Radio Cage

clee 4U synth DIY Yusynth transistor ladder filter 

The Radio Cage is a voltage controlled radio reciever patched through a VCA/Ring Modulator and a Voltage Controlled Filter. The module also has a Voltage Controlled LFO.

The radio (mono) recieves AM, FM and Shortwave bands in both US and international frequencies.

The radio, VCA, and VCF can also each be used independently: A radio direct out is available. By turning the radio volume down and using the EXT IN the VCA/VCF is independent, and by using RADIO BYPASS the VCA and VCF are unpatched. Then using the filter EXT IN the VCF can be used by its self, patching from one of the 3 VCF outputs and the VCA out is available at the main output. This also allows you to change the order of the patch to Radio -> VCF ->VCA.

BlockDiag 

Build notes

stackboardsSeperatepanelbackFilled 

Construction is a panel PCB and a component PCB

Some resistors and a capacitor are on the panel PCB

The banana jack holes are plated but are not an electrical connection. Solder small wires to the trace pads from the jacks

IMPORTANT: The module needs to run on +/-12V. The AS3360 VCA chip can't be powered by -15V

Current build is Version 1.0

Download the schematic here: Radio Cage schematic

Download the BOM:Radio Cage BOM

Download part placement: Radio Cage part placement

Download trimming Instructions: Trimming

The module uses the Skyworks Si4825 chip for the radio. Here's the datasheet for the chip if you'd like more information

Notes

antennaantennaConnect 

AM Antenna :
The antenna can be mounted internally if your enclosure allows it to work without interference. Space is provided on the component PCB for the antenna. In the prototype build I created footings with hot glue and cable tied the antenna to the board

Otherwise connect the AM antenna by stereo 1/8" jack

antennaConnect1 

Instal capacitor laying down :
The capacitor on the panel PCB should lay down so it fits between boards

antennaConnect2 

Band Switch :
The band switch needs to be fly-wire connected.