"Ron Wanttaja" wrote in message
...

The trouble is, to shield everything, I need to completely wrap around the
back end of the radio. It's 3.375" per side, so I'd need copper tape
about
16" wide, and about the same dimension long to have some overlap on the
back of the radio and still go along the wiring harness a bit."
McMaster-Carr's got copper tape 50 feet wide, but it's only 3" long. :-)


OTOH, 6 - 16" long pieces of tape overlapped 1/4" results in a sticky sheet
about 16" square.

I'd start by spiral wrapping the harness, making sure to contact the
overbraid on the one end and end with solid contact around the connector at
the back of the unit.

If the unit is metal, you shouldn't need to shield the unit itself with only
a couple exceptions. Since we're dealing with a transponder (1090 MHz), the
only other issue would be an aperture which could act as a slot antenna. If
there are cover edges that don't have good metal-to-metal contact or other
openings, put a strip of tape along the gap. (Note that a gap running the
length of one side (3.375") would be just shy of 1/4 wave at 1090 MHz.)

I've sealed up much larger air transport units (big ARINC boxes) with a
couple feet of 1/2" tape.

Gerry