Another successful 3D printed gadget for the radio room. This time, I built an accessory power distribution box for a couple of dollars.
Recently, I described my efforts to get rid of switched mode power supplies for accessories in the radio room. My plan was to replace six wall-wart SMPS with a 12 VDC linear regulated supply. Turns out that I found four of these linear power supplies collected over the years and just sitting around. Each of these has more than enough juice to run five or six different accessories (antenna relays, noise cancellers, etc.)
But I did not want to run power cables from each accessory to the power supply. So, I 3D printed an accessory power distribution box, shown above. All of the parts needed, mainly colored binding posts, are readily available online.
My intention was to mount the box near the accessories, and then run one main cable to the power supply. You can see that the accessory power distribution box has three sets of binding posts, as well as a barrel connector, all in parallel. The idea was to feed power to two devices from each set of binding posts.
Also, I spaced the posts so that a dual tipped banana plug could fit in easily, as well. If more posts were needed, a couple of these units could be daisy-chained together.
Keep in mind we are talking low voltage and low current here. Also, for protection, the linear power supply is fused.
Radio Accessory Power Distribution Box – Tips
When you use flexible stranded wire for power (and you should) most people use a spade or ring terminal lug to attach each wire to the post. Here are some things to keep in mind.
Most cheaper binding posts only have enough travel to connect and tighten down one or two wires. You should check dimensions so you know what you are able to do. I discovered this the hard way.
Terminal lugs come in different dimensions. First, the inner diameter of the lug must be large enough to fit the binding post. Second, the lug should be sized for your AWG wire size. Lugs for smaller dimension wires like #20 or #22 are a bit harder to find.
Oh yes! Make sure that positive and negative rails are clearly marked and cannot short!