Frequency doublers from 12GHz to 24GHz with (at least) 10mW or 100mW output power:

I noticed this parts at the Hamradio Friedrichshafen in 2018. They have a SMA input and a WR42 waveguide output. I put here some screenshots of the input spectrum (Gigatronics 1026) and the output spectrum of each type, measured with an Anritsu MS710C, a high-quality WR42/SMA adapter and the help of the 7470 emulator of KE5FX. As power supply I used a Keithley 2231A-30-3. Voltages are partly written on the parts, partly I had to "guess" and look for some limits where it looks to work stable.
Here is some key data I was able to acquire:
  • Works well in the 1.2cm amateur radio band (e.g. in: 12024MHz, out: 24048MHz).
  • The 10dBm output type requries only two voltages (9V and 5V seems to be ok, ~180mA each).
  • The 20dBm output type requries three voltages (12V/~60mA, 5.7V/~250mA, -5V/~4mA).
  • The input power (saturating the output power) is around 0dBm for both types (a bit more seems to be still ok).
  • The higher harmonics are surprisingly low, if I didn't make a mistake. Need to re-check another time later on...

NORT microwave PLL block:

The PLL is enclosed in a small aluminum case with an SMA output connector on one side and a 6 pin SPOX connector on the other side. Originally designed for ~13 GHz, the internal discrete VCO at ~3GHz (quadrupled and amplified) can be tuned for other center frequencies as well. It uses an ADF4153 connected to a 20MHz TCXO which can be trimmed through a small hole on the back side of the casing (you can see the hole in the middle of the case in above picture).
Using my code from my ADF4153 Master setup for Arduino, the output can be controlled in steps of 10kHz (the original datasheet claims 250kHz steps only, but they probably did not have any other requirement for more closer step sizes for their original application).
The first picture above shows the internal PCB after opening and the second picture shows the module connected to an ESP12 module to allow frequency control using a WiFi interface. This is quite convinient when I use the module as simple beacon I can put somewhere in my garden together with a small battery for some basic antenna tests on 3cm. As the ESP12 development setup is not so trivial, I do not want to release it. Experienced programmers can just take the code from the Arduino project, which is basically the same, and adapt it for the SPI interface.
I implemented a very small PCB which should fit in the casing and allows programming via the existing SPOX connector using a standard FTDI (original FT232RL, no China replica) USB controller for a few Euro.
The picture shows the PCB as image pasted into a photograph of the bottom side of the casing where the TCXO resides. The trimming hole will be still available.
The control-PCB is finished!
You can find details about the project here! As you can see, you then just need a voltage supply to operate the module:


...more to come!

  • 28GHz full-duplex transverters
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