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Tech Support:
www.steppir.com/support
⚫
Tel: 425.453.1910
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Page 77
Please be aware that in some cases, we have seen driver chips partially damaged, causing them to work
part of the time. This can be confusing in the test process.
If you do not have the optional 25 pin dSub splice assembly (see
Chapter Five, Section 5.2
) when measuring
the voltages, a suggestion would be to use a bare 25pin dsub to plug into the SteppIR controller and then
insert a paper clip to penetrate the pin hole. Usually about
.75″
long will do the trick. One paper clip being
longer than the other also helps. Again, be careful NOT to short the pins. Even if the controller is turned
off, there is always voltage going to the pins with a SteppIR controller. We do this to
“
lock
”
the stepper mo-
tors, and minimize the need to calibrate the antenna on a regular basis.
There is a defective coax jumper cable from the coax switch relay box output to the Director or
the Reflector
—our coax jumpers are manufactured by a company that specializes in these products, so a
defective jumper is relatively rare, but it has happened.
To check the coax jumper cable, measure the
resistance between the center conductor of the PL
-
259 on the each end of the coax. The coax jumper
should measure a very low resistance of 3 ohms or less (has continuity). If the coax jumper has high
resistance (no continuity), there is likely a problem with it.
There is a defective relay inside the coax switch box
—
relays are mechanical devices so there is al-
ways a chance one could be defective, although we test all coax switch boxes before they leave the factory.
Refer to
page 51
-
53
for the relay test instructions.
The coax relay box is not switching due to a defective relay or the relay switching voltage is
somehow not getting to the relays—
this could be due to a defective control cable, a broken wire or a
defective controller relay board. Refer to
page 51
-
53
for the relay test instructions.
The Director or Reflector element is not tuning, or tuning intermittently
—This could be a defective
control cable, controller driver chip or a defective EHU. If you have already tested for these potential issues
and to verify if the EHU is actually tuning, follow these steps:
1.
Go to "Create/Modify" in setup mode and apply enough power to get a good SWR reading.
2.
Select the Reflector element and change its length about 15
-
inches and see if you see a difference in
SWR. It doesn't matter if the SWR improves or gets worse as long as it changes. This indicates the ele-
ment is tuning.
3.
Select the Director element and repeat the above steps. If the SWR changes the element is moving.
If the EHU looks like it is not moving and you have already done all of the wiring checks in this section, con-
tact our technical support department for further instructions.
CHAPTER TWELVE
SECTION 12.0
TROUBLESHOOTING THE DB18E YAGI (continued)
TROUBLESHOOTING TIPS (continued)