I just looked at the 95 Handbook and was disappointed to see several
mistakes in the HV power supply section.
One of the most glaring is they fail to discuss ESR, even though they
show it as a resistor in the chart used to calculate voltage sag and
capacitor size!
They also, quite incorrectly, describe how to estimate transformer
current rating by looking for a 10% secondary voltage drop. Obviously
that method means nothing. It not only fails to check the current rating
of the wire inside, it makes no allowance for core or winding HEATING!
If anyone else has found errors in that section please E-mail me, I want
to forward a list to the ARRL. It's important that our main amateur
reference book be as accurate as it can be. I'll compile the list and
post it here.
Please include all power supply errors, even those like the error in the
3-500Z amplifier where one primary leg of the filament transformer is
grounded to the chassis!!! That is a violation of electrical codes and a
safety hazzard, since an open mains ground can cause the chassis of the
amplifier to reach line voltage and kill the operator!
73, Tom
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