[AMRadio] 40M

D. Chester k4kyv at charter.net
Mon Sep 21 11:45:44 EDT 2009

To a  certain extent, the same thing has happened on 40m since (most of) the 
BC stations  went away, as happened on 75 when the band was expanded down to 
3600.  Back in the spring, there was a lot of activity on 7160 at first, 
until the novelty wore off, and gradually the activity has dwindled.

Then, there is the summertime QRN, combined with Daylight Shifting Time.  In 
the summer months, many of us are engaging in outdoor activities until 
sundown, and by the time we come in the house, grab a bite to eat, and then 
try to play radio, we find that many of the hams on the air are already 
signing out to play the go to bed early/get up early routine for the next 
work day.  And the remaining signals are often difficult to copy through all 
the atmospheric noise.

Hopefully, things will improve as the days get shorter and better conditions 
in late afternoon and early evening, the QRN begins to subside, and in a few 
weeks we will go back to real time.

A problem we may encounter as the bands get more active in the evening hours 
will be SSB QRM.  7285-90-95 is usually clobbered with broadcast signals 
during the evening hours, but 7160 is clear of broadcasting until about 
0400Z when the cat and mouse game between broadcasters and white-noise 
jammers starts up in Ethiopia and Eritrea, often wiping out everything from 
7155 to 7185.  7160 is usually excellent in the late afternoon and early 
evening, but it's also in prime DX territory.  I remember last spring, some 
of the SSB DX chasers would gripe about AM operating in what they considered 
their exclusive playground, and of course, there was plenty of adjacent 
channel QRM.  But this also gives us an opportunity to work Europeans on 40m 
phone.  Earlier in the year I managed to work a  few Europeans on 7160. 
They were on SSB, but said they could read my AM signal perfectly.  A couple 
of these stations even switched over to AM and we had two-way transatlantic 
QSOs.  If only some of the European group that meets on 3705 would give 7160 
a try...

The easiest way to grab 7160 for the evening is to start early before the 
activity gets heavy, call CQ if no AM is heard, and then continue the round 
table throughout the evening hours.  So far, I haven't heard the kind of SSB 
jamming we are so used to on 75m.

To the SSB DX chasers who gripe about AM on 7160 taking up too much of their 
precious DX space, my reply is that they should petition the FCC to extend 
the phone band down to 7100 or 7075 kHz.  There is very little US CW, RTTY 
or data activity above 7060, and when 7075-7125 is not vacantly lying idle, 
it becomes filled with foreign SSB. It is totally ridiculous that the 
continental USA remains the only country in the world restricted from 
operating phone in the prime DX segment.  Some die-hard CW enthusiasts want 
to hold on to that portion of the "CW band" at all costs, come hell or high 
water, but my response to them is "use it or lose it".  I rarely hear more 
than two or three simultaneous CW signals or QSO's in that whole 50 kHz 

Maybe the AM community should consider submitting our own petition to the 
FCC, but I would suggest waiting to see just how the 40m activity pans out 
this season, so we could formulate something well though-out, based on real 
observations, not just speculation over what "might" be.

Don k4kyv

This message was typed using the DVORAK keyboard layout.


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