Aliexpress too. There is a version that accepts a hdmi input too!
Regards Lloyd |
14th Aug 2022, 6:23 pm | #16 | |
Hexode
Join Date: Oct 2012
Location: London, UK.
Posts: 498
|
Re: AGA black and white TV
Quote:
Sweden use 625 lines system B at VHF. Later UHF system G was used as well. Note also their mains was 220v so you will be overloading it on our 240v. |
|
14th Aug 2022, 11:16 pm | #17 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,224
|
Re: AGA black and white TV
There is snow, very faint snow, you can see it by turning the contrast up, the brightness down a bit and changing channels. It does have a 240V setting so I'll make sure its set for that.
|
28th Aug 2022, 9:12 pm | #18 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,224
|
Re: AGA black and white TV
We have a picture and sound! The height doesn't go high enough and there are flyback lines on the top of the picture. I will post diagrams soon.
|
28th Aug 2022, 9:43 pm | #19 |
Hexode
Join Date: Nov 2003
Location: Linkoping, Sweden
Posts: 493
|
Re: AGA black and white TV
|
28th Aug 2022, 10:26 pm | #20 |
Moderator
Join Date: Feb 2006
Location: Wembley, Middlesex
Posts: 7,224
|
Re: AGA black and white TV
Here is a scanned circuit of the line and frame timebases
|