"CP" wrote in message
. ..
Thanks but I found these too with the usual searches.
Bob

First Heathkit receiver that I built in 1972

Restoration (Electric Radio -- Nov 2006)
http://www.willydog5.com/index.php?o...13&Itemi d=39

http://listserv.tempe.gov/admin/WA.E...th&F=P&P=18331

I have paper copies (notes and some copies) of the HR-10B modifications
that you are asking about -- but have not found an Internet source.
Many of these are marginal to bad.
The voltage regulator tube mod for regulation of the VFO voltage
is probably the most popular.

gb