[Elecraft] Dead Battery

[Mike McCoy]

I have a nice lil Yaesu FP-4 linear (4 amp) PS that I use for my K2 (and
batt charging). Currently it puts out 13.2v (loaded) and I'd like to adjust
the voltage to 14v.

I don't have the schematic but it appears to be basically of a 'classic'
linear design. Thing is, it has TWO trim pots for adjustment. Long ago
(during my bench tech days) I remember tweeking such PS's to obtain the
proper voltages but I can't remember what the other pot is for (I think I
remember the 2nd is for adjusting the current limiting).

Prior to me just adjusting the first pot I come to (while measuring the
results) is anyone familiar with the FP-4 that can tell me specifically
which pot is the voltage adjust? and just FYI, what the other pot is used
for again?

Thanks & 73
Mike - AD5IU

----- Original Message -----
From: "Don Brown" <DolfinDon@msn.com>
To: "Jeff Burns" <jhburns@attglobal.net>; "Elecraft"
<elecraft@mailman.qth.net>
Sent: Monday, July 01, 2002 8:00 AM
Subject: Re: [Elecraft] Dead Battery


Hi

I don't see anything wrong with your setup. Maybe you just got a defective
battery. The battery should be able to charge at 13.8 volts indefinitely
with no damage.

The MFJ switching power supplies work very well I have 3 of them. The little
one without meters is only a fraction larger than a K1, weighs about 2.5
pounds and will drive a K2/100 at 20+ amps. It has an internal pot to adjust
the output up a little to 14 volts. Another advantage of using a larger
power supply is you can turn off the battery once it is fully charged and
keep it ready for field work.

Don Brown
KD5NDB