IC-9700
Było rozwiązanie błędu dryfu i blokowania oscylatora przez GPSDO na 23cm:


An additional report has been added to the Drop box below relating to the drift when the fan is run continuously.

https://drive.google.com/open?id=1OSha3iKWcl5q2IiJjXcPIXC_fUd1DYAL

In summary running the fan continuously makes the radio viable for most weak signal modes, if you are in stable temperature environment such as an air-conditioned home. There are downsides in that:

· The fan may fail prematurely.
· There is more fan noise
· The radio is more sensitive to external temperature variations.

This approach has an advantage over the Zener Diode mod which results in the fan speed varying from RX to TX and introduces around 7 Hz variation at 1296 MHz between TX and RX.

While this approach makes the radio viable I see this as a work-around rather than a solution. I consider GPSDO locking is still required for serious weak signal operations - in particular for field operations where the radio can be exposed to sharp temperature changes such as the sun shining on or off the radio.

The good news is that VK1XX has been able to GPSDO lock the IC-9700 with very promising results. This does require a board to be added along the lines of the VK3HZ units for the IC-9100 and some difficult soldering. I expect to have a GPSDO locked radio by the end of this coming week and will report further to the group.

73 Rex VK7MO


Lepiej byłoby wydać IC-9710 :-D

73, Drahos OK2DTF/DK2DTF


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