[R-390] Isolation Transformer update

[Scott, Barry (Clyde B)]

I did some experimentation last night.  With no load and the primaries
connected in parallel at the 120V tap, the primary drew about 350mA.  At the
110V tap, it drew almost 500mA.

I then connected the series 75W light bulb.  The 120V tap caused a dull glow
while the 110V tap produced about twice that brightness (although still
quite dull).

I didn't attempt the primary at the 104V tap.  I did notice the transformer
produced a bit more hum at full voltage when at the 110V tap than at the
120V tap.  I did not notice any heating, but I didn't leave it on very long
either.

Do these results sound typical?  I've never examined the primary current
draw on a transformer at no load.

Thanks,

Barry(III) - N4BUQ