<nuckolls.bob@cox.net>
At 10:55 PM 8/31/2008 -0400, you wrote:
<jimw_btg@earthlink.net>
>
>I had a conversation with an engineer from the mfg of the Buck Puck and
>the very first thing he suggested is to package the PWS in a
>container. Just going to try this? Hope he is right.
That's half the battle. Containers provide (1) attenuation
of radiated emissions and (2) ground reference for line filters
to attenuate conducted emissions.
A metallic enclosure MAY be necessary. Line filters are
the first thing to try. That's why I asked if the noise
conduction path had been identified in an earlier post. If
the noises are noted coming in through the antenna on
vor/com receivers, then the filters need tailoring for vhf
frequencies . . . MUCH smaller/easier than audio/LF
frequencies that plague other victims by conducting noise
out on power lines.
One observes by the packaging of the Buck Puck that it was
not designed to be a stand-alone product but a component
of a more comprehensive assembly. The elegant solution
for integrating this device into airplanes is to built
an adapter board that also mounts a d-sub connector.
The line filter components can be assembled on the board
along with the connector and power supply.
Once the filter components are wired in, you can test to
see if the noise went away. If not, mount the assembly in
a metal enclosure where the 'ground' side of the filters
are connected to that enclosure.
I'll lay out a board and get some WAG filter components
ordered. I need to know if there is continuity between
the LED- and Vin(-). If you can get me this bit of
info, I'll finish the board layout and get those ordered
too. Also, do you plan to use the CONTROL or REFERENCE
features of these devices?
If you are going to build a board, it would be good to keep all options
open.
Roger
Bob . . .