[Elecraft] voltage input dropping pwr out

[Ron D' Eau Claire]

> I can't seem to get the right amount of power out for each band, and my
> car battery will not give enough current for power out to be higher than
> 0.2W,  same for the power supply I have (which I might be able to fix)
> and my batteries.
>
> I only seemed to be able to get out 15.8W at 13.4V input.
>
> I am using a power cable that is used on CPUs.  How can I do better?
>
> Daniel


I'll assume that you are talking about a K2 and not a K1 since you mention
15 watts.

Unless your car battery is long past dead, it'll give you plenty of current.
The question is "what is the voltage at the K2?". With the K2 on,
momentarily press DISPLAY and note your voltage. It should be over 13 volts
in receive, and something over 12 volts on transmit at the full output of
the K2.

From what you say, I suspect that it is lower than that. So you get out your
voltmeter and check what you have at the cable side of the connector going
to the back of the K2. Note that it will be about 0.6 vdc or so more than
the K2 displays because of the drop in the reverse-protection diode in the
K2. If that's good, then your connector is making bad contact. It it's low
there go to the point where your power cable connects and check there and
keep working back to the battery. Somewhere you will see the voltage drop
under load disappear, and then you will know where the high-resistance
connection is.

Note that the K2 is RATED at 10 Watts output! SOME bands typically provide
more - something as high as 15 watts on some bands is not uncommon, but the
rated output of the K2 is 10 watts and that's just about all you will get on
some bands (typically 10 meters is the band where the output is lowest).

Also if you are using SSB, note that Elecraft recommends not going above 10
watts output on ANY band, regardless of who much output the K2 can make.
That's because the IMD suffers when the finals are driven above their design
specs.

Ron AC7AC
K2 # 1289