Roger (K8RI) wrote:
> Jim Lux wrote:
>> Dave Harmon wrote:
>>
>>> Believe me.....the airport considerations are the LEAST of your
>>> potential
>>> and likely problems with a tower of any kind if you are in a
>>> sub-division or
>>> 'village' or 'township'.
>>> Any location where you must sign your rights away will probably make it
>>> impossible to do any HF operating of any quality.
>>>
>>
>>
>> Nonsense... You might not be able to use 1940s and 1950s technology
>> (i.e. a Yagi on a big tower), but from a theoretical standpoint, you
>> should be able to do almost as well from a 50x100x20 foot cube with
>> visually inconspicuous/invisible radiators.
>>
>> The challenge to hams is to do "HF operating of quality" within the
>> constraints of modern civilization.
>>
> To me the key is "Acceptable constraints".
I agree.. but the meaning of "acceptable" tends to vary, both
geographically and over time. And, we shouldn't think that if one is
constrained by circumstances to be unable to use a tower and beam that
all is lost.
> Every thing I've enjoyed through life seems to be under attack. The
> neighbors want to close the airport,
<snip>
> Yes, I even feel constrained by a 200 X 200 foot lot and a 1000 sq ft
> home, but I can afford what I have. I'd be actively hunting for 4 to 6
> acres to either by with a home or build on were I 20 or even 10 years
> younger.
>
> However I see the same attitude of staying put and fitting in, costing
> thousands of jobs. People complain about the computer system jobs going
> overseas but at the same time I see the industry clamoring for a big
> increase of the (think it's S-1 Visas) because there are literally
> thousands of very high paying jobs going begging as they can't find
> qualified people to fill them.
I would advocate a multi-pronged strategy.. On the one hand, discourage
additional restrictions (by means of practical demonstration and
traditional persuasion, just as you have), but also, push the technology
forward. (if for no other reason than if you have a world beater
technology in a 50x100 ft that's visually inconspicuous, it might be all
the better on a 10 acre salt water marsh)
Pushing the technology doesn't imply giving up on the old model.
>>
>> I'm sure the folks contemplating operation from a suburban lot with a
>> Yagi back in the 40s and 50s were probably told "if you don't have
>> room for a multiwavelength rhombic, you might as well be operating
>> portable on batteries"
>>
>>
> I don't remember any one telling us such, but it's a fact of life, the
> better the antenna the easier it is to get out. OTOH I never have liked
> Rhombics. <:-)) If some one wants to, or finds themselves in the
> situation where it's necessary to use limited space, low profile
> antennas and have the desire to build the skills necessary for lower
> power, limited space antennas I think that is great, but it's not for
> me. Yes I believe in building skills, but not unnecessary handicaps.
Not really skills per se... I'm looking for advances in technology
flowed into the amateur market. From adversity comes creativity, in
some cases.
>> And, of course, "nobody will ever use that newfangled sideband stuff"
>>
>> I think that the era of "big tower with a 3 element yagi in the
>> backyard" is on its last legs, just like the multi-acre "antenna farm"
> Around here we are seeing more and more larger towers and antennas.
>
>> of yore (e.g. W6AM's installation). Of course, there will always be
>> folks with the resources to have the field of rhombics or the multi
> I never could figure out whey any one would put up a rhombic when they
> could get nearly the gain and much more flexibility out of a Yagi.
Because back in the day, the commercial operators had fixed links, so an
array of rhombics worked pretty well. W6AM just inherited an old HF
commercial site. And these sites were built in pre-Yagi days (before
WWII)... Once you've done the investment, why change?
>>
> I really thing ham radio should be high profile except in those
> instances where CC&Rs prevent it .
> I want the neighbors to know who and what I am. To do otherwise does
> the Amateur Radio Service a dis-service.
Indeed.. however, in life one makes tradeoffs in where one can live.
Relatively few folks get to make ham radio their primary purchase
criteria. If technology can make a silk purse of a station out of a
sow's ear of a CC&R location, all the better. In fact, I would contend
that there is a market for such things (although, perhaps, not
sufficient to justify investment in development) since many folks might
be willing to spend significant amounts on such technology, if it allows
them to also take advantage of the advantages (such as they are) of the
CC&R controlled area.
Someone who is willing to spend $50-100K on landscaping to make their
yard prettier and more useful might well be willing to spend a
comparable amount on a low profile, but effective, radio system.
>>
> Rigs?Yes, and test equipment, but I think the term hardware is a bit too
> broad.
Well... The technology is sort of there, just not in a form amenable to
amateur use (at least without requiring a substantial investment of
independent development time).
So it comes to the market desires and what's available.. the
tower/yagi/rotator business provides solutions to all levels, from
scrounger using surplus parts, to self-erector and integrator buying the
pieces new and assembling and erecting, to a "write the check and be on
the air" turnkey operation.
The same is not true of, say, an active phased array. It's at the
self-builder/scrounger stage.
>> Pretty much the only theoretical advantage of the tall tower (and it's
>> a
> It's not just theoretical although 60 to 70 feet is plenty for 20
> through 10. It's kinda short for 40, really short for 75 (I need more
> than that just for half wave slopers.) and minuscule for 160. Sure you
> can work out fine with much less. There are QRPers doing it all the
> time with low power and small antennas. Many do it for the challenge.
> OTOH for VHF and UHF the taller the better. However I can't see doing
> it just to please the neighbors.
I didn't mean that the advantage is only theoretical.. It's that
theoretically, one can do almost as well as the big tower without it,
but it's not simple.
>> significant one) is that you can get more radiated power into the far
>> field in a particular direction with a limit on transmitter power, and
>> that's mostly because of the soil properties a few wavelengths away.
>>
>>
>>
> And it also works on receive.
Indeed..
Actually, what I might get interested in is doing away with the 1500W
limit, and having a limit on radiated E-M field strength (recognizing
that there are significant practical problems with such a regulatory
approach<grin>)
If power were unlimited, then you could make up for tower height with
watts into the antenna. Spend your dollars (or visual impact brownie
points) on either a tower or on an amplifier.. that's the sort of system
trade that is quite common in the rest of the communications world where
one might trade off transmitter power, antenna size and receiver noise
figure. One can argue that part of the "skill" in amateur radio is
doing the best one can with 1500W, but as you point out, that's an
artificial limit. There's no reason, other than tradition, why hams
should be limited to 1500W or 100W or 150kW or any other power. (In
fact, it would be interesting to know where the original 1kW DC power
input rule came from.. i.e. what was the regulatory basis for it..maybe
someone knows?)
(one would also probably need to deal with safety, too.. that 10kW
transmitter into the small loop antenna to radiate 100W, aside from
heating up the soil and antenna, might also create a fairly strong EM
field in places where people and animals are)
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