You simply repeat all steps for the 80m band. Only this time in the 10m band and using
the TX IQ Balance/Phase 10m settings. The initial USB frequency should be 28.124.000
Mhz (Receive for monitoring original TX signal is LSB: 28.125.500, USB: 28.124.000). The
second receiver's LSB (!!) frequency for calibration purposes is 28.100.000 khz. A
spectrum analyzer or IQ receiver will show the weak signal around 28.099.250 Hz.
CW TX 10m/80m calibration [from version 1.5.7]
1.
Set USB mode on mcHF. (Yes!)
2.
Set Frequency Translation to OFF
3.
Set LSB mode on second receiver.
4.
Set mcHF and second receiver to 80m: dial frequency 3624.00 kHz. Now minimize
received signal using CW TX IQ/Phase settings for 80m.
5.
Repeat the last step for dial frequency 28.124.00 kHz and minimize with CW TX
IQ/Phase settings for 10m.
6.
Restore original frequency translation mode.
Do NOT use CW for setting this because of the settings for frequency of second receiver
would differ. Why make it complicate if it can be done simply?
RX IQ Adjustments [Valid from 1.5.2]
There are two ways to adjust for IQ phase and amplitude imbalances in RX:
1.
Automatic IQ correction [Valid from 1.5.8]: Just go into the Configuration Menu
and switch "RX IQ AUTO CORRECTION" to ON. Ready to go! No more
adjustments required. This can achieve up to 65dB of mirror rejection! Thanks to
Yves HB9EWY for doing a real and reliable measurement! If you believe you can
do it better than 65dB with your hands on your mcHF, you will have to do the
manual IQ phase and amplitude imbalance adjustment:
2.
Manual IQ correction: You will need a signal generator for 80m and 10m. If you
use a normal transmitter with a tune signal, use
USB
mode on that transmitter.
Make sure you receive the strong main signal on the original RX frequency before
searching the weak signal on the secondary frequency!
Preparation RX Manual IQ correction
1.
Get the frequency translation to -12khz (after calibration you may set any value
you want)
