[RFI] DigiKeyer II

[Peter Laws]

On Thu, Jan 2, 2014 at 3:31 PM, Dale J. <dj2001x at comcast.net> wrote:
> Hi Peter, de Dale, K9VUJ
>
> If you got a computer connected the most likely place at least that I've found is the keyboard cable and mouse cable picking up RF and distributing it all over connected devices.  I myself have my mouse and keyboard cables wrapped in #31 mix snap-in's.  Be sure the snap-on is making good contact at it's mating surfaces.  Wrap tightly with tape if the snaps do not seem to close it properly.

To review: same setup with a Rig Blaster Plus in place of the DK-II,
including a connection to ACC1 on the IC746Pro never had this issue;
If I disconnect the DIN connector at ACC1, the problem vanishes - this
is not true if I disconnect the Key or CI-V lines (all of which come
from a DB15 on the unit, as you surely know).

> The two mating surfaces have to come together completely, otherwise it's as if it were't even there.  The best of course is a solid ring, but with keyboard and mouse cables it's not alway easy to get the USB connectors though the ring several times unless you buy a big one, a little more $.

I bought a bunch of #31 and #43 Fair-rite 2.5" toroids and yes, they
are "expensive" but not compared to the DK-II!  Four turns of the
interface cable through a #31 toroid changed nothing.

And yes about the snap-ons!  A few years ago, while fixing a different
RFI issue, I heard no change in the noise as I put the choke over the
wire until the two halves mated - boom! gone.  I touched/untouched
several time just to convince myself I wasn't imagining things, so
yeah, ferrite works and it has to be all the way around the cable!



>
> I've had zero RFI problems with my digikeyer.  They are pretty RFI proof, so I don't understand why you are having such a time with it.  That is the nature of RFI I guess, it's all black magic…hi, not really, but frustrating at times.

On that we can all agree:  it's magic.  :-D



-- 
Peter Laws | N5UWY | plaws plaws net | Travel by Train!