[Amps] rich Richard - tiny antenna

[Jim Brown]

On Sun,4/9/2017 8:24 PM, Steve Wright wrote:
> Surely most multi-band yagi's, 1/4y verticals, plain ol' dipoles, and
> any other competitive HF antenna that you would WANT to poke some
> horsepower into is gonna have <1.5:1 SWR?

At one frequency, perhaps. But it takes some real tricks (good ones) to 
get a dipole apparent SWR (as read at the transmitter) under 2:1 for 400 
kHz of 80/75. Ditto for 160M.

>   Maybe you alligators want to
> tune up your half size g5rv on 160M or similar?
>
> It's almost as baffling as the fixation with IMD..

IMD is a VERY big deal if you care about not making a mess on the band 
when you transmit. IMD ==> wide clicks on CW and splatter on SSB. If you 
read FCC Rules, it says that we must use the minimum bandwidth required 
for the mode of transmission. Since Elecraft introduced their P3 
spectrum display (almost a lab quality instrument, by the way), I'm 
repeatedly disgusted (and QRMed) by many of the dirty signals I hear/see.

A disgustingly large number of SSB signals have almost as much splatter 
in the bandwidth of their suppressed sideband, and an equal amount above 
where the sideband filter in the rig cuts off. That's ALL IMD, much of 
it in the amps, but some in the rigs themselves. Causes include the 
output device driving a mismatch, overdriving the amp, driving the amp 
at full output of the rig and letting ALC throttle it back, and even IMD 
produced in the rig itself through bad design of "processing" that 
includes the RF chain. W4TV has written about this.

K6XX taught me that a mis-tuned amp (or a solid state amp working into a 
mismatch load) produces a lot more clicks and splatter than one that is 
properly tuned. We're both serious contesters, and when I moved in 3 
miles S of him, he made damn sure that I knew how to tune my Titan amps. 
Bob is an engineer working at Elecraft, where he works as a production 
engineer. As a result, we can work with 500 Hz of each other on CW at 
legal limit and hear the other as simply another strong signal, and 
easily work fairly weak signals. We're both running tube amps.

>    Isn't the goal to get on the air, work some DX and bend some jealous locals' S-meters?

I'm and old fart, and when I was young, I was taught that with rights, 
we have responsibilities. We have the right under FCC Rules and our 
license to run big power to big antennas, but we also have the 
responsibility to keep our signal CLEAN.

> Cmon people..  Make a resonant antenna already!

I'm a VERY strong believer on that score. All of my TX antennas (about a 
dozen) are resonant.

On a separate topic, sort of -- the amp sold for use with the 6700 Flex 
can run SO2R. For those who don't contest, that means there are two 
radios on different bands, and one radio is always calling CQ while the 
other is listening. Or, when things get slow, dueling CQs. Think about 
this with RTTY -- it could be damn near solid keydown at the end of a 
contest when you've worked almost everyone. The Flex 6700 is set up so 
that that single radio can function as two complete receivers, and 
transmitters than can be switched between two outputs. If a single amp 
like the one announced does SO2R, it's going to see a duty cycle that 
approaches twice that of an amp connected to only one of those outputs.

As to CCS and ICAS -- it's been a long time since I've looked at the 
definition, but CCS clearly means that you turn the transmitter on and 
it stays on 24/7. Think broadcast, or a repeater that stays up for very 
long periods. As I recall, ICAS means intermittent commercial and 
amateur service. But I could be wrong. And these ratings are for the 
output devices, which when I was knowing about it, were hollow state.

73, Jim K9YC