I saw this on eBay, the listing stated "totally dead when power applied". The photo of the fascia was not that clear, but I thought I recognised it from one of my brochures, and I could just about make out a very rubbed out print stating "T xt cle". No remote, as usual missing!
Now, as part of my Teletext drive, I've been after a period portable teletext TV for that side of the collection, and this would be perfect. Anyway, I made a cheeky offer thinking that will be rejected, went to bed and thought no more of it. The next day I found I had bought it, and it was at the mercy of Parcel Force to deliver.
I fully expected it to arrive in pieces, it arrived today and much to my delight the vendor had packed it really well in a cocoon of bubble wrap, inside a massive box, not one that could be thrown about, a cunning plan Baldrick! Having said that, I think parcel force had done their damnedest to uphold their reputation for mishandling parcels, as when I lifted the TV out of the box I heard the familiar sound of tumbling bits inside. I need not have worried, this turned out to be two fixing posts for the rear cover, the bottom two. Thankfully, these easily glued back on. A safety pin and a .1uF 250V orange drop cap also dropped out, hmmm not another safety pin fuse bodge? Of course, now we know why when power was applied it was dead, the safety pin was missing from the fuse. 🤣
Unlike the Philips K35 I picked up at the weekend which is pristine inside and out, this is the total opposite. The insides looks high hour, I'm not too bothered because if the CRT is good, I plan to install that new old stock KT3 chassis, but as I say that is wholly dependent on the CRT at least having some reasonable life left in it. It will be tested in due course.
Fortunately, I had the exact remote for this TV in stock, unfortunately, inside it had been abused, someone had broken the flexible ribbon that contains the tracks to the keypad. This has rendered it virtually useless, so I'm on the lookout for a replacement or at least the internal keypad with flex ribbon.
I couldn't recreate the original facia print, which was in a mild green stating "Teletext Ceefax Oracle", I just added teletext with my label printer. For now, some pics. Overall, I'm really pleased to have one of these cute little teletext sets for the collection.
p.s.
Another TV is arriving this afternoon via Shiply so expect another thread.
You don't necessarily need a separate remote for each teletext TV. If you can find an RC5991, that was a 'universal replacement' and worked most Philips teletext TV's (not G11 though). It also had a print button for the K35 printer set.
You don't necessarily need a separate remote for each teletext TV
Hi Rich that may be so, but the original, like most remotes of the period, to me, are a thing of beauty, and form all part of the experience of using the TV. Opposed to the "modern" look and feel of the RC5991 and others.
I do have a universal TopTel remote, kindly given to me by @jayceebee , that literally has hundreds of period TV codes. It has been programmed on more than one occasion to cover for a missing remote. The K35 is in there as is the PYE and many Thorn sets, but as I say I still prefer to have and use the original.
If you can find an RC5991, that was a 'universal replacement' and worked most Philips teletext TV's (not G11 though). It also had a print button for the K35 printer set.
Thanks to the pointer on the RC5991, having said all that above, I have just bought one as I'm sure it will prove very useful. Though, as I say, there's just something magical about using the original. Like everything modern, cars as a good example, they have forgotten how to be individualistic in their designs. Perfect example (see below) here, eight from the past, instantly recognisable, then the modern monstrosity to the far right that could be any manufacturer. So given the choice of using a universal over an original, only if I really have to!
Why anyone would choose to go into design these days is beyond me, it seems whatever they're teaching has sucked out any creativity. Ignore me, just an old Boomer going on about yesterday, but am I so wrong?
Philips actually supplied the RC5991 as a replacement for nearly all RC5 remotes irrespective of which one was ordered (a service replacement). Back in 'the day' most remotes had a fairly short life for one reason or another, the common one being coffee tea or beer being spilt into it or the dog chewing it (yes)! It was probably cheaper in the long run to have one standard remote rather than keeping special production lines up for individuals.
On later (1990's) sets the RC5991 also enabled those TV's to be put into Service Mode.
One thing I have discovered about this particular version of the KT3 is, it has a big transformer, now that explains the weight of the TV, T001 and all the associated components. Now, I have a fair amount of data pertaining to the KT3, but nothing on this module and no mention on the cct diagrams, unless I'm being a twonk, which is possible. I have established it is an early version KT3, not second edition.
Anyone come across this version before and do you have data for this module or know its function?
OK, it was twonk-itus.... It's the Teletext power supply. You will have to forgive me, I've not come across this before so it threw me. I found it a 20" service manual.
Most KT3s in Oz were isolated. The mains transformer was a C-core, it sat in between the two chassis brackets, was screwed to the cabinet and plugged directly into the P/S module on the lower RHS of the monopanel. It had neat clip-on plastic covers to protect against contact with the nasties.
With constant competitive cost pressures, the transformer eventually disappeared, both on the KT3s and the 63cm - only KL9s. For a while, Pye Marrickville supplied us with transformers to re-fit when we were doing the AV IO conversions. We also fitted 3 core mains leads and grounded the chassis metalwork.
I don't now have any documentation of these sets but I know someone who does. If there is interest I could ask him to scan them.
This was in the "canning factory" era. Pye's version of the KT3 was called a T38. It had a re-written service manual which was considerably more useful than the Philips one.
One thing I have discovered about this particular version of the KT3 is, it has a big transformer, now that explains the weight of the TV, T001 and all the associated components. Now, I have a fair amount of data pertaining to the KT3, but nothing on this module and no mention on the cct diagrams, unless I'm being a twonk, which is possible. I have established it is an early version KT3, not second edition.
Anyone come across this version before and do you have data for this module or know its function?
Unless my memory is failing...I think ALL KT3 with teletext were Edition 2. You can tell by looking at the chroma module. It will have a single chroma chip (think it was a TDA3560) and a smaller switching chip (to switch the RGB outputs from Teletext to TV). Its also taller than the Edition 1. The Edition 1 had a smaller chroma panel with two small chips just for chroma decoding....no switching chip required on those. Incidentally, editions 1 and 2 chroma panels are not interchangeable.
'edit' Just looked back over the pictures and it's an Edition 2....taller chroma panel.
Hmmm well it IS confusing! I never saw an Edition 1 teletext. Anyway yours is Edition 2. It would be interesting to see if there are any Edition 1 text sets around. Later non-text Edition 2 sets also had the smaller chroma PCB but only one chip.
Thanks for the clarity, Rich, much appreciated. I was really flummoxed this morning, as I just couldn't fathom or find anything about the extra TX and module. I was looking in all the portable KT3 service manuals, it was only when I looked in the 20" KT3 manual I found it listed there. Furthermore, I'd not come across a set that needed a dedicated power supply for teletext. It was then suggested to me that the KT3 was not originally designed with teletext in mind and the chassis, as is, was likely not capable of providing enough power.
As mentioned in post #1 I will be installing an unused 'New old stock', KT3 chassis I bought a while back.
I still have the Philips V6600 isolated-chassis monitor incarnation of the KT3 chassis- it has a chunky C-core (very Philips!) transformer in the same place between the plastic motherboard supports. It simply provides 1:1 isolation into the existing works. I used it for many years (about 20?) with its partner V6100 tuner/text decoder/remote interface box- this latter even had sufficient room (underneath the text decoder's compartment) for the similar-sized Toshiba Nicam decoder evaluation board that was apparently made available to manufacturers in the run-up to over-air Nicam transmissions. Someone at work had a contact who got hold of about a dozen of these boards (nice GRP single-sided construction), I spliced mine into the existiing Zweiton decoder board with its blue ceramic Philips hybrids, most of which was of course redundant in the UK. The existing PSU seemed to cope happily with the additional +5 and +12 requirements of the Nicam decoder. The V6100 became a doorstop with the cessation of analogue transmission, but I've hung onto the V6600 monitor. This was trouble-free, apart from an early failure of the apparently unreliable white case long-sided and square box profile tripler, replaced with a standard universal type.
OK my uneducated plan to use the brand new KT3 chassis in the Teletext 16" teletext PYE 42KT3157/05W, looks to be a non-starter, unless I can fathom out compatibility.
Also, the PYE teletext has a different supply board, than the one in the brand new KT3 chassis. It has more in common with the K30 supply board, but even that mildly differs to the K30 supply board with regard to the configuration of D303, R303, C306 & S301. Then the decoder in the teletext is completely different to the on in the NOS KT3 chassis.
Supply differences
Decoder differences
This kt3 chassis appears more like a k30, confused I am
Front volume +/- does not function, not the channel. User controls behind the panel, master vol, brightness and colour do.
Tuned into signal, audio heard, but unable to get picture lock.
This isn't a standard fit
Nor this
Both in the line cct TDA2571 (SMPS control) ref freq input on pin3 to (TDA2581 (lin field/osc) pin 8 horizontal sync.
Me thinks someone has been a bodging but why, and what on earth do I use as a reference cct? As @jayceebee would say, "Looks like another one has hit your bench!".
that capacitor you found in the bottom of the set wouldn’t happen to be the right value for the one with the bodged resistor across it would it ?
Looking at the new kt3 chassis I have, yes it is the exact value and type. However, when I went to have a look on the print-side I find the bodgery has resulted in an open trace, to R457 effectively cutting off the hoz sync.
Reverting it back to standard by removing the parallel 100R across c459 and removing that mullard tropical on the rear, has resulted in a much dimmer but still unlocked picture. Putting it all back gives much brighter raster, but still unlocked. This is so weird!
This, I believe, is what they've done, (see below) why is beyond me!
As I mentioned above, reverting it back to KT3 std by removing the tropical cap and parallel resistor, only results in the same scenario but with less bright raster. This is a sheer brain killer. To top it all got a massive belt of 300V off the end panel when I tried to remove it, thumb touched one end of fuse holder other finger on one side of R294..... most unpleasant. Now I croc clip in a 100R from R294 to chassis every time I power off.
So what are they doing here and why?
p.s.
I've paralleled the 100R on the back instead of on the chassis side, easy to see their mod/bodge or whatever it is.
p.p.s
@unit-no-16 I believe you have this exact same TV with teletext, what does yours have in this position. I'd wager not this extra cap and resistor bodge, and it's a failed attempt at fixing another underlying fault.
I remember a fault on the text power supply panel in the bottom of the set causing sync problems, if the 5 volt supply failed it caused loss of sync. check for dry joints cracked panel due to the weight of the transformer and the regulator. I don't know if the modge you have would affect the sync? maybe it was to alter the effect of the horizontal shift adjustment. Strange that if has an effect on brightness... Is the electrolytic near the focus pot OK? They would go open and affect the brightness and cause greyscale drift.
