A 'stiff' HV is a very good thing for dynamic loads such as SSB. It starts
with the AC mains. Back in the 70s, I bought a new-to-me Heath SB220 that was
wired for 120V operation. It didn't take long for me to realize 240V was the
way to go... the HV had much better dynamic stability after the change. Take a
look at what the AC supply is doing under load. If it sags the same percentage
that the HV sags, there's your problem.
Fast-forward some 15 years and I noticed the HV on my SB220 began sagging under
load. New filter capacitors (replacing the 30 year old units) took care of the
problem. If providing 234V is easy, I recommend doing it. If your HV still
droops under load, take a look at the filter capacitor bank (dried-up
electrolytics are common on older amplifiers).
Ken Bessler wrote:
> I just picked up a NOS Yaesu FL-2100B. I used to own a
> TL-922A and for that I
> installed a dedicated 234v line in the shack. My 117v lines
> are a little crowded
> so I was thinking about converting the FL-2100B to 234v to
> use the line that the
> TL-922A used to use.
> When I key the new amp, the plate voltage drops from
> 2,350vdc to about 1,800vdc
> with the current 117v stock setup. I'm worried about
> the drop.
> So, should I convert the Yaesu to 234v operation? It would
> not be that hard for me
> skills wise and like I said, I *do* have the outlet......
> Ken KG0WX
> 73 de Ken KG0WX - Kadiddlehopper #11808,
> Flying Pigs #-1055, Grid EM17ip
Amps mailing list