[TenTec] 961 on the left side of rig

[Dr. Gerald N. Johnson]

On Wed, 2009-11-25 at 09:35 -0500, David & Chris Drake wrote:
> Hi,
> Anyone know of a shielding workaround to place a 961 power supply on the left side of the rig?  IE: eliminate hum on the audio.
> 
I presume the problem is one of the magnetic field from the power
transformer injecting hum into some audio transformer or inductor in the
radio. A magnetic shield should help. Either over the sensitive part in
the radio or surrounding the entire power supply. Steel is a fairly good
magnetic shield, and is available. A steel box should do, one that holds
the entire supply. Mu metal would be better accomplishing the shielding
with thinner and thus lighter metal, but is much harder to acquire and
pay for. Experiment with a piece of sheet steel (1/16" thick is better
than something thinner) the size of the left end of the radio between
the power supply and the radio. It won't be as complete a shield but may
be adequately effective.

> Using a well shielded heil mic into a 715 processor, and a TT supplied cable to rig.
> Thanks,
> David
> Wd9cmd

73, Jerry, K0CQ