Power supply conections / control

[Stu Lyon]

I recently acquired a K2/100 and a KAT100-1 and I am unsure
about the preferred method of applying power the KAT100. The
KAT100 manual implies that the power should be applied
before or at the same time as the K2 (which I assume is for
communication issues). Does that mean a separate dedicated
line to the 14V power supply?

A method I'm considering is to add a jumper inside the K2
from the cathode of D12 to the anode of D12. This would
place the switched 14V out the 2.1mm power plug. A short
2.1mm-to-2.1mm cable would then connect to the KAT100. The
K2 and KAT100 would be powered up simultaneously. The
downside would be the additional current drawn through the
K2 power switch.

Another possibility would just to short out D10 (and the
jumper cable installed) so that whenever the KPA100 is
powered up so too is the KAT100. Which may not be a bad
thing This still requires a mod to the K2.

Is there a better way?

73, Stu W6CUX


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[Don Wilhelm-3]

Stu,

The better (and to my mind simplest) way is to run a dedicated cable from
the power supply to the KAT100, and also run a cable from the power supply
to the KPA100.  If you prefer to switch the power supply off when not
operating, the procedure is to turn on the power supply first and then press
the power switch on the K2 - everything will work 'as advertized'.  If you
do not switch off the power supply, then the only thing you need to do is
press the power switch on the K2 and all will be well.  The KPA100 and
KAT100 are powered on and off under control of the K2 power switch, and very
little current is drawn from the power supply with the K2 powered off.  The
KPA100 does draw a small amount of current with the K2 off, but the power
drawn by the KPA100 when the connected K2 is powered off is extremely small.
Unless you are running from a vehicle battery where a few milliamps of draw
when the K2 power switch is off would cause a problem, it should not be of
any concern.

73,
Don W3FPR

> -----Original Message-----
>
> I recently acquired a K2/100 and a KAT100-1 and I am unsure
> about the preferred method of applying power the KAT100. The
> KAT100 manual implies that the power should be applied
> before or at the same time as the K2 (which I assume is for
> communication issues). Does that mean a separate dedicated
> line to the 14V power supply?
>
> A method I'm considering is to add a jumper inside the K2
> from the cathode of D12 to the anode of D12. This would
> place the switched 14V out the 2.1mm power plug. A short
> 2.1mm-to-2.1mm cable would then connect to the KAT100. The
> K2 and KAT100 would be powered up simultaneously. The
> downside would be the additional current drawn through the
> K2 power switch.
>
> Another possibility would just to short out D10 (and the
> jumper cable installed) so that whenever the KPA100 is
> powered up so too is the KAT100. Which may not be a bad
> thing This still requires a mod to the K2.
>
> Is there a better way?
>
> 73, Stu W6CUX
>
>
> _______________________________________________
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>
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