On 2021-04-03 9:02 AM, Wilson Lamb wrote:
>
If you find the right contractor, you can get control transformers
out of old air conditioning units, usually 120V to 28V,
Depends on the current rating of the surplus transformers. You would
need at least 5A on the low voltage side. Given the dual winding
nature of the Hy-Gain rotors you would also need *six* transformers
(two for the brake (1/2), two to rotate CW (5/1), and two to rotate
CCW (6/1)). The motor run capacitor (4/8) would need to be relocated
to the tower.
The other option is to use one pair of 8A transformers (step up/step
down) on wires 1/2 (brake and motor common) and a couple of 24 VAC
relays (at the tower) to control rotation (again with the motor run
capacitor relocated to the tower).
In either case, be careful to bring wire 1 back unbroken as it is also
used for the direction indication.
Years ago the solution for Hy-Gain rotors was to use a surplus 5 - 6.3V
(filament) transformer to "boost" the 24-26V. Connect the primary of
the additional transformer in parallel with the primary of motor/brake
transformer and connect the secondary in series with the "ground" lead
from the brake transformer secondary to terminal 1 (common to motor and
brake). Make sure to check the brake voltage for boost instead of buck!
73,
... Joe, W4TV
On 2021-04-03 9:02 AM, Wilson Lamb wrote:
How about using transformers to raise the voltage for the long run and again at
the tower, to go back down.
You could use at least 120V, but likely even 240V.
If you find the right contractor, you can get control transformers out of old
air conditioning units, usually 120V to 28V,
They often show up at hamfests too.
Wilson
W4BOH
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