Re: Too Much Power

Posted by Joe Subich, W4TV-4 on May 26, 2018; 6:42pm
URL: http://elecraft.85.s1.nabble.com/Does-KPA1500-have-these-KPA500-characteristics-tp7641171p7641243.html


On 2018-05-26 2:11 PM, Joseph Reed wrote:
 > I agree it is a weak signal mode.

   ...

> Unfortunately the advent of FT-8 has introduced a large number of
 > individuals not brought up in the tradition of using low power to
 > communicate on a weak signal mode.

*WHEN* will people get it through their heads that WEAK SIGNAL is
not the same as low power?  The original "weak signal" mode is EME
yet almost 100% of EME work is done with high power - 1500 W on
CW and often 1000 W (or more) even with JT65 - plus extremely high
gain antennas (well in excess of the largest "stacked arrays" on HF).

*THERE IS NO "TRADITION" OF LOW POWER FOR WEAK SIGNAL MODES*

Conflating weak signal and low power is an artifact of PSK31/63/125
HF operation where lids run a 2 - 3 KHz wide passband or SDR rigs with
no RF/IF filters and then complain when strong, adjacent signals
overdrive their (cheap) sound cards or drive the IF/mixer/ADC of their
cheaply designed transceiver into distortion or overflow.

Use the same techniques that have been used for decades with *WEAK*
*SIGNAL* modes - narrow IF filters, strong preamplifiers, IF chains
with high compression levels, mixers with high IMD thresholds, etc.
- and there is no conflict between high transmit power and  weak
signal modes.

73,

    ... Joe, W4TV


______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]