On 2021-07-08 11:47, Max via groups.io wrote:
Sounds like rf maybe coming in through the mike cable. The bigger
problem is the fact that none of the jacks (mic, keyer, antenna, etc.)
are grounded to the case BEFORE entering the radio. AS is, I'm not
sure if the case does much shielding at all. Sorry to say it, but this
part is a bad design!
** I disagree. Vehemently. Connectors should NOT be individually grounded
to the case. The case should be grounded to the ground plane in one spot,
and one spot only.
If you ground the case in multiple places, you risk causing RF currents
to flow through it. This can cause the case to act as an antenna, rather than
as a shield. For low level audio, it can cause "ground loops". Same deal.
- Jerry KF6VB
