HF Mixer Module
This mixer module is intended for an HF receiver, and should be preceded by an appropriate filter for the band(s) of interest. A suitable pre-amplifier might be needed on the higher-frequency bands.
The mixer is quite straightforward - an MCL TUF-1 DBM followed by a post-mixer amplifier and resistive pad The post-mixer amplifier (taken from the ARRL Handbook of a few years ago) ensures that the mixer is properly terminated up to about three times the IF frequency and the gain makes up for the losses in the mixer. The resistive pad on the output ensures that the following crystal filter has a purely resistive input.
The PCB is double-sided with a ground plane on the top. It should be quite easy to make at home. A few wire links are required between the top and bottom layers.
Here is what the actual prototype I built looks like:
I subsequently changed the PCB slightly, making it a bit neater. A small heat sink on the transistor would be a good idea, as it gets a bit hot.
Artwork for the PCB is here
PCB designed with Pulsonix