UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > Components and Circuits

Notices

Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets.

Closed Thread
 
Thread Tools
Old 28th Jun 2011, 3:35 pm   #1
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Battery box and socket details.

I'm designing some battery valve stuff and I know little about the Traditional 1950s battery packs.
I remember the WS 88 that fitted an Ammunition pouch and 1.5V + 90V battery in the other pouch.
I remember a "Lady Margaret" or similar portable that I fitted a mains eliminator into when I was 11 or 12. Also a wooden cabinet radio that took a battery pack.

Is there any site or list of standard battery packs and sizes? Maybe even with package artwork I could print?

Additionally I want to adapt internals of package and connector.

My needs
Possibly 3 off identical 48V nominal rechargeable packs with 1.3V NiMH for heaters in one "suitcase" radio. Each of the 3 LT batteries would power 1/3rd of the filament power. On Receive the 3 x 48V HT are in parallel, and on Transmit two of the HT packs go in series with main 48V HT to give TX PA HT of 140V nominal. The 2 or 4 PA valves are used as audio PA on receive at 48V. The push-pull audio transformer drive connections will have 2 x RF chokes in series and provide 140V to 150V nominal HT to PA on transmit. The RF from PA will be to RX/TX relay via 2 x 470pF or 1nF capacitors to a common-mode choke/transformer as balun so it will not affect audio.

The end point of the NiMH is just under 1V and absolutely fully charged are near 1.47V (no load) dropping at once to about 1.35V under load, about 1.25V average as they discharge down to 1V. Some datasheets / experts claim 0.9V or even 0.8V is endpoint, but 1V is "safer" to avoid a weakest cell getting "reverse charged".

AA: 1800mAH to 2200mAH capacities are more reliable. The 2500mA to 2700mA types self discharge fast sometimes in a week and last for less cycles. Eneloop are supposed to be best.
AAA: 700mAH more reliable in long term than 1000mA
PP3: 180mAH is realistic. The 200mA or higher may be not as good, or optimistic.
C: 3500mAH is likely OK, 4000mAH? I don't know. If it's 2500mA and light suspect is really an AA.
D: Most are actually C cells or even AA. Only really a D cell if 4500mAH

A modern NiMH C cell is likely not much lower capacity than an old NiCd true D cell. A Nominal 24V military set may use 19 x D size NiCd. Only 18 x C size NiMH needed to give similar volts and capacity.

So any comprehensive list of dimensions and voltages of LT + HT dry battery packs?

I think possibly 65V rather than 90V for some radios. Were only hearing aid valves 22.5V, no Radios?
Telecoms uses nominal -48V since forever. It's actually about 40V to 56V really as "lead acid" derived. Real float charged Lead Acid Car batteries are 13.5V to 14.2V, not 12V. Use below about 10.5V on a 6 cell battery usually means the death of it.

NiCd and NiMH doesn't mind complete discharge, but only if all cells equally, thus with a battery of multiple cells the one to reach 0V 1st gets destroyed by reverse charge from the others. Thus on NiMH a nominal 48V pack using 40 cells is 40V at discharge limit to average 48V about 54V "fresh" and maybe nearly 60V on trickle charge. It might be an idea to limit end point to about 42 or 43V and for charger to supply nominal 48V as well as charge batteries "out of circuit" to have longer battery pack life and more consistent operation.

The problems of cell matching and charge limits are MUCH more severe on Rechargeable Lithium technologies as discharge or charge beyond a certain point can result in catastrophic failure.

Most high capacity Lithium and NiMH batteries can't be kept on trickle charge. The NiMH the trickle charge can't be maintained when full like NiCd. That wears out the cell. If there is trickle current on NiMH once charged, it must not exceed the self discharge current.

Last edited by neon indicator; 28th Jun 2011 at 3:40 pm.
neon indicator is offline  
Old 30th Jun 2011, 2:23 pm   #2
ThePillenwerfer
Octode
 
ThePillenwerfer's Avatar
 
Join Date: Mar 2011
Location: Sheffield, South Yorkshire, UK.
Posts: 1,137
Default Re: Battery Boxes.

Try this:-

http://www.the-thompson-brown-family...eriesframe.htm

The artwork isn't up much but it does give the sizes.

- Joe
__________________
"Experts are only good at one thing: explaining why something will not work!"
ThePillenwerfer is online now  
Old 30th Jun 2011, 3:07 pm   #3
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

Thanks ThePillenwerfer, It's a good start!

I see there was 45V, so maybe I should pick that instead of 48V.

38 NiMH is 38V to 51V, maybe about 46V average
36 NiMH is 36V to 48.6, maybe about 43V average

Most 48V relays are rated 33.6V to 96V
24V relays take slightly less power and are cheaper, two x 2pco in series gives 4pco

Last edited by neon indicator; 30th Jun 2011 at 3:22 pm.
neon indicator is offline  
Old 30th Jun 2011, 3:39 pm   #4
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

I think I can just fit 3 rows of 6 staggered columns of 2 x AA NiMH total 36 cells in the B104 "45V" box. Close enough to 45V

for LT I want to use C size NiMH. What do people think of paralleling them? They are about 3500mAH each.
neon indicator is offline  
Old 30th Jun 2011, 3:55 pm   #5
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

Maybe AD4 for LT?
neon indicator is offline  
Old 30th Jun 2011, 4:13 pm   #6
ppppenguin
Banned
 
ppppenguin's Avatar
 
Join Date: Dec 2003
Location: North London, UK.
Posts: 6,168
Default Re: Battery Boxes.

Quote:
Originally Posted by neon indicator View Post
for LT I want to use C size NiMH. What do people think of paralleling them?
Not recommended. It may be theoretically possible but definitely not a good idea. They have very low internal impedance so large currents could flow between the cells. Some claim this is not a problem. I wouldn't want to find out the hard way unless it was essential to my application. Google nimh parallel for a wide range of views.

Also remember that your proposed NiMH HT battery is capable of producing very high currents compared to a dry battery. I would strongly recommend a fuse.
ppppenguin is offline  
Old 30th Jun 2011, 4:23 pm   #7
geofy
No Longer a Member
 
Join Date: Jun 2006
Posts: 1,799
Post Re: Battery Boxes.

Quote:
Originally Posted by neon indicator View Post
AA: 1800mAH to 2200mAH capacities are more reliable. The 2500mA to 2700mA types self discharge fast sometimes in a week and last for less cycles. Eneloop are supposed to be best.
AAA: 700mAH more reliable in long term than 1000mA
PP3: 180mAH is realistic. The 200mA or higher may be not as good, or optimistic.
I have no trouble with 2650mAh Mallory rechargable cells, I have two in an automatic tin opener which stay charged for months, opening lots of tins. Four in a Roberts R9903 radio which also last for ages.

And a 200mAh PP3 Uniross in my recently repaired R200 which plays all day.
geofy is offline  
Old 30th Jun 2011, 4:26 pm   #8
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

I have a military set with 18 x 3500mA NiMH C cells. A short on that as you say is as fun as a spanner dropped across a car battery!

I've always thought it's scary the way most Laptop battery packs have paralleled LiIon cells.

So I presume the trick is to have cells from same batch and charge level before paralleling them?

I think a bad idea to parallel cells that are not new.
neon indicator is offline  
Old 30th Jun 2011, 4:34 pm   #9
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

Quote:
Originally Posted by geofy View Post
I have no trouble with 2650mAh Mallory rechargeable cells, I have two in an automatic tin opener which stay charged for months, opening lots of tins. Four in a Roberts R9903 radio which also last for ages.
And a 200mAh PP3 Uniross in my recently repaired R200 which plays all day.
Are those Mallory AA size? They may be a "good" make. Certainly the Sanyo Eneloop have a good reputation.

Certainly there ARE lots of reports of higher capacity cells that self discharge rapidly. The worst ones I bought self discharge in less than 2 weeks.

If you are charging every 10 days or more often you wouldn't notice.

Also "some" cells labelled as high capacity cells are not actually, so obviously those don't have the problem I'm now suspicious of "own brand" cells, though oddly Maplin is trying to sell their own AA for 50% more than branded Energiser of same rating. €17 for 4 "own brand" AA seems madly expensive. Lidl and Aldi are cheap. But don't have them that often.
neon indicator is offline  
Old 30th Jun 2011, 4:47 pm   #10
richrussell
Heptode
 
richrussell's Avatar
 
Join Date: Jul 2008
Location: Selby, North Yorkshire, UK.
Posts: 975
Default Re: Battery Boxes.

Something else to consider are the radio controlled helicopter/aircraft LiPo batteries. Extremely high energy density, slow self discharge rate, and come in various voltages (mainly 7.4V and 11.1V though). Though you do need a specialised LiPo charger and of course if they get punctured they tend to burn/explode very violently.

Actually, yes, you're probably better off with NiMH
richrussell is offline  
Old 30th Jun 2011, 5:14 pm   #11
geofy
No Longer a Member
 
Join Date: Jun 2006
Posts: 1,799
Post Re: Battery Boxes.

Quote:
Originally Posted by neon indicator View Post
Are those Mallory AA size? They may be a "good" make. Certainly the Sanyo Eneloop have a good reputation..
Yes AA cells in both, the ones in the tin opener are in fact Eveready Energizer 2500mAh and get charged when I can no longer open my favourite baked beans, which is at least a couple of months.

If the Maplin ones are twice the price of the Energizer then get the latter, I am wary of own brands or cheap branded ones. If Mallory can't make cells then no one can, the only exception being the non-rechargeable Ultra range which seem to be prone to leakage I get the Plus range of Alkalines.
geofy is offline  
Old 30th Jun 2011, 6:29 pm   #12
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

I made up the AD4 (in paper) correct size. It's huge. must have been 6 x D cells.

Was thinking maybe B114 with 2xC cells in parallel (selected new and measured) and 38 x AAA cells. (38V to 51V, about 46V average). Three of these will sit along back/bottom almost full width of the suitcase. The HT paralleled by diodes and denergised relays. In Transmit the 45V part of circuit is fed from one box and the other two added in series for 3 x 45 = 135V TX P.A. (1p24b). The valves heaters in 3 matched sets to connect separately to the LT batteries, so that's 6 x 3500mAH heater capacity.

But the AAA are nearly as expensive as AA, so I will go with 3 rows of 6 staggered columns of 2 x AA NiMH total 36 cells in the B104 "45V" box. Seems same size as B114, so three fit suitcase well. The RX will then have 3 x 2500mAH @ 43V nominal (49.5V peak) = 7500mAH HT, 35V approx "flat" and thus TX mode will be 2500mAH 130V Nominal 150V peak. About 108V near "flat", tapped at 43V nominal.

The RF PA valves used for RX loudspeaker Audio PA at 43V nom.

And just use regular battery holders for the C or D cell LT supply.

I see some cheap 3000mAH NiMH on eBay. I don't know that I really believe there are 3000mAH AA cells. The C cells are usually 3,500mAH. Some 4000mAH.

In any case I will use bench PSU till radio finished as 108 x AA NiMH is somewhat of an investment! (x12 the capacity of using PP3s though).

I have a nice 8" speaker and will cut the Pye rising sun + clouds as the grill.
What you think?
neon indicator is offline  
Old 30th Jun 2011, 6:42 pm   #13
dseymo1
Dekatron
 
Join Date: Dec 2007
Location: Shropshire, UK.
Posts: 3,050
Default Re: Battery Boxes.

It's well worth considering the more recent 'pre-charged' NiMH cells such as the Eneloop already mentioned.
They really do what they say, having a very long charged shelf-life - ideal for an intermittently used radio. The discharge curve also helps prolong the effective life in most applications.
I use nothing else in my digital cameras these days.
dseymo1 is offline  
Old 30th Jun 2011, 8:08 pm   #14
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

I don't suppose anyone already sells a Reproduction B104 with AA rechargeables in it?

Where would I get the original style of plug & socket of a B104?
45V pack, no LT, 3.625" x 1.625" x 4.75" (or 92mm x 38mm x 121mm)
neon indicator is offline  
Old 30th Jun 2011, 8:21 pm   #15
ThePillenwerfer
Octode
 
ThePillenwerfer's Avatar
 
Join Date: Mar 2011
Location: Sheffield, South Yorkshire, UK.
Posts: 1,137
Default Re: Battery Boxes.

The obvious chap to ask is 'BatteryMaker' - the name says it all. I've made sockets by rolling tin 'round a drill bit and then glue-gunning it to a bit of formica.

- Joe
Attached Thumbnails
Click image for larger version

Name:	Battery Socket.jpg
Views:	273
Size:	58.3 KB
ID:	53254  
__________________
"Experts are only good at one thing: explaining why something will not work!"
ThePillenwerfer is online now  
Old 30th Jun 2011, 9:04 pm   #16
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

This may be of interest to people wanting battery info
http://highfields-arc.co.uk/beginner...teryequiv1.htm
Seems to cover all the common HT packs.

The original link from ThePillenwerfer (post #2) told me also what to look for so I found this too
http://mikeyancey.com/files/TransOce...b104layout.jpg
But it looks like the same file as on http://www.the-thompson-brown-family...eriesframe.htm (alias http://www.roberts-radios.co.uk/ )
neon indicator is offline  
Old 30th Jun 2011, 9:04 pm   #17
Dave Moll
Dekatron
 
Dave Moll's Avatar
 
Join Date: Feb 2005
Location: West Cumbria (CA13), UK
Posts: 3,728
Default Re: Battery Boxes.

Quote:
Originally Posted by ThePillenwerfer View Post
The obvious chap to ask is 'BatteryMaker'...
Forum name batterymaker1.
__________________
Mending is better than Ending (cf Brave New World by Aldous Huxley)

Last edited by Dave Moll; 30th Jun 2011 at 9:05 pm. Reason: quote added
Dave Moll is offline  
Old 30th Jun 2011, 9:05 pm   #18
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

Quote:
Originally Posted by ThePillenwerfer View Post
I've made sockets by rolling tin 'round a drill bit and then glue-gunning it to a bit of Formica.
Good idea

Though since I'm making it all, I need the plugs too. How would you do the plug?
Anyone know what the dimensions where/are on B104 plug/socket?
neon indicator is offline  
Old 30th Jun 2011, 9:31 pm   #19
neon indicator
No Longer a Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Battery Boxes.

Quote:
Originally Posted by Dave Moll View Post
Forum name batterymaker1.
Thanks,
I found some old threads but wherever he hosted all the pictures are gone.
He may also not be much in the mood just yet, I think I know how he must feel.
neon indicator is offline  
Old 1st Jul 2011, 2:02 pm   #20
broadgage
Octode
 
Join Date: Jan 2010
Location: North Somerset, UK.
Posts: 1,127
Default Re: Battery Boxes.

As regards paralelling nickel metal hydride cells, the suppliers advise against it.
There should be no need anyway with modern high capacity cells.
Nickel metal hydride D cells are available up to about 9 amp/hour, and F cells still greater. That should suffice for almost any set intended for zinc carbon dry cells. This high capacity cells are rather expensive, but that should not matter if only 1 or 2 are needed.

AA cells can be used in series for HT supplies, and I would regard a fuse as vital if useing rechargeable cells, and advisable even with alkaline cells.
Modern alkaline cells can supply 10 amps or more, which is a lot of heat in a small space if something goes wrong !
A 100ma fuse would be advisable for HT dry batteries.
For rechargeable HT batteries, a ceramic bodied fuse listed for mains voltage should be used, again 100ma should be fine.
broadgage is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 1:16 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Copyright ©2002 - 2018, Paul Stenning.