QCX assembly Rev 1.08
98
If a GPS unit is available, then this makes everything very simple
– then you can use the GPS
calibration tools to calibrate this value (see below).
8.6 System frq
20,000,000
The system oscillator frequency. In this radio, the microcontroller clock is a 20MHz crystal. If you
are able to measure the actual 20MHz frequency (without disturbing it), you can enter the
frequency here. You could, for example, listen for the 20MHz radiation on a general coverage
receiver whose frequency indication you trust.
The 20MHz system clock is used for timing purposes only. It is not very critical, unless you intend
to operate the WSPR beacon function without a GPS.
If a GPS unit is available, then you can use the GPS calibration tools to calibrate this value (see
below).
8.7 Peak BPF
Press Select!
Pressing the left (select) button activates the signal generator on the configured frequency and
displays a bar on the screen showing the measured audio amplitude at 700Hz. The Band Pass
Filter trimmer capacitor should be adjusted for maximum measured amplitude. This process is
described in the earlier section “Adjustment and alignment” at the end of the assembly part of the
manual.
8.8 I-Q bal
Press Select!
Pressing the left (select) button activates the signal generator on the configured frequency with an
offset to put the received signal in the unwanted sideband. It displays a bar on the screen showing
the measured audio amplitude at 700Hz. The I-Q balance trimmer potentiometer should be
adjusted for minimum measured amplitude. This process is described in the earlier section
“Adjustment and alignment” at the end of the assembly part of the manual.
Содержание QCX 5W CW
Страница 9: ...QCX assembly Rev 1 08 9...
Страница 10: ...QCX assembly Rev 1 08 10...
Страница 12: ...QCX assembly Rev 1 08 12...
Страница 26: ...QCX assembly Rev 1 08 26 3 19 Install 20MHz crystal XTAL1 The engraving on this crystal is 20 000...
Страница 50: ...QCX assembly Rev 1 08 50...
Страница 105: ...QCX assembly Rev 1 08 105...