[ARC5] PS Hum in BC-453-B (solved!)

[Roy Morgan]

On Jan 24, 2015, at 9:15 PM, Bill Cromwell <wrcromwell at gmail.com> wrote:

> ... I'm operating my BC-453 from brom batteries on both the heater strings and the B+. I'm thinking the exposed, randomly strung wires from the batteries are picking up a small amount of hum from the nearby power lines and their wonderful field. … I will replace those wires with shielded cables ...

Note that Cat 5 computer data cable is especially constructed to reduce pickup from external fields.  I think it has 4 pairs of conductors and the shield.  You could run the filament current through two pairs and the B+ through a third pair.

Roy

 
Roy Morgan
RoyMorgan at alum.mit.edu
K1LKY Since 1958