On Sun, 8 Feb 2009 00:39:55 +0000 (UTC), David Lesher
wrote:

Bruce L. Bergman writes:


Lorain built lots of gear for telephone switchrooms, and they run
-48V DC native. With two Military Jeeps as the power source, he could
have brought one of the pre-made (not custom) CO Power inverters.

Lorain made LOTS of stuff. I don't recall CO 60 Hz inverters but midst
many other products, they could have been there. In any case, Phil
didn't know the Stupids would "borrow" his borrowed unit.

C.P. Stocker's first product was the Sub-Cycle; a ferro-resonant tank
that was tuned for 20 Hz out, but kicked by 60Hz. SubCycles supplied
ringing voltage for hundreds of Central Offices.

It replaced ugly motor-generators [big CO's] and the vibrating reed
disasters that DoN mentioned; they were used in small CO's including the
runts: Community Dial Offices.

Later SubCycles came with 30 Hz output, widely used in PBX's; they were
far cheaper to make.

Unlike MG's and reeds, SubCycles were zero maintenance & ran untouched
for decades. They were overvoltage/short circuit proof. [Worst case,
they'd deliver their rated output into a short..]

Later Lorain made loop extenders [basically upped the loop current on
long rural lines by increasing the voltage], loop amps [gain for long
loops], big, no BIG battery chargers of many sizes, [Lee had a surplus
~800A/9vdc unit; most were for 48v strings, with equalization.] and
inverters up to the low fractional-megawatt range.

I did mention I was in COE Construction at GTE for several years
right at the tail end of Step and the dawn of Digital, right? I've
messed with most flavors of what you just described - and the End Cell
rectifiers were usually 6V and not that big, in the 200A range, one
per office. They only had to bring the end cells back up after a long
outage, and the float and equalize.

Didn't get down to the component level repairs much, but lots of
putting in and taking out. And some of the gear dated to the 1930's
like the Western Electric N Carrier that was still in operation into
the 1970's, and the Audichron time and temp drum announcer at San
Fernando. Rube Goldberg would have been proud.

-- Bruce --