My poor FT-857 has had a rough life. It’s been used portable and usually ends up being thrown in a bag with the ATU, battery and other parts. I decided it was time to show it some respect and create a military inspired manpack to keep it safe and secure.
After searching youtube for some ideas, I settled on making a sort of exoskeleton frame to fit the FT-857, LDG Z-11Pro 11 and battery inside. I decided to make the basic frame from 15mm copper water pipe because I had a few sections laying around and just needed a few fittings. I also wanted my manpack to be contained inside a backpack for protection and easy of transport. I like to operate on HF from the local beach so having something that I could just throw on my back an go is also a bonus.
Keeping with the military theme, a visit to the local surplus store yielded a suitable backpack with a single large pocket and 2 smaller side pockets. It also has some molle loops to I can easily add additional pockets if needed.
I measured the internal dimensions of the main pocket and used AutoCAD to design a frame to fit inside. I decided to make the frame from 15mm copper water pipe as I had some spare and just needed a few simple fittings.
After checking that the FT-857, LDG Z11Pro11 Tuner and battery would fit inside, I cut the copper pipe and started to assemble.
Once the frame was dry assembled I tested the equipment for fit before soldering the frame together using a blow torch.
Soldering the frame was easy but I wish I had used the type of connectors that are not pre soldered. The ones I used had a ring of solder inside the connector so I had to make sure each connector had the correct tube inserted before I applied heat.
A quick test fit in the pack to make sure it fitted.
With the basic frame done, I cleaned it up and started to add the fittings. First, some aluminium strips to support the battery. I tried to solder the strips to the copper but it was very messy so I ended up using some small rivets instead.
Next up was the strips and bracket to support the FT-857.
Followed by the antenna connection brackets and ATU support.
I cleaned the frame again and rubbed it down with wire wool before giving it a coat of paint. I used some “truck bed” paint from the local auto store which was billed as “hard wearing” and leaves a textured (think sandpaper!) finish.
I wanted to soften the frame up a little and protect the paintwork on the base and handles so I found some DPM bandage (originally for my dogs injured leg) and used it to wrap parts of the frame. It’s a bit spongy and makes the handles a bit more comfortable.
The LDG tuner was attached to the frame with some double sided foam tape. This stuff is used in cars to fix trim and is very sticky!
Next to go in was the FT-857. It sits in the original mobile mounting bracket with the microphone clip attached via a bracket screw.
Last to go in was the battery. I use a 7Ah 12v SLA battery and usually run the radio at 20W or less. The battery is held in place with a webbing strap (I need to get a black or green one to replace the orange one!) and connects via powerpole connectors for easy charging.
The frame slips in and out of the pack very easily and can be use in or out of the pack. Here it is complete with a dual band 2M/70cm whip fitted on the right and a 4M long MOD surplus vertical fitted on the left (running through the ATU).
I intend on adding extras as I get used to using the pack and hope to end up with a complete station in a simple to carry and robust package.