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-   -   Ferguson TX100 composite video? (https://www.vintage-radio.net/forum/showthread.php?t=155851)

GadgetM 19th Apr 2019 11:23 pm

Ferguson TX100 composite video?
 
Hi everyone, I have a Ferguson tv from the 80's that uses the tx100 chassis, it has only got rf in.
Just wondering if anyone here knows of a way to insert composite video and audio straight in to it.
RGB input would be ideal but I believe this might require some serious modifications, so I'd settle for.composite.
The reason being that I think the IF section needs re-aligning and I don't have the relevant signal generators and scopes to do it properly.

Any help would be gratefully received.
Cheers

dazzlevision 20th Apr 2019 7:40 am

Re: Ferguson TX100 composite video?
 
2 Attachment(s)
Ferguson did market “Peritelevision” (another name for SCART) kits for at least some TX100 chassis sets, so feeding in external RGB, composite video and audio is possible. The kit in the photos does also include RGB input capability.

GadgetM 21st Apr 2019 1:33 pm

Re: Ferguson TX100 composite video?
 
Aha so it can be done! thanks for that info, the big question is where to find one of those kits?

Nuvistor 21st Apr 2019 1:39 pm

Re: Ferguson TX100 composite video?
 
I don’t know about the TX100 but some chassis designs from that period had the chassis at half mains potential.
Something to check and if necessary to be aware of.

dazzlevision 21st Apr 2019 1:43 pm

Re: Ferguson TX100 composite video?
 
The TX100 chassis is mains isolated, apart from the “hot” side of the switch mode power supply circuitry.

dazzlevision 21st Apr 2019 1:45 pm

Re: Ferguson TX100 composite video?
 
Quote:

Originally Posted by GadgetM (Post 1138643)
Aha so it can be done! thanks for that info, the big question is where to find one of those kits?

Ebay possibly, NVCF/BVWS events, or you might be able to make one up, using the circuit diagram in the full TX100 service manual.

Nuvistor 21st Apr 2019 2:05 pm

Re: Ferguson TX100 composite video?
 
Thanks for the info.

GadgetM 21st Apr 2019 6:31 pm

Re: Ferguson TX100 composite video?
 
Thanks for the info, I'll keep an eye out on eBay. In the mean time I'll try and find a full service manual, mine has bits missing.
Cheers :)

GadgetM 21st Apr 2019 7:02 pm

Re: Ferguson TX100 composite video?
 
I don't suppose anyone out there has a circuit diagram for that add-on board?, it's not in the tx service manuals I found.

cheerfulcharlie 21st Apr 2019 7:42 pm

Re: Ferguson TX100 composite video?
 
howa bout a modulator, something like this?.

https://www.ebay.co.uk/itm/USED-Labg...gAAOSwLjxaafuU

That one is not complete as they are mostly second hand as there is not much call for them these days.
Looks like you will need a 9v power supply and a screw in RF plug for the back on that one..
...but probably you might find a complete a one on further Ebay browsing? It's important to look for an AV to RF converter and not a RF to AV converter as there lots more of them around in comparison.

GadgetM 22nd Apr 2019 9:23 pm

Re: Ferguson TX100 composite video?
 
Thanks cheerfulcharlie, but I already have an rf modulated freeview box, my reason for wanting to insert composite video was to bypass the 'out-of-alignment'- tuner/IF section.
The picture has a lot of colour subcarrier noise and I just can't seem to dial it out with the appropriate filter coil so I thought "sod it... I'll see if I can bypass it altogether and inject composite video instead"

Studio263 24th Apr 2019 7:55 am

Re: Ferguson TX100 composite video?
 
The TX100 uses a surface wave acoustic filter in its IF stages so no re-alignment is necessary (or possible!) there, it either works properly or it doesn't. These are very reliable components; I don't ever recall seeing a faulty one.

There are normally only two coils to trim, one to balance the AFC discriminator and one for the intercarrier sound, neither really need anything more than a good signal to adjust.

What is the actual fault? Sorting this out is probably much easier than trying to lash things up to work around it.

ChrisKt 24th Apr 2019 2:06 pm

Re: Ferguson TX100 composite video?
 
I have the complete Thorn service manual for the TX100 with the schematic of the SCART interface board (Part PC1594). It is quite complex with all the additional switching but would at least show you where to patch in.

Just registered so I probably cannot post a scan - probably easier to send you the full manual. I have no use for it (it has escaped several clean outs:)) as the set was disposed of long ago.

HTH

Chris K

GadgetM 24th Apr 2019 10:20 pm

Re: Ferguson TX100 composite video?
 
Quote:

Originally Posted by Studio263 (Post 1139352)
The TX100 uses a surface wave acoustic filter in its IF stages so no re-alignment is necessary (or possible!) there, it either works properly or it doesn't. These are very reliable components; I don't ever recall seeing a faulty one.

There are normally only two coils to trim, one to balance the AFC discriminator and one for the intercarrier sound, neither really need anything more than a good signal to adjust.

What is the actual fault? Sorting this out is probably much easier than trying to lash things up to work around it.


The problem is with strong colours, they're grainy as hell with colour noise, coloured text or subtitles looks pretty bad. Colour bars show it up well, the noise/dot crawl between each colour bar.
There is the 4.43MHz chroma trap (L6) which I have adjusted for minimum patterning, but minimum is still not good.

GadgetM 24th Apr 2019 10:23 pm

Re: Ferguson TX100 composite video?
 
Quote:

Originally Posted by ChrisKt (Post 1139448)
I have the complete Thorn service manual for the TX100 with the schematic of the SCART interface board (Part PC1594). It is quite complex with all the additional switching but would at least show you where to patch in.

Just registered so I probably cannot post a scan - probably easier to send you the full manual. I have no use for it (it has escaped several clean outs:)) as the set was disposed of long ago.

HTH

Chris K

Thanks Chris K! that would be very useful, perhaps send a private message to arrange that, happy to reimburse you.

ChrisKt 25th Apr 2019 1:48 pm

Re: Ferguson TX100 composite video?
 
Will do once I've worked out how to PM. The manual is very detailed with lots of explanatory notes and diagnostics so it may help with repairing the RF/IF section. I suspect helpful manuals like this don't exist any more. Don't worry about the postage.

If anyone is interested, I also have the manual for the 9000 series chassis.

Chris K

Studio263 25th Apr 2019 3:05 pm

Re: Ferguson TX100 composite video?
 
Quote:

Originally Posted by GadgetM (Post 1139572)
The problem is with strong colours, they're grainy as hell with colour noise, coloured text or subtitles looks pretty bad. Colour bars show it up well, the noise/dot crawl between each colour bar.
There is the 4.43MHz chroma trap (L6) which I have adjusted for minimum patterning, but minimum is still not good.

In that case a video input will not help you, the fault is probably in the decoder. Try feeding in a monochrome signal (switch your DVD player / freeview box to S-Video), if the results are clean that confirms it.

I'd change the chroma IC first (the big 28 pin one, TDA3562?), you never know your luck. Check also the components around the chroma trap, especially if the tuning isn't very 'sharp'.

AC/HL 25th Apr 2019 3:12 pm

Re: Ferguson TX100 composite video?
 
Chris,
Click on Gadget's username to send a PM.


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