[Elecraft] Digout1?

[Cady, Fred]

Hi Jim,
The schematic I have doesn't show the pin 11 inhibit pulled low in the KAT500. It goes to the microcontroller through a series 4.99K resistor.
But what it is used for in the KAT500 is an interesting question.

Back to your original question, I have the K3-KAT-KPA set up and use Digout1 to switch the PR6. I'd have to check more closely but I don't think the KPA or KAT is pulling pin-11 low all the time.

Cheers,
Fred


Fred Cady
fcady at ieee dot org

> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net [mailto:elecraft-
> bounces at mailman.qth.net] On Behalf Of Jim Miller
> Sent: Friday, August 09, 2013 6:18 PM
> To: Elecraft Reflector
> Subject: Re: [Elecraft] Digout1?
>
> 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
> >
> >
> >
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