RadioBanter - Make your own T2FD

RC (KB7QHC),

Spoken (written) like a True Amateur, and precicly why most SWLs
ignore what is written in reply to SWL 'type' Antennas questions
by HAMs.

Most SWLs work to get the best signal (cleanest signal and lowest
noise) they can to be able to listen to what they what to hear.

The HAM would hardly ever consider a 'random' wire Antenna;
but to the SWL'er the "Random" Wire Antenna 'concept' is a
natural to fill their available space. Power handling, gain
and antenna design characteristics are the focus of the HAM.

As far as the AM/MW Loop Antenna's are concerned. For the AM/MW
DX'er these Antenna's perform the best for their size and the
available space that the average Broadcast Listener (BCL) has
for these Medium Wave Band. The SWL'er wants to hear any Radio
Station out there from any direction.

The 'focus' of the SWL'er is simpy different then the Amateur;
and the majority of SWL'ers are Program Listeners who seldom
listen to the HAM Bands.

iane ~ RHF
..
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= = = Richard Clark wrote in message
= = = . ..
On 28 Jun 2004 17:19:51 -0700, (RHF)
wrote:

RC,

In the same location using the same Antenna:

100uV of background noise being re-radiated by a Transmitting
Antenna that is being powered at 50W or 100W is simply not an
issue for the Amateur/HAM.

Hello iane,

The construction of this "argument" is called a strawman. Who is to
say it "is simply not an issue?" Further, who is to say it is?
Amateur radios, as last I noted, contain receivers too and suffer
every much any debility as a SWL set. Simply put, there is no
separation to argue.

- Background Noise is NOT an Issue when thinking of Transmitting
Antennas that are Radiating Power in the Tens and Hundreds of Watts.
- For the HAM Signal-to-Noise is NOT a Transmission Antenna Parameter.

Then why would you presume this is a fault in discussion here in an
antenna group? True this is cross-posted, but again, we have every
concern with reception that a SWLer would also have. Again, there is
no separation of issues to argue.

100uV of background noise being received by a Receiving Antenna
that is seeking a 25uV Signal is unacceptable for a SWLer.

Again, Amateur radio is just as concerned and seeks every remedy where
ever it may be found. To continue:

- Background Noise IS an Issue when thinking of Receiving Antennas
that are 'acquiring' Radiated Power in the Milliwatts or micro-watts.
- For the SWLer Signal-to-Noise IS a key Receiving Antenna Parameter.

Antennas have no capacity to reduce Signal to Noise ratios except by
virtue of narrowing lobes to eliminate noise by placing it in a null
(if that is in fact a viable option either in the sense of having a
null, or having a null to a noise source that is not on the same
meridian as the signal of interest).

To this point, you have not offered any particularly receive dominated
issue that is not already a heavily trafficked topic with transmission
antennas. In fact, the presumption there are unique reception
antennas that are more suitable than their transmission cousins is
simply the artifice of my aforementioned advantage of the RF Gain
control. It has been long established (through the simple act of
purchase power) that receivers have far more gain available than
needed except for the worst of antenna designs (and that has to be an
exceptionally vile design).

Such examples of small loops used for MF are proof positive how poor
an antenna can be, and the RF gain knob resurrecting its pitiful
efficiency. This does NOT demonstrate some illusion of superior
receive antenna design; rather it is more smoke and mirrors as an
argument. Inverting the argument, if you had a full sized antenna for
that band, you would only need a galena crystal and cat whisker to
power your hi-Z headset. For DX you would only need a $5 AF
amplifier. The smaller antenna clearly needs more dollars expended to
offset the debilities of the poorer efficiency. The specious argument
is tailored for the technically effete who would rather push a credit
card across the display counter than build their own cheap solution.
Take heart that this not simply a cheap shot, there are as many Hams
who don't know which end of the soldering iron to pick up either.

73's
Richard Clark, KB7QHC