On Sat, Dec 11, 2004 at 08:26:20AM +1300, Ron W wrote:
> Hi Elecrafters,
> Does any one have any info on the MFJ miniature psu type 4103? Although it
> is a sealed unit I wish to adjust the output to keep my internal battery
> charged. The nominal output voltage is 13.8 and I wish to adjust to give
> 14.2 as measured by the K2. I think the unit could be carefully cut open
> and after adjustment sealed up again. Before starting on this exercise I
> thought I would check with your collective wisdom.
> 73
> Max/ZL4vv
I have one and it is a nice unit (no noise problems), but the output is
not really high enough to charge the KBT-2. I measure 13.3 volts on the
K2's internal display, while the KBT2 manual says the acceptable range
is 13.6-14.0 volts. On a partially-discharged battery and after several
days it brought the voltage from 11.1 to 12.4 volts, as measured on the
K2's internal meter, which indicates that it partially charges the
battery (I normally use a small linear supply, adjusted to 14.2 volts,
which fully charges the battery).
The 4103 is small and lightweight and suitable for travelling. I took
it and my K2 to France earlier this year and when I unpacked, discovered
that I had forgotten the power cord. Fortunately, the 4103 uses the
same cord as desktop PCs, which is easily attainable practically
anywhere. No switching is required when going between 120 and 240 volt
mains systems.
Unfortunately, it doesn't come with a schematic, so I don't know what is
involved in modifying the unit for a higher voltage. If you are
successful in raising the output voltage of the supply, please let the
list know.
73, Bob N7XY
_______________________________________________
Elecraft mailing list
Post to:
[hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help:
http://mailman.qth.net/subscribers.htmElecraft web page:
http://www.elecraft.com
Locked
