I have this Ferguson Television, a hybrid and i think it´s from the early 1970ies, it have 5 tubes, some transistors and a IC circuit, very similar to the X680 chassis from Philips around same time (1970-1972), this is afterall in okay condition, i have never have power on it until now.
The serial resistor to the heater was o/c, but the value on the resistor was stamped on the resistor "117" ohm, so the solution was 2 x 220ohm 7 watt effect resistors in parallel, and that bring the tubes to life again,the olny fault i think it have is the vertical deflection tube is off.
The question to you is, is this set specific made for the European market, the design looks very Western European like,
Alex 😉
That's a Thorn 1500 chassis
If and when you need the service data I can scan the manufacturers service manual for you. However you will find already in the library the LLJ article on the 1500 which is probably all you will need.
You're probably not aware of * LLJ ( Les Lawry-Johns), he was our ultimate TV repair hero and in the UK his articles ( from the magazine Television) are the stuff of legends. Sadly now departed but his work lives on to inspire further generations of TV repairers.
* The man himself
Chris said
That's a Thorn 1500 chassis
Thanks Chris 😀
I am guessing the vertical output valve is a PCL85/805, if you have a valve you can try it, if not voltage checks on the valve will be useful.
I usually found that valve to give poor vertical linearity or lack of height rather than a frame collapse but the age it is anything is possible.
That's a 1500 chassis alright!
Chris: If you haven't already scanned the 1500 manufacturers manual yet, I recently scanned all mine for someone, and you are welcome to it for the library! I can email it to you if you wish?
Regards,
Lloyd
nuvistor said
I am guessing the vertical output valve is a PCL85/805, if you have a valve you can try it, if not voltage checks on the valve will be useful.I usually found that valve to give poor vertical linearity or lack of height rather than a frame collapse but the age it is anything is possible.
Could be a dry joint, possibly valve base or frame output transformer.
Lloyd said
Chris: If you haven't already scanned the 1500 manufacturers manual yet, I recently scanned all mine for someone, and you are welcome to it for the library! I can email it to you if you wish?
Regards,
Lloyd
Hi Lloyd,
I haven't so that would be great. You can try the members upload service here if you like
Chris said
You can try the members upload service here if you like
Ok, done! There should be 5 files in total, 2 service manuals, a bit about the varicap tuner, a service manual supplement, and a bit about installation adjustments. Hope it all comes through ok!
Regards,
Lloyd
Lloyd said
Ok, done!
Regards,Lloyd
Yes the service e-mailed me stating files were ready. They've now been moved into the library. Good to know the service is working as it should. Thanks Lloyd, much appreciated.
There you go Alex, all the 1500 data you could possibly need.
Fascinating! Does indeed look like an export Thorn 1500 chassis model. You mentioned an IC however. The UK 1500 is valve and transistor only so perhaps they could be some circuit changes?
Very impressive cabinet and station selector bank too. Always look impressive!
All sorts of causes of frame (field) collapse on these sets. The connections to the frame output transformer could have become fractured on the PCB or a wire off the scan coils as two examples.
Sure you'll have it working in no time.
Cheers
Brian
Wow! thats a very rare version of the 1500 series chassis that we know and love in the UK, I have an idea it may be a close relative of the 1540 chassis probably with a TX number somewhere stamped near the LOPT. The differences, a proper IF strip rather than wideband printed coils, spot the IC near the video output transistor and the coil near the PY800 suggests that the line oscillator valve might be a PCF802?
The 1540 chassis that was released in the UK as a schools receiver for group viewing, it was also fitted with a transformer so it was fully isolated for connection of VCRs etc .A very interesting set and it also seems to have the same NSF tuner as fitted to your Rank Arena.
For your field collapse the 1500 circuit will be very similar in this area but I doubt the component reference numbers will match. There are probably two 18K resistor across the field transformer primary, check these after replacing the PCL805.
John.
I missed that IC earlier!
I wonder if this set has a thermistor hidden on the scan coils, Thorn liked those, but I don't know if they used one on the 1500, or whatever this one actually is. Might be worth a look to see if it has one and if it's gone OC.
regards,
Lloyd
The scan coils don't appear to be the normal Thorn type fitted, it may still have a thermistor though when it goes completely o/c the clue is that the collapse usually has noticeable kinks in it.
John.
Well I'm certainly very impressed with your collection for one! What model is the set in your avatar?
Any luck with the Ferguson 3547 ? I forgot to mention a dud spot on the height control can result in frame (field) collapse. Is there a "tickle" sound from the frame output transformer?
cheers
Brian
Focusdiode said
Well I'm certainly very impressed with your collection for one! What model is the set in your avatar?Any luck with the Ferguson 3547 ? I forgot to mention a dud spot on the height control can result in frame (field) collapse. Is there a "tickle" sound from the frame output transformer?
cheers
Brian
Focusdiode said
Well I'm certainly very impressed with your collection for one! What model is the set in your avatar?Any luck with the Ferguson 3547 ? I forgot to mention a dud spot on the height control can result in frame (field) collapse. Is there a "tickle" sound from the frame output transformer?
cheers
Brian
Thanx Brian.
Most of my little collections is TV´s made in Denmark, i really like the national brands, about the ferguson i noticed there is a small sound from the output frame transformer, it will be another project forward some day when i have the time for a new project.
The Tv in my avatar is this one Ducon TV600 it´s from 1960 and made at a little small factory in the middle of copenhagen, actually the factory have rooms in a huge apartment, tha factory only made B/W televisions and radios, they didnt begin on colour, it was to expensive to begin on that era, the factory closed for finally in 1970. 🙂
Alex 😉
I've just been looking through your flickr photos and see that this chassis is designated as a TX250 series. The video processing is done by a TBA550Q IC so this set with it's normal IF strip and providing the CRT is OK, should be capable of pretty good pictures (I hope).
A question for you Alex, can you tell me what type of valve (tube) is fitted V1 position. I can just see that the first letter is P, Is it a PCF802?
John.
I am a lucky guy, a friend of me have picked one almost similar up, it is 24", but same 1500 chassis, i notice that it only have 4 tubes (eks picture tube) do we have a schematic somewhere? how about the age? is it around mid 70ies? 🙂
Alex
do we have a schematic somewhere?
Alex,
I checked and you do have access to the data library and it contains an entire section full of Thorn 1500 chassis service data so have a look in there and you'll find what you need. For those those that don't yet have access but wish to follow along, there is thorn 1500 data available in the service departments "free-to-view" section called "servicing the black & white sets"?