QRP Labs 10W HF Linear PA, Инструкция по сборке

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10W HF Linear PA kit assembly 1.00
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Observe the current consumption on the current meter.
Adjust one trimmer resistor, turning it very carefully and slowly clockwise, and look for a current
INCREASE (on top of the observed initial current reading) of 125mA.
Adjust the other trimmer resistor, again very carefully, for a further increase in current consumption
of 125mA.
Once both PA transistor bias has been adjusted for 125mA (total 250mA) this sets up the Linear
Power Amplifier for optimal performance operation.
4.4 Tests undertaken
The following tests were undertaken by Allison KB1GMX on a production unit. They have been
reproduced on three different kit assemblies.
In all of the tests, there were no failures of components and no degradation of
performance.
1) Gain: 26 to 28dB, with +/- 1dB gain flatness over the range 2-30MHz. This is shown in the
following images.