RESEARCH CONCEPTS RC2000A DUAL AXIS Instructions Manual page 110

with the smaller 'on satellite' – 'off satellite' voltage difference to the controller's AGC1 input.
Connect the other receiver's Signal Strength output to the controller's AGC2 input.
4. If the AGC voltage associated with the 'on satellite' case is greater than that of the 'off satellite'
case, the receiver has POSITIVE AGC polarity (otherwise the receiver has NEGATIVE AGC
polarity). Go to CONFIG mode and use the SCROLL keys to bring up the AGC Polarity Flag item.
Key in the proper polarity using either the 0 or 1 key, and terminate the entry with the ENTER key.
5a. If two receivers are interfaced to the controller proceed to step 6. If the receiver's AGC has
NEGATIVE polarity, go to step 5b. If the receiver's AGC has POSITIVE polarity, from MANUAL
mode use the Scroll Up/Scroll Down keys to examine the signal strength for the AGC channel which
was NOT selected in step 3. If the signal strength reading for that channel is greater than 10, adjust
the OFFSET and GAIN for that channel until the signal strength reading for that channel is less than
10. To lower the displayed signal strength turn the OFFSET pot clockwise and the SCALE pot
counter-clockwise. Proceed to step 6.
5b. If the receiver's AGC has NEGATIVE polarity and only one receiver is interfaced to the controller,
connect a jumper from the controller's unused AGC input channel to connector J1, pin 11. From
MANUAL mode use the Scroll Up/Down keys to examine the signal strength for the AGC channel
which was not selected in step 3 above. If the signal strength reading for that channel is greater
than 10, adjust the OFFSET and GAIN pots for that channel until the signal strength reading for that
channel is less than 10. To lower the displayed signal strength value, turn the OFFSET pot
counter-clockwise and the SCALE pot clockwise. When this is accomplished proceed to step 6.
6. In the next few steps of the procedure, the OFFSET and GAIN pots of the AGC channel(s)
connected to the receiver's AGC output are adjusted so that the 'off satellite' signal strength value is
between 50 and 100 and the 'on satellite' signal strength value is between 600 and 700. The
adjustments are made from MANUAL mode. Note that the GAIN and OFFSET adjustments are
implemented using 20 turn pots. A lot of turns may be required.
To adjust the potentiometers, several quantities have to be identified for each receiver.
If the controller has NEGATIVE polarity, go to step 6b. For POSITIVE polarity AGC, the installer
needs to identify the satellite band (C or Ku) that resulted in the greatest 'on satellite' voltage
(strongest on – satellite received signal) and the least 'off satellite' voltage (weakest off satellite
signal).
In step 1, the 'on satellite' AGC voltage was recorded for both C and Ku bands. Which voltage was
larger, C or Ku? ____. In the following steps, when instructed to position the antenna 'RCV1 - on
satellite – strong band' align the antenna with the ____ Band satellite found in step 1 (use the band
specified at the end of the previous sentence).
In step 2, the 'off satellite' AGC voltage was recorded for both C and Ku bands. Which voltage was
smaller, C or Ku? ____. In the following steps, when instructed to position the antenna 'RCV1 - off
satellite – weak band' align the antenna with the ____ Band satellite found in step 2 (use the band
specified at the end of the previous sentence).
If both controller AGC inputs are utilized, record similar values for 'RCV1 – on satellite – strong
band' ______ (C or Ku band) and 'RCV1 – off satellite – weak band' _____ (C or Ku band). If both
controller AGC inputs are utilized steps 7 through 9 must be performed for each AGC channel. Use
the Scroll Up/Down keys to view the AGC channel whose pots are being adjusted.
6b. For NEGATIVE polarity AGC, the installer needs to identify the satellite band (C or Ku) that resulted
in the least 'on satellite' voltage (strongest on satellite received signal) and the greatest 'off satellite'
voltage (weakest off satellite signal).
In step 1, the 'on satellite' AGC voltage was recorded for both C and Ku bands. Which voltage was
larger, C or Ku? ____. In the following steps, when instructed to position the antenna 'RCV1 - on
satellite – strong band' align the antenna with the ____ Band satellite found in step 1 (use the band
specified at the end of the previous sentence).
In step 2, the 'off satellite' AGC voltage was recorded for both C and Ku bands. Which voltage was
smaller, C or Ku? ____. In the following steps, when instructed to position the antenna 'RCV1 - off
satellite – weak band' align the antenna with the ____ Band satellite found in step 2 (use the band
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