FIGHT? Here is another W8JI myth bone!
"Richard Harrison" wrote in message
...
Yuri, K3BU wrote:
"Electrostatic shields work on principle of capacitance plate, being
grounded and side exposed to electrical/electrostatic fields."
Terman on page 1049 of his 1955 edition writes:
"Such a shield ensures that all parts of the loop will always have the
same capacitance to ground irrespective of the loop orientation in
relation to neighboring objects."
Yuri is consistent with Terman, and that is liable to be better than a
bible because it is provable and demands no faith. If wrong, it will be
rewritten with corrections.
Best regards, Richard Harrison, KB5WZI
Richard,
thanks for the reference and support, coming from one who had his hands
"dirtied" with the antennas.
Terman also says just a sentence befo
"Errors from unbalance can be minimized by using circuit arrangements
that are symmetrical with respect to ground, such as shown in Fig. 26-27b.
It is also helpful to enclose the loop in an electrostatic shield, such as
metal housing broken by an insulated bushing, as show schematically in Fig.
26-27c."
and then sentence quoted above.
Clearly, the shield is functioning as an electrostatic shield, providing
symmetry and is not acting as "W8JI Antenna". Loops are the antenna, shield
is the SHIELD, contrary to W8JI proselytizing.
Small loops are the antennas, with or without the shield. Electrostatic
shield is a shield, provides symmetry for the antenna and helps to reject,
shunt the interference from the sources in the proximity of the antenna by
its virtue of the capacitance to the ground.
Terman didn't say: "yo stupid, you don need no stinkin' loops, jus' use the
shield as antenna" :-)))
73 Yuri Blanarovich, K3BU
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