Mini-Loop MFJ-1788 — Inside the Weather Cover

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Environment.
Coil part and mounting mechanism.
The feed point.

The horizontal elliptical --22cm*13cm-- gray cable is the feed loop.
The other one is for the motor in the opposit shell:
+9V from the black line to white one (behind the coil) means "up;" while +9V from the white to the black means "down."
I had to shorten the coil by 1cm (or 1/2 in) to tune the anntena for 21MHz band.
The VC.

The capacity is
- the minimum, at his highest frequency (21MHz); and
- the maximun at the lowest (7MHz).
"+/- 9V" DC is fed to drive the motor through the gray cable.
The diameter of the VC is about 12.5cm (5in).
The VC is composed of alminium blades.
The hook is installed on the shaft as a stopper (see below).
The main board has two stop switches for each rotative direction.
The motor. It includes a geer box inside.
This motor made by "Hankscraft Motors" includes total 6-stage gears inside the black case and provides 0.5rps @12V.



Main board's first surface.
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