Bo-Lennart wrote:
Hi all out there.
I found a transformer in my basement. I don't know if its a
audio-output transformer or just a power transformer. On top it's
stamped "GALVIN MANUFACTURING CORPORATION",
and a model #: "25B31296-E" and a serial# ( ???? ) "138226"
At bottom there is 8 solder lugs, stamped: "1 to 8".
And at one side is 8 screw connector, labeled as "3A 12 11 2B 2A 10
1A 9".

To me it looks more like a tube output transformator, more than a
power transformer.
It seems to be from the 1940 or somewhere around there.

Anyone know what it is, and have some kind of "schematic" of the
transformer.

Many thanks in advance

Bo-Lennart Karlsson
Falun, SWEDEN

Galvin Manufacturing was the original radio manufacturing company that
eventually became Motorola. They started making consumer radios, and then
invented a record player that could be installed in an automobile. Thus,
came the name MOTOROLA, from MOTOR cars, and the old victROLA record player
(from RCA).
The 25B31296 part number identifies as a Motorola transformer, having the
following characteristics from the US military stock system:

5950-00-648-0404 Features
MRC Parameter Characteristics
ABKQ Center to Center Distance Between Mounting Facilities Parallel to
Length 2.625 inches nominal single mounting facility single center group
ABKR Center to Center Distance Between Mounting Facilities Parallel to
Width 2.375 inches nominal single mounting facility single center group
ABTB Mounting Hole Diameter 0.125 inches nominal single group
ACZB Frequency Rating 60.0 hertz nominal single component
ACZC Input-Output Phase Relationship Three phase to three phase single
component
ADAQ Body Length 3.875 inches nominal
ADAT Body Width 3.875 inches nominal
ADAU Body Height 3.500 inches nominal
AKNA Inclosure Type Hermetically sealed
AKPV Mounting Facility Quantity 4 single group
AXGY Mounting Method Flange single group and unthreaded hole single
group
BPLC Winding Function and Quantity 1 primary single component and 2
secondary single component
CWJS Winding Operating Voltage 145.00 ac volts nominal single
component 1ST secondary
CWJS Winding Operating Voltage 12.00 ac volts nominal single component
single primary
CWJS Winding Operating Voltage 5.80 ac volts nominal single component
2ND secondary
TTQY Terminal Type and Quantity 8 threaded stud and 7 tab, solder lug


No indication of the equipment it was used in, but more than likely a piece
of military equipment. Since the primary is specified as 12VAC, and
secondaries as 145V and 5.8V, it is likely to be a power transformer from a
vibrator power supply used in a military radio of some sort. Don't know how
the 3-phase spec works into it... could just be how the vibrator side of the
transformer was described.

Cheers,
Dave M