Topband: For K3 users

[Guy Olinger K2AV]

Remembering what it was like to replace Pro III's and MP's with K3's, I
found the differences to be breathtaking. But specific problems with very
close BC stations can be for a range of reasons, of which some have nothing
to do with the radio. Depending on exactly what is going on the results
might be a large improvement or no improvement at all.

Listening to a very large quad on Europe, my MP had a low level of noise
that I always thought was the ambient noise floor. The K3 showed that the
prior noise floor was really the MP's receiver.  The K3 was able to hear a
new layer of weak Russian stations never heard before. The K3 was also
remarkably better at rejecting close very loud CW signals (as in up or down
400 Hz), using the 8 pole CW filters. It even has noise blanker settings
that significantly help with key clicks.

The front end of the K3 has band pass filters for the ham bands. They are
deep enough that if I want to listen to the Yankees baseball games on 880
kHz, I need the add-on filter that passes the non-ham frequencies. The
preamp of the K3 is mild, only about 10 dB, so the low levels of some RX
antennas will still need a stand-alone preamp that still may need a
passband filter in front.

It is also possible that if your city noise is loud enough, the noise level
will cover up any real difference between a Pro III and a K3.

Your best bet is to arrange with someone who owns a K3 to bring it to your
location, and see the difference side-by-side with your Pro III. Then
you'll know whether the K3 helps you in your situation.

73, Guy.


On Sat, Oct 5, 2013 at 11:44 AM, Jose Orellana - EA7BJ <ea7bj at hotmail.com>wrote:

> Hi all.
> I currently live in a city of average size but quite industrialized.
> Also very close, about 1km (3 miles), a AM broadcast station 882khz with
> 10kw.
> My currently  rig is an IC-756PRO3, and noise in 80 and 160m is 9/9 +10.
> To RX, I use a loop (kc2tx) plus a preamplifier (w7iuv) and a bandpass
> filter.
> I'm thinking of changing my actual rig and acquire one that is more immune
> to city noise and intermodulation  of BCB.
> My first choice is a K3, but first I would like to ask a question ...
> Will I get to improve my reception (on low bands) with this rig ?
> 73, EA7BJ, Jose.
> _________________
> Topband Reflector
>