19 Set Control Unit Batteries

[James D Teel II]

I’m in the process of restoring the control unit for my 19 set. Are the batteries pictured 1.5v, and if so, can anyone direct me to where I can find proper period looking replacements?

[Chris Suslowicz]

Hi James,

Yes, they are "Cells, Dry, X, Mk.II" originally, those are the post-WW2 cardboard cased version (one variety, anyway), Battery, Dry, 1.1/2 Volt, No.12
(WB 0200, NBA 300 or 6135-99-910-1135). The modern contents are a 1.5 volt size 'F' dry cell (original cells were actually square section and wrapped in tarred paper, modern ones are circular cells in cardboard cases and wax-dipped.)

I don't believe there is any modern production of this unit. (What we need is someone with a 3D printer to mass-produce a casing that will take a 'C' cell in a holder that can be "dressed up" as a WW2-style item.)

Best regards,
Chris.

[charlie fitton]

What is the input voltage range that the radio can handle?


Might be worth it to mock up a top, and replace the innards with a Lithium-whatever battery pack and have power forever..

[rob love]

I picked up a pair of those remote control units form the local surplus store back around 1979. I was in the militia then, and the old signals Sergent went into the back room and brought out some reasonably fresh batteries for the units. I'm not sure what else they were used in back then, but they were still in use with some piece of equipment or another.

Come to think about it, I have a portable desklamp hiding somewhere which also uses those same batteries if I recall correctly. I saw those go surplus in the 1980s, so likely the batteries were still around for use in those.

[Chris Suslowicz]

Originally Posted by rob love

I picked up a pair of those remote control units form the local surplus store back around 1979. I was in the militia then, and the old signals Sergent went into the back room and brought out some reasonably fresh batteries for the units. I'm not sure what else they were used in back then, but they were still in use with some piece of equipment or another.

Come to think about it, I have a portable desklamp hiding somewhere which also uses those same batteries if I recall correctly. I saw those go surplus in the 1980s, so likely the batteries were still around for use in those.

They go back at least to the first world war, when they were used in Telephone Set 'D' Mark II (and later models), Fullerphones, the Daylight Signalling Lamp, and other things that needed a small battery supply.

Switchboard U.C. (6-line or 10-line) uses three of them, the 10-line Magneto Switchboard (W.D.) used a pair for the "night alarm" (plus another pair in the operator's Telephone Set 'J').

It's possible that they're not completely obsolete yet, though adapters were made to fit a pair of 'D' cells in Telephone Sets J & L by the manufacturer, and modern field telephones tend to use C or D cells.

Chris.

[David Dunlop]

To follow through with Rob’s comments a bit, I have a pair of these dated 04/77 and 02/78 made by Union Carbide in Toronto. Plain beige cardboard with black printing, identified as “CF BATTERY BA-300/U”. I have never seen any dated beyond the 1980’s.

Wartime production batteries I used to have were made by WILLARD BATTERY. Identical in construction but in olive green waxed cardboard with black trim and printing. A very ornate design compared to the bare bones look of the postwar product.

The brass terminal assemblies are still available and beige Manila cardboard is very close to the look of the postwar product. It would not be difficult to dummy working D Cell driven replicas.

David

[Chris Suslowicz]

Originally Posted by charlie fitton

What is the input voltage range that the radio can handle?


Might be worth it to mock up a top, and replace the innards with a Lithium-whatever battery pack and have power forever..

It doesn't really apply in this case. The battery is 4 cells, giving 6 volts tapped at 3 for the carbon microphone (it's basically a field telephone with added bells and whistles (well, in this case a keying relay and some extra switchery)).

The 6 volts is used to operate the keying relay at the 'local' (to the set) end, and extra cells can be added if the line circuit has too much resistance for it to operate reliably.

Chris.

[charlie fitton]

Originally Posted by Chris Suslowicz

It doesn't really apply in this case. The battery is 4 cells, giving 6 volts tapped at 3 for the carbon microphone (it's basically a field telephone with added bells and whistles (well, in this case a keying relay and some extra switchery)).

The 6 volts is used to operate the keying relay at the 'local' (to the set) end, and extra cells can be added if the line circuit has too much resistance for it to operate reliably.

Chris.

Nom voltage for a LION battery is 3.6v per cell, if the circuits can handle that, then your radio will run for months between charges. Keep the rare batteries for show.