Sailor COMPACT HF SSB T2130, Technical Manual

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2 INSTALLATION MECHANICAL HF SSB TRANSMITTER T2130
STATE 2
In this state the RF-level is increased one step at a time and compared to 2 different levels:
- Vf_max.
If Vforward is higher then the automatic power setting continues at state 3.
- The previous measured Vf 0.12 dB.
If Vforward is lower then the automatic power setting continues at state 3.
Else state 2 is repeated.
This specification compared to the previous Vf 0.12 dB is performed to ensure that the
increasing of the Vforward is stopped if there has been an increase less than 0.12 dB. This may occur
when the Power Amplifier (1) has begun cumpressing the signal. The compressing of the signal gives
distortion and reduces the intermodulation.
STATE 3
This state is run when the Vforward was measured to be one step too high. RF-level is reduced one step
because the previous level was too high.
Depending on which event has started the automatic power setting the RFlevel is reduced further. If an
AT2110 is in the system, (jumper 5 is not inserted) Vforward is further reduced 20 steps (approx. 6 dB)
in order to protect the Power Amplifier (1) while tuning the AT2110.
CALCULATING VFORWARD MAXIMUM
Vf_max is compounded of 4 parameters:
- A value (Vf_max1) calculated from the Vforward - Vbattery equation (the graph in fig. 1).
- An addition (Vf_max2) as a result of the calibration. The calibration procedure is described in section
2.3.3.5 CALIBRATION OF THE T2130
- An addition (Vf_max3) related to the frequency.
- A reduction (Vf_max4) because of reduced power.
Vf_max is found in the following way:
- Vfmax5 = V V Vf_max3
- Vf_max = the lowest of Vf_max4 and Vf_max5
In the following the parameters are described separately.
Vf_max1 (VFORWARD - VBATTERY EQUATION)
The Vforward maximum is depending on the present Vbattery. The graph in fig. 1 shows the coherence
of the Vbattery and the maximum allowable Vforward.
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