KPC-9612 Version 5.2 July 19, 1994
61
Calibration/Equalization
The CALIBRAT command is used to assist in adjusting the transmitter deviation and also in adjust-
ing the receive equalization of your KPC-9612. The procedures listed below are a guideline for us-
ing the calibration command to adjust the 1200 baud port and 9600 baud port for optimum per-
formance.
1200 baud adjustment
You must have your current I/O stream on the 1200 baud port. When you issue the CALIBRAT
command, the following options will appear on your terminal screen:
1200 CALIBRATE MODE: PRESS M,R,S,T, OR X
Pressing M will transmit a constant MARK until a key is pressed. Pressing R will measure a received
square wave. Pressing S will transmit a constant SPACE until a key is pressed. Pressing T will
transmit a square wave (space/mark) until a key is pressed. Pressing X will exit the Calibrate Mode
and reset the KPC-9612.
After entering CALIBRAT Mode for the 1200 baud port, you should use the T option to transmit a
square wave and adjust the APSK drive (R-22 and J5) for approximately 3.5 kHz deviation from
your radio. This will set the proper drive level for your transmitted signal.
If you have another Kantronics user close to you, have that station transmit a CALIBRAT square
wave and choose the R option in your Calibrate Mode to adjust your receive equalization. You will
see two numbers displayed each time you press R.
The KPC-9612 is measuring the space/mark square wave generated by the other station. For best
equalization on your receive signal, these two numbers should be as close to equal as possible.
In most instances when the ratio of the numbers is within a 40/60 or 60/40 range, the packet sta-
tion will function normally. A larger disparity in the tones may cause additional retries during pack-
et operation. The ratio may be determined by the following formula:
(N1 × 100)/(N1 + N2)
where N1 is the number to the left of the displayed slash, and N2 is to the right of the slash. For
instance, if the displayed numbers are 1400/1800, the ratio can be determined by:
(1400 × 100) / (1400 + 1800) or 140000/3200 = 44
Since the total is 100, the ratio is then 44/56 and is within the 40/60 criteria. If the ratio of the
numbers exceeds the 40/60 or 60/40 value, you should move the internal equalization jumper (Jl).
This jumper is shipped from the factory on both posts for no equalization. Placing the jumper on
one post only enables partial equalization. Use the setting that gives the closest to 50/50 ratio.
9600 Baud Calibration
You must have your current I/O stream on the 9600 baud port. When you issue the CALIBRAT
command, the following options will appear on your terminal screen:
9600 CALIBRATE MODE: PRESS B,R,T, OR X
To Next Page
Loading...
Need help?
General
