It eventually made it to the bench! (TV22)

I think the TV22 bulb is much less scary and feels positively robust compared to the Mazda counter parts.

I have a murphy V230 with a CRM124, that gives me the right Heebie-jeebies. If you tap the bulb with the back of your nail on the MW22-16 it sounds thicker, same done to a CRM124 feels as thin as a wine glass.

Like you Jeffrey I'm not convinced its Pyrex, I'm sure I read Pyrex is a hard glass and the glass used in Mullard & Mazda tubes is a soft glass.

I was also under the impression that rather than being afraid of roundies ( with exception of the mazda bombs) its the rectangular ones that defy nature more.

I could have sworn I'd read plenty about it being made of Pyrex...

Anyway, it's still scary, it's quite light for the size of it so I can imagine it's fairly thin.

Once I get first light I will have to consider buying or making a standards converter, I'd rather make something as I don't plan to collect 405 stuff, I simply don't have the room

Dave.

I think the gun assy is pyrex.

I thought that Pyrex tubes were only fitted to pre-war TV's?
I agree about the Mazda CRT's being scarily thin, I have a CRM 121 which is awaiting refitting to a set.
I certainly won't attempt that after a few beers

I also thought pyrex was only used in pre war t.v,s.
I know from experience that RACS the tube regunners in france had great difficultly with pyrex crt,s but they rebuilt crm121,s and the mallard 9" mw22 series.

Davegsm82: You seem to be making some progress with restoring your TV22. You mentioned that you could hear the line whistle and the frame buzz, as well as obtaining a tiny spark from the EHT, but as yet, no "first light". You also mentioned that you don't have a standards converter yet.

Last year I started restoring a Bush TV22 (the Mk. 2 version, using EF80 valves in the RF deck) with similar results. After powering it up slowly on the variac, I could hear the line whistle and get a small spark from the EHT, but no picture on screen, even at 240 volts. The EY51 heater was lit, though.

I only got brightness on the screen after connecting the Aurora to the aerial socket. In my case, first light was a dim horizontal line, as the frame oscillator blocking transformer was faulty. With no signal connected, there wasn't even a line, just a blank screen.

I think if you connect a signal, you may be rewarded with some kind of picture. Maybe there's someone near you who has a standards converter. You could take your set there and try it.

As for capacitors, I ordered some of the "Suntan" ones from here : http://www.rapidonline.com/electronic-c ... itor-71096
They have quite long leads and they're cheap as chips! Some more cheap high voltage caps here (I used these to replace the heater decouplers) : http://www.rapidonline.com/electronic-c ... tors-74530

I went ahead and re-capped my set, even though I could not get any frame scan. Afterwards the horizontal line was a lot brighter. I used the line oscillator transformer from a Thorn 1500 chassis as a substitute for the failed frame blocking TX in the TV22. It worked reasonably well. I got a quite good picture but the frame linearity was slightly out, which may be due to the substitute transformer.

Yes the CRT does seem a bit scary. Mine has a small air bubble trapped in the glass. Does this make it more likely to implode?

Hamid_1,

I tried getting first light last night but as yet have had no luck, I refitted the tube and powered up all the way to full mains voltage.

Even with the lights out there was no sign of anything on the screen at all, no flicker, no line, no dull glow. Even with no signal I think there should still be some sort of output, the tube should be biased on a little bit (in theory, I've not checked the caps around the control grid of the tube).

I know there are a few people around me who have an Aurora, once I get a few more caps replaced and do some voltage checks then I'll maybe ask to borrow or bring my set to them.

One thing I noticed is that I was only able to achieve about 2.6kV on the EHT with my probe attached, perhaps this isn't enough to get those electrons firing their way to the phosphor.

My tube also has a little bubble in the glass of the faceplate, I've heard horror stories about them imploding but I figure that if it's lasted this long then it probably isn't going to just let go of its own accord, I doubt thermal stress from operation will cause an issue.

Anyway, feeling a little dejected I shoved the 22 back on the shelf in order to have a look at a little KB FB10, at least I managed to get 'first squeak' out of that, an odd little radio that one, the 6BW6 gets rather hot so i suspect the few paper 'orrible hunts on the underside are all duffers.

Dave.

Have you wiggled the ion trap magnet around?

Have you wiggled the ion trap magnet around?

No, unfortunately it was loose when I got the set, does it have a 'pre-set' position on the tube? unless I'm totally mistaken the one in my set looks like a tube clamp but just floats around on the neck, seems to have a very small magnet opposite the screw-clamp.

Can anyone advise how to set this up?

Thanks, Dave.

Run the set up and wiggle it around for maximum brightness and no corner shading. There's an arrow on some which should be pointing towards the face of the tube, otherwise it's a bit of a guess job. You stand a strong chance of getting nothing with it in the wrong place!

If you are worried that with your low EHT, you won't see a raster, make some interference with an electric bell mechanism, or relay wired to oscillate. You'll see that with the wiring in proximity.

Hi Dave, the LOPT sec is usually Ok on these, but it is the primaries that go faulty. After the set has run for a while and when switched off and discharged, see if the lower end of the LOPT tube is hot. This may be a sign of shorted turns on the pri.

Ed

Thanks Doz and Ed, I'll give those things a try. The line whistle isn't as ear-piercing as I'd expected it to be so shorted turns could be an issue.

Thanks, Dave.