[arm-allstar] Noise from BBB

[David McGough]

Hi Robert,

Recent Wal-warts can be awful, awful, awful noise sources! I've even got a
some 19V laptop power supplies that wipe out HF---S9+20 broadband noise
on 75meters. The noise is coupled to the house wiring via the AC source. 
The noise is everywhere!

As I've mentioned in other messages, I -highly- recommend these cheap
DC-DC step-down switchers. I'm now using them 100% for BBB, RPi2 and
Odroid C1 power supplies, with outstanding results. See:

>From China (these have taken about 2 weeks shipping for me):
http://www.ebay.com/itm/251564887056

Previously, I've also purchased "the same" power modules from the US ebay 
seller: NYPLATFORM  ...But, they seem out-of-stock right now. This seller 
had about 2 day shipping.

Note that I'm using wal-warts to power these DC-DC switchers, too, in
several setups.  However, I'm using "old style" (read that as: QUIET!),
unregulated, transformer 9VDC to 15VDC 1A supplies. These warts are
nothing fancy: a step-down transformer, full-wave bridge rectifier, and
output filter capacitor....But, they're QUIET (and they're cheap!).

73, David KB4FXC





On Thu, 30 Apr 2015, Robert Newberry wrote:

> So my home node of 6m gets kerchunked.  I have this constant level of
> noise. This is observed as I park in my driveway and the noise gets picked
> up next to me house. I went to the basement and flipped breakers. My ham
> shack was the culprits. One source is an old micronta 12 power supply. Ok
> so I unplugged that. The second Source is my BBB. I pulled the barrel plug
> and thr noise goes away. So my guess is if it was the walwart it would of
> kept up since I killed the power to the BBB. I also removed the plug for
> the USB URI.
> 
> Has anyone experienced noise from their BBB?
> 
> N1XBM
> Apparare Scientor
> Paratus Communicare
> Allstar Node # 27086, 41540, 41812
>