Ssb Installation And Adjustment - Advanced Electronic Applications PK-88 Operating Manual

PK-88 OPERATING MANUAL
6. Press the
ous tone in the monitor receiver.
7. Tap the space bar several times until you hear the higher-pitched of the two tones
('Space' or Start Polarity).
8. With the PK-88 keying the transmitter, adjust the transmit audio level as follows:
o
o
9. Type [K]
10. Type [Q]
You have set your FM transmitter's deviation to the approximate level which will be
adequate for initial operation. However, an accurate setting will require a standard
FM deviation meter.
For best results with VHF/UHF transceivers at 1200 BPS, set the transmitter devia-
tion so that deviation on the higher tone does not exceed 4.0 kHz peak. With stand-
ard pre-emphasis, most transmitters will produce approximately 2.5 kHz deviation
on the lower (Mark/Stop) tone. Excessive deviation is likely to cause decoding errors
at the receiving station.
If your transmitter has an easily accessible microphone gain control, increase the
setting of the "deviation control" and reduce the gain of the transmitter microphone
circuit. This usually prevents excessive deviation limiting and bad mark-to-space
tone amplitude ratios.
11. With your radio in the receive mode, open the squelch control so that a steady hiss
or noise is heard on a speaker.
12. Set the receiver's volume control so the DCD LED on the PK-88 just lights with the
receiver unsquelched. This is the approximate proper audio level for best receive
performance from the PK-88's modem.
13. Reset your receiver's squelch control for normal operation.
14. Reinstall the cover and replace the four side screws.
2.8.4

SSB Installation and Adjustment

Installation and adjustment of the PK-88 with SSB radios is usually simpler and more di-
rect than with FM equipment. You will use the same kind of cable sand connectors that
you use with your FM gear.
Digital modes with an SSB radio require some different settings of the radio's operating
controls for proper packet operation. Be sure to observe the following precautions:
[K] key on the keyboard to key the transmitter. You should hear a continu-
Listen to the monitor receiver; turn the PK-88's internal AFSK Output Le-
veladjustment screw clockwise (CW) until you hear no increase in output
level
in the monitoring receiver.
Rotate the AFSK Output Level adjustment screw counterclockwise until the
audio signal on the monitoring receiver is noticeably reduced below the
maximum level.
again to return to the receive mode.
to 'Quit' (exit) the calibration routine.
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INSTALLATION
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