Hi Ron, Jack and James.? 'Hambus' -- there's an idea.? Modules are common enough, Mark at Minikits has a complete HF transceiver with header connected modules, some (crystal filters, BPFs, LPFs) of which stack.? These hint at a bus, with consistent assignments of power, control and signal lines to specific pins.? Other projects have pluggable daughterboards (the venerable Sierra's neat band plugins, for example).??
The idea of a universal bus is appealing. In computer tradition, the Hambus could be standardised and managed as a product in its own right. Modules could then be designed for Hambus versions. Imagine mixing and matching homebrew and vendor modules on a Hambus.? Layout would be important for screening and short paths, but? James' suggested 20 double 0.1 headers should be enough separation.? Perhaps some strategically placed jumpers on certain bus lines (audio, RF) could trim signal bus lines for better isolation.?
First problem to solve -- how do you get physical strength when you edge mount a vertical board on a double row 0.1 header?? Slide the board between the two rows, bend pins in, solder both sides???
Minikits M1: https://www.minikits.com.au/m1-transceiver.htm
VK3HN