[Elecraft] Digout1?

[Jim Miller]

I found a thread on this reflector that mentions the PIN11 problem. It was
from April of this year and I had forgotten it. I'll just break another pin
off in the Key Line Interrupter to solve the problem.

Another mystery however is why the INHIBIT line is there in the first
place. Its operation isn't described in the KAT500 and the KAT500 has it
permanently pulled low. Note that the KAT500 document calls it INHIBIT
(inferring a positive active polarity) while the KPA500 document calls it
INHIBIT# (inferring active low polarity.) Since I have the INHIBIT IN
disabled via the KPA500 menu nothing is happening here anyway between them.

In neither document is the purpose described. Note that this is not the PTT
(PIN10) which is well documented and working fine for me.

Still not clear either why the KAT500 would have this line pulled low.
According to the KAT500 schematics PIN11 is passed through and only sensed
by the microcontroller via a 4.99K/0.1uf network. The cable when
disconnected from the KAT500 but still connected to the K3/PR6 doesn't
interfere with the DIGOUT1 function. Only when the KAT500 is connected.
BTW, for this test the cable going to the KPA500 is not present so neither
the cable or the KPA500 can be contributing.

Looks like it's time to open the KAT500F.

jim




On Fri, Aug 9, 2013 at 3:32 PM, Jim Miller <jim at jtmiller.com> wrote:

> I've got the K3/KAT500/KPA500 all chained together with the Elecraft DB15
> accessory cables.
>
> I'm now in the process of connecting up the PR6/DIGOUT1 enabling line.
>
> I've removed the jumper in the PR6 and connected the control signal to the
> PR6 to DIGOUT1 and all works well; switching the CONFIG: DIGOUT1 menu entry
> causes the relays in the PR6 to switch audibly.
>
> However when I connect up the DB15 chain to the KAT500 the DIGOUT1 line is
> permanently pulled low.
>
> Referring to the cable diagram and the KAT500/KPA500 connector callouts it
> appears the KAT500/KPA500 use the same PIN11 as DIGOUT1 for an INHIBIT#
> function.
>
> I disconnected the KPA500 from the chain and the KAT500 appears to be
> pulling this line low all the time.
>
> Do I need to remove PIN11 from the cable as well? I already have the
> Keyline interrupter installed which has PIN10 removed.
>
> Confused...
>
> jim ab3cv
>
>
>