Note: The BigIR MK I - The original BigIR vertical antenna, can only handle 500w
with the coil
The BigIR MK II - Identical to the MK I except:
•
Longer copper tape guide inside the fiberglass pole
•
It can safely run 1500 watts output using the SteppIR 80m coil
The BigIR MK III - Internal and structural modifications
•
Moved the coax connector to a more convenient location
•
Unlike the MK II no internal jumpers are required to use the 80m coil
•
Easier to take portable and/or ship
•
Improved wind survivability - Un-Guyed 70 mph
- One Set of Guys 90 mph
- Two Set of Guys 110 mph
- High Wind Guy Set 125 mph
Bypassing the Coax Connector on the Element Control Unit:
This procedure bypasses the coax connector on your BigIR MK II allowing you to use the
ground stud on your BigIR MK II to connect your high voltage line from your 80m loading
coil so it can handle 1500 watts. The coax connector no longer serves any function after this
modification.
!!!!!!!!! CAUTION !!!!!!!!!
UNPLUG ALL WIRES AND COAX LINES FROM THE BIGIR
BEFORE DOING ANY MODIFICATIONS.
BigIR MK I (original model) & MK II Modification Procedure:
•
Remove the 10 (10x32) screws that hold the lid to the BigIR element housing unit.
•
Remove the lid and the housing gasket. We have supplied you with new hardware and a
new gasket for reassembly at the end of the 80m rewiring upgrade.
•
Locate the coax connector from the inside of the housing. You will notice two green
wires that are connected to the connector. One, the center line, that is connected to the
brush assembly on the platen. Two, the ground wire, that is connecting the ground stud
to the coax connector (Figure 3).
•
Cut both wires at the connector then trim them each to about 3” long. Strip 1/4” of insu-
lation off of each end of the two wires (Figure 5).
•
The wire connected to the brush must be moved on top of the platen so that it will reach
the other wire connected to the ground terminal. The splice will be located above the reel
and sprocket as it sits inside the housing. Also make sure that the wires are not touching
the sprocket or reel inside the housing (Figure 5).
SteppIR Antennas - 80m Loading Coil Kit
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