Since the start, I have taken a loop construction modular approach which makes it easy to experiment with different ideas.
Using clamps, screw terminals and breakout boards might not be as pretty as unified construction. But I have learned over the years it provides a lot of flexibility and forgiveness. Two of my favorite tools are screw terminals and RJ45 breakouts.
To provide input and output to circuit boards, I have standardized on two and four pole screw terminals. These are universal terminal blocks with 5.08 mm pitch, easy to solder onto PCB. Each will handle signals or power connections. You can buy these all over the place and they are quite low cost. I usually tin stranded wire first and find the connections are almost as good as soldering.
For working with CAT cable, I bought a whole bunch of female RJ45-to-screw-terminal breakout modules. These cost around $3 each. You will find they work perfectly for connecting twisted pair CAT cable to PCB. Each module breaks out the four pairs in CAT cabling. Unfortunately, they will not pass through the shielding if you are using shielded cable. But you have tremendous flexibility in wiring the cables to your modules.
If you are attaching CAT cable to a plastic enclosure, like with my 3D printing, it is easy to size holes and make a solid connection with these modules. A bit of silicon will provide water-proofing and extra strength.
Finally, if you are looking for an easy way to connect copper wires to an aluminum tube, Micro-Gear hose clamps from Ideal-Tridon do the trick. Available in sizes down to less than a half-inch, these are easy to work with. With a bit of torque, you can create a solid compression connection between copper and aluminum, which cannot be soldered together. You can find these or their equivalents at most hardware stores.
Loop Construction Modular Approach – Take a Look
In the picture above, you can see Micro-Gear clamps holding loops of #14 wire to aluminum core PEX. This provides a good connection for the LZ1AQ amplifier input.
On the right, the picture shows power and signal output connections to CAT cable through the RJ45 breakout module. Screw terminals are soldered to the input, output and power leads on the LZ1AQ amplifier PCB.
With this loop construction modular approach, I can easily try different loops, amplifiers and systems with the twist of some screws. Good fun!