[TenTec] OT: Question about TS-590 possible problem

[Rick - DJ0IP / NJ0IP]

A couple of my friends are preparing for an expedition for CQWW and are testing their config.
They have 2x TS-590 transceivers and a pair of yagi antennas in close proximity of each other (about 75' apart).

The problem, they are seeing a broadband noise as soon as they key one of the transceivers.
Even with just 5w of power it is wiping out the other rig on all bands.

My old grey cells seem to remember we discussed this here on the Ten-Tec reflector about 6 months ago or so.
Does anyone remember the details of this or do I have my wires totally crossed?
Was there a fix or have I dreamt this up?

TNX guys, and sorry to spam the group, but if we can get these guys fixed, we'll have a nice multiplier in CQWW.

73
Rick, DJ0IP