How to modify, repair, make better a commercial rotator
After I've bought and
repaired an old DAIWA rotator, I've decided I'll not buy a new rotator anymore....only
Infact now I've a DAIWA DC7011 and a YAESU G400RC both repaired and now 100% OK (better than a new one).
I'll describe some modifications (good for all rotator:YAESU G450 G600, KEMPRO.. ) to make your rotator better;
TOUCH" FOR THE BALL BEARING (See
the the body of rotator is in cast aluminum and often there are big defects on the plain; that make attrition to be higher and with the time rotator won't start;
In my YEASU G400RC there was only small defect but in my DAIWA that was terrible.
So I worked on it using at first an iron-file ending with a very soft one;
Make the same for the internal aluminum-gear.
INTERNAL SCREW CHANGE (See Fig 2);
The screw that fix the gear system to the body of rotator are not well-optimized for this use;
On my rotator there is a 2 el. Quad (see my web page) without a "rotator cage", so there's a little bit stress; with the time the above screws become slack so that the last gear wasn't really closed to the rotator body;
often my rotator didn't start: at first it was necesary a simple quick "left-right-left" with the switch but after months that was not enought and my rotator started only with the right wind !!
opened the case, i saw the screw become slack, so I've changed it with better ones.
EXTERNAL SCREW CHANGE : i've used Inox screw with higher head.
CHECK THE MOTOR BRAKE (See Fig 3);
observing the rotator motor when starts moving, you'll see its axle go up
for few mm and after down when stops;
at this point there is a plastic packing that act as brake; with the time it consume so, if necessary, change it.
MODIFY THE 500 OHM VARIABLE RESISTOR FOR THE POSITION
REPORT (See fig 4);
in my DAIWA DC7011 control box, after same years, appeared a problem: turning the beam the meter did't turn with it but moves "step by step"; the problem was the 500 Ohm variable resistor; infact in my Yaesu there was a wire connecting the central lead to the inside of resitor; in my DAIWA it was differenter; connecting a wire as above solves the problem (See fig 4).
MOVE THE MOTOR'S CAPACITOR FROM ROTATOR BODY TO CONTROL BOX (See
while in the YAESU G400 (as in most rotators) the motor capacitor is inside the control box, in my DAIWA DC7011 it was in the rotator body; that's not really important but if it goes off, you need to put down the beam, take down the rotator and change the capacitor;
so I think it's better the capacitor takes place in the control box (See Fig 5).
If the original capacitor goes off, you can use:
- similar-not polarized capacitor:
- make a new one using common electrolityc and two diodes.
FILTERING ALL INPUT/OUTPUT (See Fig 9): the cable that connect the control box to the rotator body is very "long" and acts as an antenna; and you know that RFI are very common in an amateur shack so it's a good idea to filter all the input output of control box using simple ferrite and by-pass capacitor; the picture show a recent modification to a GIOVANNINI ELETTROMECCANICA control box situated in Mike's shack (IK7UFR, OVER OVER) which control cables act as antenna for RF.
CHANGE THE SOCKET O THE CONTROL BOX REAR; that's not really necessary but I think will be better to have the possibility to hard-disconnect the control box - to - rotator cable during storms: lightning arrives not only trought the antenna's cable.
Follows various projects of rotator and control box:
73 de iz7ath, Talino