[Elecraft] KPA-500 vs others

[Jim Brown]

On 6/22/2011 8:37 AM, Ron D'Eau Claire wrote:
> I think it would be great if we had at least one MF Ham band with a maximum
> power of 10 or 20 watts.

While I certainly enjoy QRP, it should be be remembered that one of the 
greatest problems facing ham radio is the increasingly high noise level 
from all sorts of switching power supplies, plasma TVs, motor 
controllers, solar power systems, and power line arcing. I live out in 
the country, with my nearest neighbors nearly a block away. Although my 
noise level is sometimes as low as S1 (on my calibrated K3), it can 
increase by 20dB or more when someone fires up one of those noise 
sources. On 6M for example, one neighbor (at about 120 degrees), has a 
solar installation that brings that noise level up to about S5 during 
the day; another, at about 60 degrees, has a switching power supply with 
a 75 kHz wide, S5 hump of noise that drifts up and down between about 
50.05 MHz and 50.2 MHz. When either of those sources is active, it means 
that the station on the other end needs 24 dB more power to work me than 
if the noise were not present. 24dB is roughly 250 X the power. At least 
half of my 6M QSOs this summer would not have been possible if those 
noise sources had been present -- I would never have heard the other 
station. Most hams have far higher noise levels than I do.

The greatest justification for running more power and putting up bigger 
and better antennas is RF NOISE experienced by the ham on the other end.

73, Jim K9YC