JC-4s manual version 9.1 page 7
The 4 pin jumper is to select the output of the tuner.
Totally left :
Only output A will be used.
In the middle :
You can control output A or B remotely with the control box (default)
Totally right :
Only output B will be used.
Note :
If you want to use a 3 wire control cable with 1 antenna output you can use this jumper easy to
force to output A. To have the fun of 2 antenna outputs we recommend always to connect a 4
wire control cable. But if you use only a ladder line between A and B a 3 wire control cable will
do the job.
F: DIFFERENT ANTENNAS WICH CAN BE USED (just some examples)
1.
Vertical antenna 6.5 meters long (without a coil in series or in parallel connected to its base) for a
better performance in the upper HF bands or 12 meters vertical if we don’t care for frequencies
higher than 18 Mhz.
2.
Horizontal wire 25 – 28 meters, or 46 – 50 meters, with a diameter of at least 2 mm and a height
about 10m above the ground. For a real high performance, if we have the available space, it is
very good to place the wire about 20m above the ground, between two buildings. We note here
that anything that exists right below the antenna is considered as ground. So don’t go on believing
that if the antenna is placed 5 meters up from the roof of a building 20 meters high, the antenna
is 25 meters above the ground. The antenna considers the top of the building as ground!
