Asymod BT-HPSA V2, Instruction Manual

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Set up
The Asymod
HPSAV2 for TX

Turn all controls to minimum - CCW (counterclockwise position).

Key the transceiver using the PTT switch connected to the PTT connector,
whether a mouse, foot pedal or other and raise the CARRIER control while
observing the RF power meter to the desired carrier (dead key) level not to
exceed 10 W unmodulated carrier.

Once the carrier level has been set, adjust the oscilloscope’s volts-per-division /
vertical deflection to cover TWO vertical divisions as a reference to later
measure the modulation envelope.

Set a signal generator to a 1 kHz tone at 1 VPP to the LINE IN input. This can be
easily done if using PC based audio processing with a built in signal generator for
the audio process chain.

Key the transceiver and raise the MODULATION control until the negative peaks
approach -99% and the positive peaks reach +100%. At this point you should see
the peak indicator come on.

At this point the transmission is set for 100% modulation and the modulation
envelope’s vertical deflection will be covering FOUR vertical divisions at the
peaks. TWO divisions above the 0 volt line and TWO divisions below the 0 volt
line at the peaks.

To raise the modulation percentage beyond 100% modulation, slowly raise the
ASYMMETRY control while observing the modulation envelope on oscilloscope.

When the modulation envelope peaks reach THREE divisions above the 0 volt
line and THREE divisions below the 0 volt line at the peaks the modulation will be
at 200%.

To further raise the modulation percentage beyond 200% modulation, slowly
raise the ASYMMETRY control while observing the modulation envelope on
oscilloscope. When the modulation envelope peaks reach FOUR divisions above
the 0 volt line and FOUR divisions below the 0 volt line at the peaks the
modulation will be at 300%.