Introduction and questions re TV22

[Geoff 555]

Hello I have just joined and this is the first in the line of quite a few questions I suspect. A little introduction is probably in order. About 90% of my working life has been about mechanical things and I know very little about electronics, I can reconise a valve (like a light bulb), a condenser (a sticky yellow thing) and a resistor (has pretty coloured bands).

I have been retired for some years and am not very mobile (nerve damage) and this is something to occupy my brain such as it is.

I have unearthed a Bush TV22 and wish to restore it to working condition (to keep and ‘hand on’ when the time comes). It seems to be complete and it would be a great help to have some basic voltages to see what is going on. Tube base, HT etc. I would need a pointer as to where things are please. All the rubber covered wiring is going to have to be
replaced as the insulation has gone. I don't know the condition of the tube, the line output tx looks rather unwell to say the least.

I have tried to read some of the threads on the 22 but to be honest they are beyond me.
I thank you for any help/advise you may be able to give, it will be much appreciated.

Cheers.

Geoff 555.

Sorry for the long post.

[Steve_P]

If you look up top, there's a panel to click for service data. The TV22 is there. You'll need that!

Get a meter (Maplins do one), screwdrivers, pliers, etc.

You need to change all the caps. Especially the ones in the PSU, Line and Frame Timebases. The LOPT may be OK, but if not it can be rewound. The tube should be OK, as long as it's not gone white or lost any phosphors. It may come straight up, it may need to be ran for a bit to wake it up.

Good sets these. Worth a bit too.

To run it, you need a standards converter, as 405 Television closed in 1985. The best ones are made by Darryl Hock -

http://converter.home.comcast.net/~converter/

You can run without one for now though. We're here all the time and if you get stuck...ASK.

Cheers,

Steve P

[paulsherwin]

It might be an idea to learn the ropes restoring an old radio rather than a TV. Old tellies are complex things containing very high voltages. A radio will contain similar technology but will be much simpler so will be easier to understand. You can buy a suitable set for restoration on eBay for a fiver or so (look for collection only items within 10 miles of your postcode) or another forum member may have something suitable.

Once you've learnt the basics, the TV22 will be much less daunting. You're likely to make a better job of restoring it too.

Good luck, Paul

[evingar]

Welcome Geoff.

the line output tx looks rather unwell to say the least.

Appearances can be deceptive with these. They can look dreadful, with bits of pitch flaking off (etc) but be perfectly OK - You will have to get a fair way into the restoration before you will know whether that and the tube are OK

Paul's suggestion is good, a radio is probably a good way to ease your self into this hobby - 50s wooden sets ("woodies") are pretty cheap.

Best of luck

Chris

[SWB 18]

Hello,

You can find some TV22 service data here http://www.thevalvepage.com/tvmanu/bush/bush.htm
which may help you to 'get to know' your set.

Regards,

Phil.

[Geoff 555]

Thank you for the advise, I will get the service sheets and have a AVO 8 that I used in work. I am aware that there are some high voltages waiting to bite and being a coward will be very careful.Ta for the warning. I have owned a McMicheal 137 for 41 years and I havnt managed to kill it or it me and it works quite well.About 6 months ago I changed the drive cord to a proper one rather than fishing line, that was fun.
I have been informed that all electrical things contain a magic ingreedient called 'smoke' and if you let it out, they dont work any more. We shall see.

Thanks again.
Cheers.
Geoff 555.

[Geoff 555]

Hello everyone time for an update I think. Apart from the 'wanted' section I think the best way to tackle this is to keep all the questions on one thread, otherwise it's going to get really confusing and I wont remember where things are.If this is OK I will carry on, if not please let me know.(It's a memory thing, full of holes.)

There are only a couple of questions and they are about capacitors in particular C28 which is a 0.75 mf 250 Volt AC wax very melted yellow type. What would be a suitable 'type' of replacement ( poly something??) and the biggest stumbling block is having looked at CPC all the caps are for DC, is there a DC equivalent voltage for a AC, if you see what I mean. IE. 1000V DC an OK replacement for 250AC.
1 end of the cap goes to the mains dropper via a 1.2K res. the other end to various things. the brightness control via a 56K res. and possibly the HT + if I'm reading this right.(TBH It's more guessing than reading.)
Thanks chaps, sorry this is going to be a long thread, thanks for being patient. It's going to be a jolly steep learning curve. I am not going to be beaten and with you generous help another one (22) will survive.
Cheers.
Geoff 555.
Ta for info from the component section for web address's.

[ppppenguin]

Generally a 1000VDC cap will be fine with 250VAC. Rather better is to heed others advice and fit an X2 rated cap. These are designed for mains related applications and are the best choice here. You may well find a suitable cap in a scrap computer power supply. You will see X2 marked somewhere on the case. There may or may not be a voltage rating but be assured that it's designed for the job.

[Panrock]

For what it's worth, there is to be a fully illustrated blow-by-blow account of the restoration of a TV22 appearing on my site in a few weeks. It will be in the same format as the recent Baird restoration.

You and others might find this helpful. There are a lot of TV22s about - and being restored.

Steve

[Geoff 555]

Thank you very much Panrock ,I await the write up with bated breath.
Cheers.
Geoff.

[Geoff 555]

Hello all time for a couple ( more actually) of questions, recapping is slowly taking place. In preparation for when it's time to give it some power what is the best way to start it gently, I dont have a variac and to be honest cant afford one. Light bulb in series with mains ??
Which way do the pins run on the tube base and what should I expect?

I wont be able to attempt to rewind the LOPT so who do I contact about having it rewound. The pitch round the bottom has melted and dripped down and the pitch by the EY51 has dropped off and exposed the windings, I will give it a try but it does look as if it's died.

I have seen some pictures of 22's and note that the ion trap magnet seems to be about 5 o/c mine is about 11 o/c as a starting point where should it be.


Finally ,for now anyway, does anyone know of a tube original or crm 192 (I think that is correct. ) I would buy a complete set if necessary, I know that mine has gone as it has cracked from the base to underneath the scan coils.

Thank you for time and trouble.

Best wishes.

Geoff 555.

[Steve_P]

Yes, bulb starters will do. Look here: http://www.vintage-radio.com/projects/lamp-limiter.html

The tube base : there will either be a gap in the pins or a pip to locate the base plug. You count round from this clockwise.

Mike Barker (murphymad) or Ed Dinning can both rewind transformers.

As far as the Ion Magnet - just adjust for a picture. You'll find a picture here: www.oldtellys.co.uk and click on Monochrome Tubes.

Cheers,

Steve P.

[Geoff 555]

Thank you very much for the information and the quick reply, great. I feel a visit to the shops coming on, I havnt done so much reading in years, it's a pity I've only got a five second memory!!

Cheers.

All the best.
Geoff 555.

[Geoff 555]

Hello all. I think I have got as far as I can get without getting into serious trouble so I am asking for your opinions and help please.
I was convinced that the tube was cracked as there is a mark that I can get my thumb nail in. It may well prove to be US anyway,damn it.
It has new caps throughout except the mica ones and a new set of valves, I havnt changed the EY 51 because of the state of the LOPT.
All the heaters light up, quite brightly** and there is a show of light in the EY51.There is EHT. I cant hear any line whistle, what I mean is it may be there but I am not able to hear it.
There is a crackle if I touch the aerial socket with a screwdriver.

Tube base voltages.
pin 1. heater.
pin 12 heater. voltage 3-1 V.

Pin 2 0 - 86 V changes with brightness control.

Pin 10 Anode?? connected to metrosil. 176 V.

Pin 11 Cathode?? 90 - 87 V varies slightly with rotation of contrast control.

No screen illumination what so ever.

** tube heater can only be seen with the lights off.

I did try the metrosil 'mod' with a couple of diodes and r's etc. and pin 10 dropped to 103 V. BUT I wasnt quite sure how to connect it up that is when I decided that I was getting right out of my depth and stopped.

To recap I know next to nothing about TV ( ok being honest electronics etc.) so it would be a great help if you could kindly keep thing simple please.

With many thanks.
Cheers.
Geoff.555

[Steve_P]

If the EY51 is lit, then the Line Timebase is working. Try rocking the Line Hold control about and see if you get to hear anything, then set it midway.

The Metrosil mod is here : http://freespace.virgin.net/andy.valve/techa.htm

3.1 Volts on the heater is OK for now. Try moving the ion trap about if it's been shifted previously.

Cheers,

Steve P.

[Tazman1966]

Hi Geoff.

The fact that the EHT rectifier is alight is a good sign. The line oscillator must be working but may be way too high off frequency and that's why you can't hear it? Just a thought!

Regards,

Edit post: Posted same time as Steve P.

[Geoff 555]

OK gentlemen thank you.Rocking the line hold control makes no difference that I can tell.( but remember that I am unable to hear it anyway.)
The ion trap magnet was hanging loose when I got the set and I have tried it in every position possible ,I think.
The site was the one for the metrosil ,thanks, but what I couldnt work out was how to connect it,according to the sheet I have got, and I am not convinced it's the right one.(shows 8 pins on the crt) one side of the original metrosil is connected to the LOPT and on to a 300pf then a R and through to the horizontal control.

The other side is connected to a 0.1 mf C which is earthed and the crt.

The mod has diodes that connect to the lopt so I take it the original metrosil is chopped at the junction of where it connects to the LOPT and the 300pf ,
Now to where I get really confused , the other side of the metrosil connects to a 0.1 mf ( the other side of the C connects to earth.) the mod also shows a 0.1 mf ,so is there 2 C's?? there is also a connection to earth , through a 1 meg R.

Sorry if it's long I have tried to explain it as best I can.

Many thanks.
Cheers.
Geoff 555

[Steve_P]

Right.

1: Chop out the Metrosil.
2: The diodes shown go at the LOPT end, where the Metrosil was.
3: The two resistors go in series with the other end of the diodes and Chassis.
4. The junction of the two resistors is where you take off the lead to Pin 10 of the CRT.
5. The 0.1uF Cap (just one!) goes between the CRT Pin 10 and Chassis.

Cheers,

Steve P.

[dominicbeesley]

I spent ages trying to get a raster thinking all was lost and it was the ion trap. Try it in every conceivable position - not just where its supposed to be! I think mine had gone a bit weak over time so needed a lot of moving. Also you could try marking it with an arrow so you know where it came from and try taking it off and turning it round. If it was hangining off somebody may already have fiddled with it.

If that still doesn't work check to see if the magnet in the trap still works - not sure how but I'm sure there must be a simple check!

All the time you're fiddling with the trap make sure you've got a mirror hand watch the screen while you fiddle the magnet, it can be quite ellusive finding the "sweet spot". Good luck!

[Geoff 555]

Good morning gentlemen or is it afternoon. I think it's time to stop, I have tried the metrosil mod and as before it kills the voltage to 90V.
Put the old one (metrosil) in and lifted the tube end off the tag board and put a 0.1mf from it to earth, result a very momentary reading of 280V dropping back to 190V.
Trader sheet numbers.
C31 from the metrosil to earth does not appear to be earthed, neither does C25 the one next to it this is why I did the above. Time perhaps to take it to someone that can see what is going on.
When I recapped it I was very careful and even took pictures so I dont think it's anything that I've done But there is aways that chance.
What concerns me is the 3.3V across the heater and it's very dull compared to the other heaters, which are, to me very bright.
With the volume turned up if I swing the horizontal hold then a slight tone change can be heard. Thank you yet again for your help.

Cheers.
Geoff.555