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Cluster Activity

Spots per uW band today:
UK spotter or spotted only.

Solar data:
SFI
67
A-Index
11
K-Index
4
Exp.K
0
Sunspots
15
Activity
qui
GMF
act
Aurora?
no

My Weather

Date:01/01/70 Time:01:00
Temp:C
Wind Speed:0mph
Wind Dir:deg
Pressure:0mB
Humidity:%
Dew Point:-20C
UKHASnet
77GHz Doppler Module - Part2

Here's a short update on the progress with this module.

I re-visited the 76GHz project the last 2 weeks and decided that having a larger antenna would be useful, the pcb antenna at somewhere around 20dB gain was not quite enough.
I ended up removing the pcb antenna to gain access to the wave-guide ports:

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The wave-guide ports had cutouts for the pcb launch so i had to mill of the face to get a flat surface to mate with, i then built an adapter plate to present something resembling a regular flange connection for connecting to another antenna. This gives access to two of the many ports available, i picked these based on the length of the RF path to the LNA/PA.

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Measured power is around 7dBm, 5mW.
RX Noise figure maybe around 15dB but i did not have the baseband output wired up correctly to check accurately.
The baseband output is very low so i will need to build some extra gain stage for Rx.

In the process of doing these tests/modifications i managed to damage the 19GHz VCO IC on the unit!!, the new arrangement is not ideal but has better phase noise performance and smaller frequency step than the original.

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The VCO RF path is like this:
ADF5355 at ~9.5GHz - LNB PCB Amplifier from -9dBm to +8dBm - LNB PCB doubler to 19Ghz at 5dBm
















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