Telling on myself . . .

Status
Not open for further replies.

KB2GOM

Active Member
Joined
Jun 1, 2020
Messages
613
Location
Rensselaer County New York
While waiting to start the Commuter Assistance Net on 2 meters this am, it seemed like a good time to see what happening on the HF broadcast bands. So I grab the CCrane Skywave SSB, extend the whip antenna, and press and hold the DOWN button to start it scanning from 10 MHz downward. (the Skywave SSB has a slick trick: if you are in AM mode, it will hop from international broadcasting band to international broadcasting band as it is scanning; if you are in SSB mode, it will hop from ham band to ham band while scanning.)

Presently, the Skywave stops on 5955, and I can hear a broadcaster, fully copyable but in the noise. Wondering what the signal sounds like on the Satellit 800, I switch it on and punch the frequency. Nothing. Nothing? Really? Maybe my horizontal room loop antenna is deaf on that frequency. I switch the Satellit to its whip antenna. Still nothing. Weird. Can it be that the Skywave with a whip antenna is actually more sensitive than the Satellite hooked to 50 feet of wire?

Then I tune the Satellit to 5950; big, fat signal. Clearly the Satellit has better selectivity than the Skywave, which stopped scanning at the edge of the signal. Tuning the Skywave to 5950, the signal is better, but still lots of noise. Engaging SSB and narrowing the bandwidth, the signal comes nicely up out of the background.

Note to self: don't make assumptions about what's working or not working, and learn to use the tools at hand.
 

popnokick

Member
Premium Subscriber
Joined
Mar 21, 2004
Messages
2,837
Location
Northeast PA
You're going to want to pay close attention to the bandwidth setting that is in effect on your radios. For the Skywave SSB this is addressed on p. 15 of the CCrane manual. For the Grundig Satellit 800 it is on p. 25. When you have a particular bandwidth set (either deliberately, accidentally, or "automatically" in the case of the Satellit) a narrow bandwidth setting can cause you to "miss" a station. Which based on your description is what you just experienced with the difference between tuning 5950 and 5955 kHz. If the receiver bandwidth settings were different on each radio, then "missing" something on the other radio is entirely possible. Most of the time this will work to your advantage when you are trying to "notch out" a station that is adjacent to the frequency of the desired station which you are trying to hear. This adjustable "interference rejection" (bandwidth) is normally a desirable characteristic for any receiver. And both of your radios handle the bandwidth settings... and indications on the display.... very differently (as explained in the manual pages I referenced). Be certain you are aware of your bandwidth settings, particularly when comparing what the radios are hearing (or not).
 

Boombox

Member
Joined
Sep 2, 2012
Messages
1,366
I never have used the 'scan' or search function on any SW portable. I search down each band manually, so I've never had that issue.
 
Status
Not open for further replies.
Top