40m band is poor today and I want to listen to the AM broadcast band. However, my IC-M700TY HF transceiver can only go down to 2MHz. Upon checking my junk box, I found the right components to assemble an up converter so that I can still hear AM broadcasts on my transceiver.
The illustration above depicts a diode ring mixer, In my prototype, I am utilizing four closely matched 1N4148 diodes based on their forward voltage and a pair of FT37-43 toroids as a core for my broadband transformer. The transformer is wound with four trifilar turns of #22 AWG insulated wire.
I've enclosed the finished prototype in a plastic container and I've installed a pair of connectors on the side for easy connection of the aerial antenna and the patch cable leading to the antenna connector of my IC-M700TY. The aerial antenna will be connected to the RF port while the baseband output signal can be extracted from the IF port of the ring mixer.
To make this set-up operational, the AM broadcast frequencies will be present at both (10MHz + AM band) and at (10MHz - AM band). For instance, if DZMM is broadcasting at 630KHz, it can be received either at 10.630MHz or at 9.370MHz ---73 de du1vss
