On Sun, 08 Apr 2012 07:02:43 +0100, Charles Ellson
wrote:

On Sat, 07 Apr 2012 21:54:51 -0700, spsffan
wrote:

On 4/7/2012 6:26 PM, wrote:
Two things to add:

One phone number in the 1964 PRR timetable as a "YL n-nnnn". The
phone company was experimenting was using two meaningless letters as
way to expand dialable codes; such as in Buffalo. This didn't catch
on, and they went to ANC instead.

Also, railroads and pipelines were two exempted businesses that Bell
would allow to own and maintain Bell telephone equipment due to the
difficulty of maintaining wayside equipment. The PRR owned a separate
long distance network, complete with toll testboards.

Some smaller railroads retained magneto local battery phones into the
1980s. They of course required periodic visits to replace the
batteries (No. 6 dry cells*), but the cells were designed for
intermittent use and lasted a long time (geez, today with alakaline
they could go many years).

*Do they still make No. 6 dry cells?


Big snip.

I think they do. I actually seem to recall seeing one recently
somewhere. Home Depot? Radio Shack ?

For those who don't recall, these are the large batteries about the size
of a 16 oz. beer can,

That sounds like an (IEC number) R40, a fairly universal cell with old
UK railway and Post Office telephone equipment.
Try :-
http://www.estarspower.com/products_battery_r40.html
The non-domestic versions in the UK usually had a wired negative
connection and were latterly used to power the radios in PO/BT vans
more often than in telephone equipment.

Ah, confirmation it is the same :-
http://www.smallbattery.company.org.uk/sbc_en6.htm
12 quid each :-(

IBM seem to have rather confusingly (and unwisely as it is an
international standard number) chosen the same number for one of their
laptop batteries.

with two thumb screw terminals on top. They were
common for use with kids science kits and I seem to recall that we had
them in the chemistry and physics lab in high school. (late 1970s)

Of course, God only knows what the insides are these days.

Still zinc-carbon, I would not like to see what happens if an alkaline
version was short-circuited.

P.S.
It seems someone does make an LR40 :-
http://cellpacksolutions.com/Search_...et.asp?ID=LR40
http://www.master-instruments.com.au.../LR40-EN6.html
but with a 48Ah capacity I'll leave the heavy current experiments to
someone else. ;-)

I think that
the brick shaped "lantern" batteries would serve the same purpose,
except that the No. 6 was 1.5 volts, like a common AA (or D or C or AAA
cell).