[Johnson] Johnson 500 Power Supply?

[C E]

Hi Roger:
Since the unit has been butchered, the next best thing
to do would be to rebuild it in the best design
parameters possible. If there has been metal
modifications, start from scratch and rebuild
accordinginly. 

Best of luck to ya and Merry Xmas. Cal. 
--- Roger Shultz <nj2r at earthlink.net> wrote:

> A local OM recently bought a 500 with power supply
> missing the HV transformer. Well, the power supply
> is far worse off than just missing the HV
> transformer. From what I can see it only resembles
> the original supply in that it still has its
> handles! Hi!
> 
> The screen regulators have been removed, can
> electrolytics have been mounted in their place, the
> modulator seems to have been modified (disabled) to
> accept an external audio source probably from some
> sort of audio amplifier directly into the 811's and
> the 3rd audio and audio driver removed in the RF
> unit. The swinging choke in the power supply has
> been replaced with a non-swinging 5 HY model. The LV
> supply 10 HY choke has been replaced. The modulation
> transformer has been replaced as well. There are
> three undocumented pilot lamps on the chassis and a
> 0n-off toggle switch. The HV arrangement with the 3
> pin jacks is gone, Additionally there is an added
> relay for some purpose and numerous undocumented
> wiring changes. The chassis has lost much of its
> plating and is rusty to boot.
> 
> IMHO, this could be considered a basket case though
> it is probably an insult to baskets! 
> 
> At least the RF unit looks good from the outside and
> if the power supply could be salvaged, even at
> significant cost, it's a useful transmitter.
> 
> So, my questions for the list are:
> 
> 1. Were there different power supply versions?
> 2. Do any of these changes appear to resemble
> documented mods over the years?
> 3. What are the odds of obtaining a non-messed with
> power supply (do I hear screams of laughter?)? 
> 4. If possible at what cost?
> 
> It appears the only way to resurrect this thing is
> to carefully try and figure out the wiring and then
> proceed from there to put it as close to original as
> possible. Any thoughts guys?
> 
> And I thought KWS-1's were a pain in the neck!
> 
> 73, Roger, NJ2R
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