QCX assembly Rev 1.08
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8.1 Align frq
14,020,000
The Align frq. parameter specifies the frequency which the alignment tools operate. You should
ensure that the frequency specified is in the centre of the CW section of the band of operation of
your radio.
8.2 I-Q bal frq
700
The audio frequency at which the I-Q balance adjustment is performed. By default this is set to
700Hz, the centre of the audio filter and what is usually used for the CW offset frequency.
8.3 Phase Lo frq
600
The audio frequency at which the LOW audio frequency 90-degree phase shift is performed.
8.4 Phase Hi frq
800
The audio frequency at which the HIGH audio frequency 90-degree phase shift is performed.
8.5 Ref frq
27,004,000
The reference frequency for the Si5351A synthesiser chip. If you set this to the actual oscillation
frequency of the 27MHz crystal, then the output frequency of the radio will be accurate.
Usually the 27MHz crystals oscillate between 3 to 5kHz too high. This is the reason for the default
setting of 27.004MHz (4kHz high).
You can measure the 27MHz reference value yourself if you have a reliable general coverage
receiver whose frequency is known to be accurate. There are other methods too! You could set
the signal generator to a certain frequency such as 10MHz. Then beat it against a 10MHz
reference, for example. Measurement of the audio offset would enable a calculation of what the
correct 27MHz reference value ought to be.
Содержание QCX 5W CW
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