QRP Labs QCX 5W CW, Руководство по сборке

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QCX assembly Rev 1.08
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7.7 S-meter step
100
This NUMBER parameter effectively defines the sensitivity of the S-meter. The S meter has 12
bars maximum. Each bar of the S-
meter equates to the specified “S-meter step” number on the
amplitude measurement scale. So, in this case the scale of the 12 bars of the S-meter will mean 0
to 1200 in amplitude measurement terms.
A lower S-meter step number makes the S-meter more sensitive; a higher number makes it LESS
sensitive.
The S-meter reading is indicative only, it does not have any highly accurate meaning. In any case
the audio sampled by the Analogue to Digital converter is after the audio amplifier gain stages so
the amplitude depends on the receiver gain setting.
7.8 Factory rst.
Sure? enter 17
This menu item can be used to cause a factory reset. Factory reset returns you radio to the
supplied default factory configuration. Everything is erased and set back to the default parameter
values.
In order to prevent accidentally triggering this drastic step, the factory reset is implemented as a
virtual 2-digit numeric parameter. To cause a reset:
•
Press the left (“select”) button to start editing this menu item. 00 is displayed
•
Use the rotary encoder to change the value to 17
•
Press the left (“select”) or right (“back”) buttons to enter the value 17, which causes the
factory reset
Factory reset takes a few seconds while the entire EEPROM contents are written. After the factory
reset you will see the “Select band” prompt again, the same as when you first power up the radio.
4.26 Alignment menu
The alignment menu contains several tools for alignment and calibration of the radio, using the
built-
in signal generator to inject a test signal back into the receiver’s front end.
Correct use of these alignment tools makes it possible to adjust and align the receiver without any
external test equipment at all.
Please also refer to the alignment/adjustment section at the end of the assembly part of the
manual, which describes how to use these tools to peak the Band Pass Filter response, and to
minimise the unwanted sideband using the I-Q balance and audio phase shift adjustments.