B&W TV GEC Deluxe Nineteen Dual Standard

Hi Jan, I've spoken to our community GEC guru  @the_teleman he reliably informs me it is the BT449DST. I have the service manual for it, I will scan and upload first thing tomorrow morning. It will be in the temp data library for you to download.

@crustytv 

Superb! Thank you very much, Chris. Much appreciated! 

I couldn’t find anything about this set anywhere.

Dual standard black and white sets aren’t usually my cup of tea. But, I couldn’t justify just chucking it in the tip. It looks like quite an unusual one. Plus, I like a challenge 🤣

Managed to get ‘first light’ on it by snipping out a few leaky hunts caps and tacking some replacements on.

Hooked up a speaker and Powered it up through a lamp limiter for a bit, then gave it full mains. It come up with frame collapse. Swapped the 30PL13 that had gone to air and now I have most of a raster. Still a bit cramped up at the bottom and expanded at the top. 

Now there’s just no signals getting through. Not a peep of sound, slight crackle when you wiggle the audio output valve. Nothing on VHF either, not even a flicker on screen with changing the channels. 

I’ll update the thread when I download the service data and dive into the IF strip. 

Cheers. 
Jan

Just out of curiousity, will a PCL82 replace a 30PL13? Pinout is the same.

I'm interested in strange bottles we never saw in Oz!

Service manual for the BT449DST is now in the temp library, please let me know when you have downloaded, so I can remove.

Posted by: @yampy187

↑

I couldn’t find anything about this set anywhere.

That's the cool thing about VRAT, we might be a small community, but there is a lot of knowledgeable members here, one could say "small but perfectly formed" applies. 😉 😆 

@irob2345 There are differences in the specifications of the two valves, slightly more anode current and higher gm in the 30PL13. I seem to remember the PCL82 was used as a replacement in an emergency but was not recommended, usually had a  shorter life.

As for strange valves, Brimar used the USA type numbering system but I didn’t really see that many, mainly Mullard and Mazda. I think KB used Brimar valves, they were very good quality valves but it seems Brimar had good customers in manufacturing and military. Perhaps they were happy with those instead of chasing diminishing margins in domestic equipment.

What I like about the European numbering system, PCL82 for example is that the number gives a lot of detail about the valve whereas other numbering  systems are more opaque. The PCL immediately show a 300ma series heater with a voltage amplifier triode and a power output pentode. A usable equivalent is say a 16A8 which apart from heater voltage says little else, has it was probably intended for series heaters the voltage is less relevant.

Those are my thought but some would say ramblings.

Frank you are absolutely right about the numbering systems and Brimar. STC in Oz used Brimar in their products.

a PCL82 is the same as a 16A8, the ECL82 with which we are more familiar is a 6BM8. Yes, not much info apart from heater voltage and the number of accessible elements in the valve.

We had 2 valve manufacturers, AWV and Philips. It was possible to buy AWV-made valves rebranded Miniwatt or Mullard and vice versa, mainly dependent on if the type was US or Euro origin. AWV broke out of that cozy arrangement and started making their own versions of Philips types at the same time AWA released their P1 portable. And of course Mullard valves were made by Philips. I'm pretty sure AWV never made Decal types (e.g. EFL200 / 6Y9). They did make some high power transmitter valves though.

AWV and Philips both made diodes, transistors and ICs here.

Posted by: @nuvistor

↑

As for strange valves, Brimar used the USA type numbering system but I didn’t really see that many, mainly Mullard and Mazda. I think KB used Brimar valves, they were very good quality valves but it seems Brimar had good customers in manufacturing and military.

KB definitely used Brimar valves and the American nomenclature was due to the parent company being American, viz. ITT. It's also why you see some sets in France bearing an uncanny resemblance to KB ones, such as the LMT 1840 - LMT were also owned by ITT. Also Schaub-Lorenz in Germany - which may explain why ITT/KB cassette recorders often had a prefix of SL- in their model numbers.

Brimar used to make flat-faced CRTs for television camera viewfinders and indeed the military too.

A quick update on this. 

I have downloaded the manual (Thanks again,Chris) and have been having a little poke around the IF with a multimeter. The voltages around V3 - Common IF amp seem pretty close. Still bugger all getting through! If I inject a video signal into L21, I get an image lacking in contrast and buzz from the speaker.

it seems (to me) quite a complicated set, Compared to the late 70s/80s stuff I usually play with! And wondering what to check next.

Excuse the rats nest of tacked on caps. Didn't want to commit to fitting anything permanently if it turned out to be totally scrap 🙂

Cheers.

Jan

@yampy187 Check voltages on the IF valves, I note that the common IF seems ok.

Have you a signal generator, if so meter on the output of the video detector diode OA70 and inject a vision IF signal starting at the last IF grid and work back towards the common IF amp.

Worth checking the OA70,they do fail and that the IF stages are not unstable due to faulty decoupling capacitors.

It is well worth saving, it has a good LOPT and tube which can be the major stumbling block with sets of this age. The chassis looks vaguely similar to the earlier 405 only models and as a dual standard version is uncommon, especially with the UHF tuner fitted rather than a "convertible" set. 

I suggest not removing the UHF tuner valves unless the tuner proves to be 'deaf' in which case you have no choice, as the valves are the first suspect. The valve holders are a bit fragile and can be temperamental if disturbed.

The next gen series 1000 and 2000 chassis was much more common and a fair few appear even today. This is only the second one of this example I have seen. IMHO quite a find! 😎 

Rich.

@nuvistor 

Unfortunately, I don't have a suitable signal generator. The voltages on the IF valves seem pretty close to spec. Cant seem to find any shorted caps either. The OA70 seems to test OK. Possibly a faulty tuner? 

Cheers. 

Jan

@yampy187 Yes could be a faulty tuner but many other things as well. Have you a spare tuner to try?

Its a bit like working in the dark without some test equipment.

Do you have an ordinary radio-type signal generator that covers the IF frequency? With 500Hz or 1kHz modulation? That will do.

Thanks for the replies and suggestions guys. 

I don't have anything suitable to use as a signal generator. Only a basic function generator that does Square and Sine wave.

I think I'm going to pass this set on to someone else to play with. 

Thank you all for the help.

Cheers. 

Jan

Even a function generator in the square wave setting should be useful to signal trace the IF.

Posted by: @yampy187

↑

I think I'm going to pass this set on to someone else to play with. 

GUESS WHO?! 

Thanks, Jan! 

😁 No problem Wayne. 

Glad it got there in one piece! 

@wayned Hi Wayne in response to your request for help on the back cover. I'm sorry but I don't have the set I saw, it belonged to my mate Mick who moved it on some time ago.  I do have a 17" 405 "bow front" GEC in my collection so I can provide a photo of what is on that it would at least give you an idea of the design.

Rich

@slidertogrid that would be great Rich, cheers! I can kinda see where the vents were and what shape they were as there's some sun/weathering above the aerial connectors and obviously where the horizontal controls etc are supposed to poke out, but that's about it.