[Collins] Bucking transformer for 30S-1 finished!

[frank hughes]

Hi,

I have been thinking about how to reduce the line voltage for the 30S-1 for
some time.
Variac is the easy way, but for the amps capacity on 240, all the units I
have found were too large for my tiny shack space.

The recent article about "bucking transformers" in ER caused me to look
over the piles'o transformers at the
local electronics surplus place for a candidate.

AC line here runs 253 VAC at low-load times, and drops a little during high
load periods.
The 30S-1 manual says "230VAC input", so I tried for that value.

The transformer I found is a Center Tap, so I wired the input for 240.
The transformer has two 50A 6VAC secondaries, and two 25A 12VAC
secondaries.

I tried the 12vac first, but it dropped the line below 220vac, which I
thought too low for the 30S-1.
The 6vac secondaries were just right, very close to 230vac output.

I bolted the transformer to the ceiling, out of the way of everything else.

Unfortunately, the surplus place did not have another identical transformer
for me to use with the 30L-1,
but that just gives me a good excuse to return on a regular basis and snoop
around for my next project!

73
Frank
KJ4OLL

http://s180.photobucket.com/albums/x257/fish1_07/transformers/