[Heathkit] Heath HP-23 question

[Kim Herron]

Hi Ed and Rich,
>The only set for which I have intimate knowledge is the HW-18.  That set
>required 250 volt B+ or it would "burn up".......  that is, damage the
>final amp.
>On Wed, 27 Apr 2005 14:49:39 -0400 Richard Franzson <franzsrf at umdnj.edu>
>writes:
> > Also,  can someone please tell me why the newer HP 23 power supply
> > has an option for voltage levels. And the old version HP 23 did not.

       The HP-23 series supplies evolved over the years.  To begin with the 
supply was wired to deliver
250 or 300 VDC B+ depending where the switch on the supply was set and it 
also had a fixed and adjustable
bias supply and 6.3 or 12.6 VAC heater supply.  When the single band series 
of radios were dropped from the
line of gear, the supply options were also dropped.  The capabilities were 
still in the supply, but you had to hard
wire the supply to deliver what you wanted.  They also dropped the pot and 
voltage divider for the variable bias supply
and the supply eventually also was only configured to deliver 12.6 VAC for 
heaters.
         When Heath first came out with this supply is was not only 
designed to work with their SB/HW line of gear,
but for anybody who needed a supply to run any other transmitter, home brew 
or otherwise.  As that need declined
they changed what was available.  The extra parts they dropped saved cost 
and confusion later.


Thanks!!

Kim Herron  W8ZV
1-616-677-3706
Outgoing mail scanned for virus and worms
with McAfee Virus Scan