Making of an HT battery - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

David G4EBT · 23rd Feb 2011, 11:26 pm

Quote:

Originally Posted by mickjjo

Attached is an advert from Popular Wireless magazine, Feb 1934, for "Grosvenor" HT batteries. Allowing for inflation, yours may well work out cheaper to make.

Regards, Mick.

It surely does!

17/6p in 1934 equates to £42.00 in 2011!!

David

(Neat idea to use the brass tubes for voltage tappings, rather like the grid bias batteries of yore).

Herald1360 · 24th Feb 2011, 12:27 am

How about the Voltokil 135?

Or maybe AA90?

24th Feb 2011, 2:27 pm

Cover made...

Chindit · 24th Feb 2011, 3:11 pm

Well done merlinmaxwell! You've made a really neat job of this.

As a newcomer to this forum, it is great to see that others enjoy making HT batteries as well! I have been a keen collector of battery operated sets for many years; it is great fun to be able to use them exactly as intended - fully portable!

I have restored old B101, B107, B114, B126, B136 and B141 Ever Ready batteries by using chains of PP3s - the smaller HT batteries require them to be soldered together in a stack but in the larger batteries (B107 - Ever Ready Model N, B136 - Sky Queen and B141 - Sky Casket/ Captain/ Baronet) they can be joined simply by clipping them together using their own contacts to form a flat pack of ten batteries in two slightly staggered rows of 5 each. This way, you only need a single connector stud for each end!

Several years ago, I built an Ever Ready 'Portable 56' HT battery for an Ekco B53 receiver. I employed the same methodology of using individual 1½ volt cells to deliver the 136½ volts required, however, as the Portable 56 was very large battery I had room to simply clip the cells into an array of 9 volt holders. I fitted a small chassis mounted fuseholder inside the battery along with a 100mA fuse for safety.

Best wishes,
Colin.

TuningIndicator · 24th Feb 2011, 7:39 pm

BRILLIANT!

26th Feb 2011, 4:52 pm

A quick flick of the AVO on the 12V tapping gave over 10A, assume it will give 10A S/C at 135V that gives an internal resistance of 13.5 ohms. For maximum power delivery Zo = Zi therefore with a 13.5 ohm load, I=5A V=67.5V and P=337.5W in the load. Quite a lot, what was the average internal impeadance of a 1930's HT battery I wonder.

fusewire · 26th Feb 2011, 11:14 pm

hi, i made one of those a while ago know i use 9v pp3, ive just baught some jerman varta aa batts for 58p for 4 from local super market, oh theirs not much of a kick from 90v i just touched my 110v batt erray actually its about 120, it was just a tickle low current i suppose, fusewire.

26th Feb 2011, 11:41 pm

The human body is a bag full of salty water, a few kilo ohms resistance, it's the skin that stops us being killed by a few 10's of volts. There is some data on the likely effect of voltage, current and type of contact (wet/dry hands AC/DC etc.) it came, somewhat worringly, from the US penal service.

matthewhouse · 26th Feb 2011, 11:42 pm

These set-ups must have a reasonable current available, as they will easily light standard GLS lamps, though probably not for long. The shock from a DC battery will feel different to that of an AC supply of the same voltage.

McMurdo · 27th Feb 2011, 12:01 am

Dont forget that John Logie Baird was nearly killed joining up torch batteries

27th Feb 2011, 12:03 am

Quote:

These set-ups must have a reasonable current available

10A for mine.

batterymaker1 · 27th Feb 2011, 4:38 am

Killer---love the name!

dennishoy · 27th Feb 2011, 4:22 pm

When I tried to solder some wires to AA cells, one of them exploded.

I was Ok, but the crack was deafening and my ears took a minute or two to recover. I haven't tried it since.

Perhaps this is why these cells are supplied with solder tabs where needed rather than try to do it yourself.

Herald1360 · 27th Feb 2011, 5:37 pm

Were they alkalines or rechargeable NiCd / NiMH types? - those warn against soldering wires.

Never seen a tagged primary cell except for Li types.

dennishoy · 1st Mar 2011, 7:11 pm

They were Ni-Mh AA size with no solder tag.
The problem occured as I was tinning the base to take a wire.

If you search a popular auction site for 'AA tab', you will find some green Ni-Mh cells with tags. (note TAB for the search, not TAG).

I suggest you use these rather than try to solder wires to Ni-Mh cells.
I've more recently used the blue-covered Li-Ion ones further down the page from the USA (branded TENERGY) and they are excellent. The tags have a fairly weak spot weld, so don't bend them through a too-tight angle.

AlanBeckett · 1st Mar 2011, 7:15 pm

Commercial sell stacks are usually spot or laser welded using thin metal strips to connect the cells together.
Alan

24th Feb 2011, 12:27 am	#22
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,536	Re: Making of an HT battery How about the Voltokil 135? Or maybe AA90? __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

24th Feb 2011, 2:27 pm	#23
Guest Guest Posts: n/a	Re: Making of an HT battery Cover made... Attached Thumbnails

24th Feb 2011, 3:11 pm	#24
Chindit Tetrode Join Date: Feb 2011 Location: Bishop Auckland, County Durham, UK. Posts: 97	Re: Making of an HT battery Well done merlinmaxwell! You've made a really neat job of this. As a newcomer to this forum, it is great to see that others enjoy making HT batteries as well! I have been a keen collector of battery operated sets for many years; it is great fun to be able to use them exactly as intended - fully portable! I have restored old B101, B107, B114, B126, B136 and B141 Ever Ready batteries by using chains of PP3s - the smaller HT batteries require them to be soldered together in a stack but in the larger batteries (B107 - Ever Ready Model N, B136 - Sky Queen and B141 - Sky Casket/ Captain/ Baronet) they can be joined simply by clipping them together using their own contacts to form a flat pack of ten batteries in two slightly staggered rows of 5 each. This way, you only need a single connector stud for each end! Several years ago, I built an Ever Ready 'Portable 56' HT battery for an Ekco B53 receiver. I employed the same methodology of using individual 1½ volt cells to deliver the 136½ volts required, however, as the Portable 56 was very large battery I had room to simply clip the cells into an array of 9 volt holders. I fitted a small chassis mounted fuseholder inside the battery along with a 100mA fuse for safety. Best wishes, Colin.

24th Feb 2011, 7:39 pm	#25
TuningIndicator Retired Dormant Member Join Date: Aug 2010 Location: Sussex, UK. Posts: 161	Re: Making of an HT battery BRILLIANT!

26th Feb 2011, 4:52 pm	#26
Guest Guest Posts: n/a	Re: Making of an HT battery A quick flick of the AVO on the 12V tapping gave over 10A, assume it will give 10A S/C at 135V that gives an internal resistance of 13.5 ohms. For maximum power delivery Zo = Zi therefore with a 13.5 ohm load, I=5A V=67.5V and P=337.5W in the load. Quite a lot, what was the average internal impeadance of a 1930's HT battery I wonder.

26th Feb 2011, 11:14 pm	#27
fusewire Retired Dormant Member Join Date: Feb 2011 Location: Moreton, Wirral, Merseyside. Posts: 27	Re: Making of an HT battery hi, i made one of those a while ago know i use 9v pp3, ive just baught some jerman varta aa batts for 58p for 4 from local super market, oh theirs not much of a kick from 90v i just touched my 110v batt erray actually its about 120, it was just a tickle low current i suppose, fusewire.

26th Feb 2011, 11:41 pm	#28
Guest Guest Posts: n/a	Re: Making of an HT battery The human body is a bag full of salty water, a few kilo ohms resistance, it's the skin that stops us being killed by a few 10's of volts. There is some data on the likely effect of voltage, current and type of contact (wet/dry hands AC/DC etc.) it came, somewhat worringly, from the US penal service.

26th Feb 2011, 11:42 pm	#29
matthewhouse Octode Join Date: Jul 2006 Location: Willand, Devon, UK. Posts: 1,023	Re: Making of an HT battery These set-ups must have a reasonable current available, as they will easily light standard GLS lamps, though probably not for long. The shock from a DC battery will feel different to that of an AC supply of the same voltage.

27th Feb 2011, 12:01 am	#30
McMurdo Dekatron Join Date: Jun 2009 Location: Staffordshire Moorlands, UK. Posts: 5,275	Re: Making of an HT battery Dont forget that John Logie Baird was nearly killed joining up torch batteries __________________ Kevin

27th Feb 2011, 4:38 am	#32
batterymaker1 Heptode Join Date: Apr 2006 Location: Indianapolis, Indiana, USA. Posts: 674	Re: Making of an HT battery Killer---love the name! __________________ Just playing with high voltage....

27th Feb 2011, 4:22 pm	#33
dennishoy Retired Dormant Member Join Date: Nov 2010 Location: Hampshire, UK. Posts: 167	Re: Making of an HT battery When I tried to solder some wires to AA cells, one of them exploded. I was Ok, but the crack was deafening and my ears took a minute or two to recover. I haven't tried it since. Perhaps this is why these cells are supplied with solder tabs where needed rather than try to do it yourself.

27th Feb 2011, 5:37 pm	#34
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,536	Re: Making of an HT battery Were they alkalines or rechargeable NiCd / NiMH types? - those warn against soldering wires. Never seen a tagged primary cell except for Li types. __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

1st Mar 2011, 7:11 pm	#35
dennishoy Retired Dormant Member Join Date: Nov 2010 Location: Hampshire, UK. Posts: 167	Re: Making of an HT battery They were Ni-Mh AA size with no solder tag. The problem occured as I was tinning the base to take a wire. If you search a popular auction site for 'AA tab', you will find some green Ni-Mh cells with tags. (note TAB for the search, not TAG). I suggest you use these rather than try to solder wires to Ni-Mh cells. I've more recently used the blue-covered Li-Ion ones further down the page from the USA (branded TENERGY) and they are excellent. The tags have a fairly weak spot weld, so don't bend them through a too-tight angle. Last edited by dennishoy; 1st Mar 2011 at 7:24 pm.

1st Mar 2011, 7:15 pm	#36
AlanBeckett Rest in Peace Join Date: Dec 2008 Location: Burton upon Trent, East Staffordshire, UK. Posts: 1,686	Re: Making of an HT battery Commercial sell stacks are usually spot or laser welded using thin metal strips to connect the cells together. Alan