Newbie with Bush TV22 - UK Vintage Radio Repair and Restoration Discussion Forum

Petedox · 25th Feb 2020, 5:34 pm

Hi, I've been a lurker for some time, but have finally joined up!

I've mainly been building valve amps in the past, and refurbishing Quad and Leak stuff plus a few old radios etc, but really wanted a different challenge (and perhaps re-visit the days of my TV apprenticeship at the BRC Ultra plant in Gosport), so have bought a Bush TV22 to restore, picking it up tomorrow.

I'm amazed at the amount of stuff, and the expertise available on UKVR and have been trying to get up to speed as quickly as possible.

However my first question is: Are there any 'gotchas' or things I should be aware of as I gingerly take apart the TV22 apart for the first time? I'd appreciate any general advice!

Thanks, Pete

Ian - G4JQT · 25th Feb 2020, 8:13 pm

Hope the tube is OK. I've rebuilt two TV22s and a TV24. Line o/p transformer might be o/c and so might the blocking transformer. Both are rewindable by people on the forum if necessary. (I posted some LOPT data in one of the threads.) There are at last two versions of this TV so ensure you have the correct data for the one you have.

There is a link somewhere in one of the TV22 threads to a detailed complete rebuild I think. Maybe worth having a good search and read of those TV22/24 threads before you delve in. There will be plenty of help from those on here who may well have spent some time servicing them for real.

BTW, I think there is a waxed-paper capacitor hiding under a tag strip that is easy to miss.

Good luck.

FERNSEH · 25th Feb 2020, 10:33 pm

The only component that might cause some concern is the line output transformer, so before any attempt to power up the set to the mains the now well known drying out procedure should be applied. Using a DC power source of 20 to 30 volts connect this between the anode of the EY51 EHT rectifier and the top cap of the line output valve. Leave the transformer in this condition over a period of several days to drive out any moisture in the windings.

Link to a recent TV22 restoration: https://www.vintage-radio.net/forum/...d.php?t=157811

Ian-G4JQT wrote:
"Hope the tube is OK. I've rebuilt two TV22s and a TV24. Line o/p transformer might be o/c and so might the blocking transformer. Both are rewindable by people on the forum if necessary. (I posted some LOPT data in one of the threads.) There are at last two versions of this TV so ensure you have the correct data for the one you have."

There is a later version of the TV22, the less common TV22A which has a completely redesigned timebase circuit. Easily identified because the line output stage is located at the left side of the upper chassis deck.

The will be plenty TCC 343 wax capacitors to replace.

DFWB.

Keith · 26th Feb 2020, 1:14 pm

Hi Pete,

Definitely a worthwhile project - I had great fun restoring mine:

https://www.vintage-radio.net/forum/...d.php?t=143583

First thing to check would be the CRT heater - I think CRT's are pretty well unobtanium. Hopefully your transformers will be in a better state than mine were (o/c frame oscillator and output).

Good luck
Keith

Petedox · 26th Feb 2020, 3:49 pm

Wow, thanks for quick response gents, and the links - plenty to digest over the next few days.

I've identified it as a TV22 Mk2 (chassis prefix 124, RF unit A22). It looks pretty unmolested. I'll hook up the DC source as you suggested Fernseh while it gets accustomed to its new surroundings.

I've just built a uTracer valve tester so may check the valves over and do a few cold checks on the transformers and CRT heaters in the meantime.

Thanks again!

25th Feb 2020, 5:34 pm	#1
Petedox Pentode Join Date: Feb 2020 Location: Waterlooville, Hampshire, UK. Posts: 200	Newbie with Bush TV22 Hi, I've been a lurker for some time, but have finally joined up! I've mainly been building valve amps in the past, and refurbishing Quad and Leak stuff plus a few old radios etc, but really wanted a different challenge (and perhaps re-visit the days of my TV apprenticeship at the BRC Ultra plant in Gosport), so have bought a Bush TV22 to restore, picking it up tomorrow. I'm amazed at the amount of stuff, and the expertise available on UKVR and have been trying to get up to speed as quickly as possible. However my first question is: Are there any 'gotchas' or things I should be aware of as I gingerly take apart the TV22 apart for the first time? I'd appreciate any general advice! Thanks, Pete

25th Feb 2020, 8:13 pm	#2
Ian - G4JQT Octode Join Date: Jun 2004 Location: Reading/Fakenham, UK. Posts: 1,323	Re: Newbie with Bush TV22 Hope the tube is OK. I've rebuilt two TV22s and a TV24. Line o/p transformer might be o/c and so might the blocking transformer. Both are rewindable by people on the forum if necessary. (I posted some LOPT data in one of the threads.) There are at last two versions of this TV so ensure you have the correct data for the one you have. There is a link somewhere in one of the TV22 threads to a detailed complete rebuild I think. Maybe worth having a good search and read of those TV22/24 threads before you delve in. There will be plenty of help from those on here who may well have spent some time servicing them for real. BTW, I think there is a waxed-paper capacitor hiding under a tag strip that is easy to miss. Good luck.

25th Feb 2020, 10:33 pm	#3
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Newbie with Bush TV22 The only component that might cause some concern is the line output transformer, so before any attempt to power up the set to the mains the now well known drying out procedure should be applied. Using a DC power source of 20 to 30 volts connect this between the anode of the EY51 EHT rectifier and the top cap of the line output valve. Leave the transformer in this condition over a period of several days to drive out any moisture in the windings. Link to a recent TV22 restoration: https://www.vintage-radio.net/forum/...d.php?t=157811 Ian-G4JQT wrote: "Hope the tube is OK. I've rebuilt two TV22s and a TV24. Line o/p transformer might be o/c and so might the blocking transformer. Both are rewindable by people on the forum if necessary. (I posted some LOPT data in one of the threads.) There are at last two versions of this TV so ensure you have the correct data for the one you have." There is a later version of the TV22, the less common TV22A which has a completely redesigned timebase circuit. Easily identified because the line output stage is located at the left side of the upper chassis deck. The will be plenty TCC 343 wax capacitors to replace. DFWB.

26th Feb 2020, 1:14 pm	#4
Keith Heptode Join Date: Jan 2003 Location: Tewkesbury, Gloucestershire, UK. Posts: 693	Re: Newbie with Bush TV22 Hi Pete, Definitely a worthwhile project - I had great fun restoring mine: https://www.vintage-radio.net/forum/...d.php?t=143583 First thing to check would be the CRT heater - I think CRT's are pretty well unobtanium. Hopefully your transformers will be in a better state than mine were (o/c frame oscillator and output). Good luck Keith __________________ Keith Yates - G3XGW VMARS & BVWS member http://www.tibblestone.com/oldradios/Old_Radios.htm

26th Feb 2020, 3:49 pm	#5
Petedox Pentode Join Date: Feb 2020 Location: Waterlooville, Hampshire, UK. Posts: 200	Re: Newbie with Bush TV22 Wow, thanks for quick response gents, and the links - plenty to digest over the next few days. I've identified it as a TV22 Mk2 (chassis prefix 124, RF unit A22). It looks pretty unmolested. I'll hook up the DC source as you suggested Fernseh while it gets accustomed to its new surroundings. I've just built a uTracer valve tester so may check the valves over and do a few cold checks on the transformers and CRT heaters in the meantime. Thanks again!