Re: power to remote KPA100/KAT100 question

[Geert Jan de Groot-3]

> I would like to have one power cord with a  "Y" connection to the KPA100 -
> and have the KAT100 get it's power internally in the EC2 from the KPA/100. I
> would like to be able to have all three modules (the K2, the KPA100, and
> KAT100) turn on via the front on/off switch on the K2.

Note that the KAT100 has an internal power connector, as well as
the small, round connector on the back like the K2 has.
This gives possibilities for people with KAT100/KPA100-in-one-box
like myself.

I changed the KAT100 a bit so that:
- Power to the whole setup enters via the KPA100, via the powerpole plugs
- The KAT100 is powered through the internal connection between the
  KPA100 and the KAT100
- The KAT100 is modified so it _gives_ output power via it's small
  round plug on the back. I put a diode in for safety (as well as
  a fuse).
- The K2 is powered from this KAT100 plug using a simple jumper cable
  connecting the round connectors of the K2 and the KPA100/KAT100 box.

So, to connect the two boxes holding the three units, I only have
4 cables:
- From the powersupply to the PowerPole connectors on the KPA100
- Three jumper cables (power, RF, AUXbux) between the K2 and the
  KPA100/KAT100.
... and that is all.

Note that the KAT100 and KPA100 are always powered this way, but
shut themselves down if the K2 is off. This is how the design
is intended, and 'off' still means 'off'.

The good news is that the power sequencing requirements are met
so that the whole setup powers up correctly.
Also, current requirements on the K2 itself are low enough that
this just works, and works well. It also minimizes on ground loops.

Just a thought,

Geert Jan
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[Mike Harris-9]

G'day,

All I do is common the individual power leads to the K2 and external
KPA/KAT at the power supply.  Seems the simplest thing to do and ensures
the correct power up sequence.  No diodes required, no voltage drop on the
KPA lead passed through to K2.  Things can be made too complicated, KISS
rules.

Regards,

Mike VP8NO

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