[HBR] Power Supplies used in HBR 14 and HBR 16

[Don]

I hope everone has a pleasant 2007 holiday season. 

A death in the family this year kept me off the workbench. However, I am
ready to tackle another project. 

I have a question concerning the HBR power supplies and how the choke
and transformer requirements were determined. I believe I generally know
the answer but would appreciate a clear reason for doing what I have
done in the past....overkill. 

My question: The sum of the plate and gride currents for the tubes used
in the HBR 16 exceeds the currents listed in the tubes specs. The tube
specs show the sum of the typical plate currents alone to be approx
157ma. The HBR 16 only uses 150 ma choke(s). The transformer requirement
in the HBR 16 is for 120ma.

How do you scientifically choose the ratings for the transformer and
choke assuming the recommended plate voltage is used?

After the fact I can measure but what rule of thumb would help up front?


There was a mention of HBR receivers in January 2008 QST. 

Don K5UOS