[RFI] Keyboard RFI

[Charlie Gallo]

On 8/22/2013 Jim Brown wrote:

> On 8/22/2013 10:03 AM, Charlie Gallo wrote:
>> One odd thing I found - every keyboard around the house (and I have different brands from cheap to Unicomp Model M keyboards) has horrid RFI_IF_  you are close to it (like the hand held within say 6-9 inches)

> Most trash like this is radiated as a common mode signal by the cable --
> in other words, the cable is a transmitting antenna.

Jim,
Forgot to point out that I did try choking the cable, no good.  In fact, for instance on this keyboard, cable comes out the RIGHT, signal highest on the left, Mid cable it is not measuring on the radio at all.  Remember I did say this is close distance only.  I might be to paranoid, but...

(and there is over $200 in type 31 ferrites on their way to me right now from Mouser)



-- 
73 de KG2V - Charles Gallo
Quality Custom Machine-shop work for the radio amateur (sm)