Support:
steppir.com/support
⚫
Tel: 425.453.1910
⚫
Page 44
CHAPTER TWELVE
SECTION 12.0
TROUBLESHOOTING THE URBANBEAM YAGI
TROUBLESHOOTING TIPS (continued)
With that in mind, the following are steps for checking the voltage between the pin pairs that feed the
motor windings. This information is critical to our technical support staff and you can save a lot of time by
having this data available before contacting us.
Instructions as follows:
With the DB
-
25 connector removed from the back of the controller, measure the voltage between the pin
pairs that feed the motor windings. For example, pins 1 & 2 and 3 & 4 when referring to the driven element.
The other elements pin pairs are listed in the troubleshooting guide These are the same pairs you use to
check the resistance of the motor windings
.
Be very careful not to short the pairs together or touch
any other pins in the process, or you can potentially damage the controller driver chips.
Having the 25 pin D
-
Sub splice assembly (see Section 3.0) generally reduces the chance of
damaging the controller while performing this test.
With the controller power plugged in, you should read approximately 3.5 VDC across each pin pair. At this
point, change bands using the controllers band change button. As an example, switching from 20m to 10m
generally gives a long enough run to get a good reading. You should be reading on your volt
-
ohm meter
approximately 20 to 25 VAC using a 24 volt power supply and 29 to 34VAC using a 33 volt power supply. To
check the next pin pair, you can then change bands back to 20m and so on through the wire pairs. If you
have significantly different values at any point in the test process, you can be reasonably certain that you
have a damaged driver chip for that element. 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 25 pin D
-
Sub splice assembly (see
Section 3.0
) when measuring the voltages, a
suggestion would be to use a bare 25 pin D
-
Sub 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 motors, and minimize
the need to calibrate the antenna on a regular basis.
The Director or Driven 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 consistent SWR reading.
2.
Select the Driven 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 element 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,
contact our technical support department for further instructions.
Further troubleshooting and support:
Additional troubleshooting information can be found at steppir.com/troubleshooting, including
troubleshooting guides for specific antennas.
General support can be found at steppir.com/support. You can scan the QR codes below to take you to the
troubleshooting or support pages.
Troubleshooting
General Support