I want some 2v sealed lead acid batteries for a project, to drive the
heaters of some vacuum tubes which need 1.5v at 2 amps. At present I'm
using 6v batteries with big dropper resistors. I haven't investgated a
voltage regulator yet, though this would be a good idea.
I have a charger which can be set for 2.44v, and regular intervals up
to 6.88v (and beyond). If and when I get 2v batteries, can they be
charged at 2.44v? andy

Eusebius wrote:
I want some 2v sealed lead acid batteries for a project, to drive the
heaters of some vacuum tubes which need 1.5v at 2 amps. At present I'm
using 6v batteries with big dropper resistors. I haven't investgated a
voltage regulator yet, though this would be a good idea.
I have a charger which can be set for 2.44v, and regular intervals up
to 6.88v (and beyond). If and when I get 2v batteries, can they be
charged at 2.44v? andy

Wouldn't you be better off using single C or D cells? It's probably
what the valve heaters were originally designed for.

You might even get away with NiMh cells.

--
Chris Green

On 9 Jan 2006 09:20:03 GMT, wrote:

Wouldn't you be better off using single C or D cells? It's probably
what the valve heaters were originally designed for.

Depending on the age of the valves they are much more likely to be
designed to run off a single lead acid cell of 2v nominal.

For the OP visit www.cpc.co.uk and put "cyclon" in the search box.

--
Cheers
Dave. pam is missing e-mail

Dave Liquorice wrote:
On 9 Jan 2006 09:20:03 GMT, wrote:

Wouldn't you be better off using single C or D cells? It's probably
what the valve heaters were originally designed for.

Depending on the age of the valves they are much more likely to be
designed to run off a single lead acid cell of 2v nominal.

Very old B4 and similar valves, yes, but the more modern DF series of
B7G and B9A based valves were surely 1.4 volts weren't they? The OP
did say 1.5 volts rather than 2.0 volts.

--
Chris Green

On Mon, 9 Jan 2006 15:53:45 UTC, wrote:

Very old B4 and similar valves, yes, but the more modern DF series of
B7G and B9A based valves were surely 1.4 volts weren't they? The OP
did say 1.5 volts rather than 2.0 volts.

Yes, by definition, if it used the European numbering system and began
with D, it was 1.4v for the filament/heater. Designed to run off dry
cells (I had a radio with those for years...a portable too!).

--
The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
Avenue Supplies, http://avenuesupplies.co.uk

Yes, by definition, if it used the European numbering system and began
with D, it was 1.4v for the filament/heater. Designed to run off dry
cells (I had a radio with those for years...a portable too!).

The valves are 26 - american type, and yes each is 1.5v at 1 amp. Not
the usual radio valves, which were more like 0.1 Amp. You could use D
cells for those. And yes, the European valves were often 1.4v like 3A5,
1LE3, DC90, DC93, DC96. DC96 had only 30mA of filament current.
The CPC link was absolutely right - probably the lowest prices. Looked
them up in my catalogue, then phoned the supplier. Cyclons (2v) should
be charged at 2.35v, and can be done so in a single stage - just needs
a very smooth supply of about 1% ripple and capable of 2 amps according
to them. Sounds like a DIY power supply would do this.

You might even get away with NiMh cells.

Hello - Depends how many you mean - remember we're talking 2 amps at
1.5v. NiMH are 2.8Ah. I tried them - they ran down almost immediately.
I think Cyclon 2v are the way to go.

Eusebius wrote:
You might even get away with NiMh cells.

Hello - Depends how many you mean - remember we're talking 2 amps at
1.5v. NiMH are 2.8Ah. I tried them - they ran down almost immediately.
I think Cyclon 2v are the way to go.

Not if you go for D size NiMh or NiCd cells, NiMh can be up to 11Ah
for a single D cell. I did explicitly say C or D size cells.

--
Chris Green

Eusebius wrote:

Yes, by definition, if it used the European numbering system and began
with D, it was 1.4v for the filament/heater. Designed to run off dry
cells (I had a radio with those for years...a portable too!).

The valves are 26 - american type, and yes each is 1.5v at 1 amp. Not
the usual radio valves, which were more like 0.1 Amp. You could use D
cells for those. And yes, the European valves were often 1.4v like 3A5,
1LE3, DC90, DC93, DC96. DC96 had only 30mA of filament current.
The CPC link was absolutely right - probably the lowest prices. Looked
them up in my catalogue, then phoned the supplier. Cyclons (2v) should
be charged at 2.35v, and can be done so in a single stage - just needs
a very smooth supply of about 1% ripple and capable of 2 amps according
to them. Sounds like a DIY power supply would do this.


I dont have a direct answer, but a few thoughts...

1A heater current is huge for filament valves: are these indirect
heated valves by any chance? If so, you can put muck through them quite
happily. A chopper to deliver the 6v at 1/16th duty cycle would work.
No way could you do that with direct heated filaments of course.

Any lead acid can be converted to gel cell by mixing the right stuff
into the electrolyte and pouring it back in. Trying to think, sodium
silicate?

Finally your local lead acid battery manufacturer could always provide
a cell to order.


NT

Hello Chris:
Not if you go for D size NiMh or NiCd cells, NiMh can be up to 11Ah
for a single D cell. I did explicitly say C or D size cells.

Cripes - 11Ah in a D cell! I had no idea - do you have a reference I
could look at? The Cyclon D cells are 2.5Ah. - seems about typical in
my cursory experience of NiMHs. 11Ah would be another story.

Eusebius wrote:

Cripes - 11Ah in a D cell!

or 12Ah http://www.thomas-distributing.com/c...-batteries.php

you might even find an quivalent 4/3D cell, presumably of 16Ah ...

Cripes - 11Ah in a D cell! or 12Ah http://www.thomas-distributing.com/c...-batteries.php

Well, this re-writes the text book. I have a Maplins NiMH charger which
takes 4 D cells. I wonder if it would charge 4 of the 12Ah ones?

Eusebius wrote:
Cripes - 11Ah in a D cell! or 12Ah http://www.thomas-distributing.com/c...-batteries.php


Well, this re-writes the text book. I have a Maplins NiMH charger which
takes 4 D cells. I wonder if it would charge 4 of the 12Ah ones?

Try it! Report back in a year or so....

http://uk.farnell.com/jsp/endecaSear...U=147180&N=401


Eusebius wrote:
I want some 2v sealed lead acid batteries for a project, to drive the
heaters of some vacuum tubes which need 1.5v at 2 amps. At present I'm
using 6v batteries with big dropper resistors. I haven't investgated a
voltage regulator yet, though this would be a good idea.
I have a charger which can be set for 2.44v, and regular intervals up
to 6.88v (and beyond). If and when I get 2v batteries, can they be
charged at 2.44v? andy

Eusebius wrote:
Hello Chris:
Not if you go for D size NiMh or NiCd cells, NiMh can be up to 11Ah
for a single D cell. I did explicitly say C or D size cells.

Cripes - 11Ah in a D cell! I had no idea - do you have a reference I
could look at? The Cyclon D cells are 2.5Ah. - seems about typical in
my cursory experience of NiMHs. 11Ah would be another story.


Just do a Google search for "NiMh D" and you'll find lots of them. I
found the 11Ah ones at www.mahaenergy.com, that's an American site but
the Maha (Powerex) cells and chargers are widely available in the UK.

--
Chris Green

In article .com,
Eusebius wrote:
I want some 2v sealed lead acid batteries for a project, to drive the
heaters of some vacuum tubes which need 1.5v at 2 amps. At present I'm
using 6v batteries with big dropper resistors. I haven't investgated a
voltage regulator yet, though this would be a good idea.
I have a charger which can be set for 2.44v, and regular intervals up
to 6.88v (and beyond). If and when I get 2v batteries, can they be
charged at 2.44v? andy
891506@@@@&BV_EngineID=ccckaddgjlgfjdkcefeceefdffh dfij.0&cacheID=uknetscape&callingPage=/jsp/browse/search.jsp&catoid=-1600760149&stockNo=2651947&name=SiteStandard

Or search for 2v cylindrical cells

--
*One tequila, two tequila, three tequila, floor.

Dave Plowman London SW
To e-mail, change noise into sound.

thanks for all the references - The 9Ah NiMH seem to be about £15 in
RS. That's about double the price of 8Ah Cyclons, though the cyclons
are bigger. Economically seems like Cyclons are the way to go.

On 8 Jan 2006 09:24:23 -0800, "Eusebius"
wrote:

I want some 2v sealed lead acid batteries for a project, to drive the
heaters of some vacuum tubes which need 1.5v at 2 amps. At present I'm
using 6v batteries with big dropper resistors. I haven't investgated a
voltage regulator yet, though this would be a good idea.
I have a charger which can be set for 2.44v, and regular intervals up
to 6.88v (and beyond). If and when I get 2v batteries, can they be
charged at 2.44v? andy

In addition to the online sources, model shops - as in proper model
shops that sell radio control planes etc - sell them as the power
source for engine glow plugs.

MJ