Re: Non-ultralight owner question(s)...


Michael <michael.setaazul@...>
 

On 01/05/2011 8:46 AM, airchecklover wrote:


A 1 khz DSP-defined bandwidth? The advantage of a "super-Q" homebrew long
ferrite antenna? In my experience, a 2.3 khz "SSB filter" is almost
too narrow for intelligible Amplitude Modulation (AM) recovery while a
1 khz "CW filter" is too narrow. Yet I'm seeing reports of stations at
909 khz or 1089 khz or 1341 khz. How is this possible? Is there
something about the DSP filter - with perhaps super-steep skirts that
is allowing for this? But still, a 1 khz RF passband is not going to
allow more than 1 khz audio, which is too narrow to discern anything
more than vowels (ie, no consonant differentiation possible). Or have
I been a student of theory too long and simply need to 'try it'??
************************************************************************************


Hi Mark and all,

We we all agree with Robs points. Most of the time, it boils down to
luck, propagation and interference. The 1 or 2 kHz bandwidth
is, as you surmise, a bit like pass-band tuning, as in my old R4B.
Judiciously placed, a signal can become intelligible, where wider
or a little higher or lower, it becomes unreadable. The kick is a bit
like qrp getting through the kilowatters. Im in the UK close to the
sea (next stop: Cape Cod) so likewise have an "unfair advantage" :-)

Try a Sony SRF-59 cheapo, a Tecsun PL-380 or similar to start with.
You will, of course, find lots of info on the uldx website.
The best advice is probably your own last line above!

73s

Michael UK
formerly 9Q5TS

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