[Elecraft] KX3 power supply

[Jeffrey Otterson]

Hello Chip,

I did a lot of testing of KX3 power supplies, and the PAE is the quietest,
next to a linear power supply.

I had a fair amount of EMI problems, too, until I put a big ferrite bead
(Fair-Rite 0431176451) on the DC output wire.  I wound 6 turns though the
core, right at the power plug that goes into the KX3.  This brought the
noise down to barely audible, totally tolerable.

I bought the cores from Verical.com -- they had the best deal on them --
but they appear to be out of stock.  Mouser's got them for under $8.  These
are the same cores that K9YC recommends in his "RF Interference to Audio
Systems" paper.

73

Jeff n1kdo

---------- Forwarded message ----------
> From: Chip Stratton <lightdazzled at gmail.com>
> To:
> Cc: Elecraft Reflector <Elecraft at mailman.qth.net>
> Date: Mon, 18 Jan 2016 19:38:50 -0600
> Subject: Re: [Elecraft] KX3 power supply
> The PAE power supply works fine, but it still puts out enough hash that I
> can't use my loop antenna near it. It is better than others? Probably, but
> still not usable for me when near  the receiving antenna.
> Chip
> AE5KA