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05/18/2011

I have been in the process of building a communications box to allow portable long range an local communications. This is not my Idea, and has been done many times before but my design draws from previous design and enhances upon it to suit my needs.

I wanted a box that was self contained, where I could switch from battery power source, A/C power in a matter of seconds, could be deployed quickly, and be semi water proof. I wanted provisions to be able to charge the batteries if electricity is up and also use solar power to charge it. I also wanted to have a way to monitor battery/ Power supply voltage and have a port for charging accessories, portable radio's.

I used a box that others have been using, it is made by MTM and called the SPUD-7. It has ample room and reasonable priced and fits the bill nice. Many others have mounted the radio and accessories to the box, and used rubber washers to maintain water resistance. I decided that I would rather have a rack that can be deployed out of the box at base camp, and allow for more air flow if needed.

I wanted to be able to use this at home, in the field, throw into the back seat of the car and operate mobile if need be. Since the face of the radio comes off, I already have a mount and cable run. I can throw it into the back seat, pull the face off, and clip it into the mount, and operate the radio while mobile.

Here is the box as it sits today, far from done but getting close.

Got the meter yesterday from China, picked it up and cut the hole for it. Got to test the box portable, and mobile and all worked as planned. The transition of sitting on the desk to being deployed in the vehicle was very fast and organized.

Now that I have the measurements of the meter I am going to order the panel so I can call "The Box" complete and move on to the other parts of this project.
 

07/14/2011

I posted pictures of my box build previously, far from done at the time but it was functional. Due to the size of the tuner I had I decided to omit the battery and put those in a separate box for the time being. I used a rack for my box giving me the ability to pull the rack out for air flow, and ease of service. I sold the Icom tuner and picked up an SGC 239. Freeing up the room to add the battery, and then I started to think how I could do things better...........

So I decided to lower the rack and mount the radio on the top, doing this would free up space on the sides to better mount the radio and power supply in a more uniform fashion. It also allowed me to mount additional items under the rack, and if I remove the rack from the box the speaker is no longer blocked.

I added my 17ah SLA battery where the tuner once was. Since I am running the Icom 706, the max power on 2 meter is 10 watts. Lowering the rack allowed me to mount one of my 2 meter amplifiers under the radio. It is an RF Concepts 2-30 amp, rated for 2 watts in 30 out. This amplifier produces about 50 watts on the power supply and around 40 on battery power.

I was going to order a custom machined switch panel for the box since I was unable to find aluminum plates that fit my specifications. Today I met up with Juan at his shop. He was able to find me a piece of aluminum that was 1/16 of an inch thick, and was formed at a 90 degree angle. The large size is 3 1/4 in, the short size about 1 inch, powder coated tan, Perfect for the switch panel! So I spent the last couple of hours cutting, drilling and filing. I am using the cigarette lighter adapter for the amplifier at the moment, I ran out of power poles fittings to tie the amplifier into the radio power wire.

I am still not done, I should receive my Icom to SGC interface tomorrow and will mount it up. The interface will allow the SGC tuner to be controlled and powered through the factory Icom AH-4, but much more range at a better price. I need to get a battery tender trickle charger and mount in it, and build a mount for the battery. I am going to make a small panel to mount under the power supply, it will have a 4 prong mic connector that will be used for the tuner control and power line, and a panel mount jack for a strait key.

The small reciprocating saw I used to cut the holes in the panel tore the powder coating up really bad. I decided to take the paint off with a whiz wheel a and debate if I was going to paint it. It created a swirl look on the aluminum and gave it sort of an industrial look, I decided I would leave it like that.

07/15/2011

SGC Antenna Tuner arrived today, Here is my portable antenna.

Ihave the line reels wound with 51 feet each of 22 gauge wire, i also have 28 feet of 300 ohm twinlead. That gives me a 102 feet antenna that will fit into a cargo pocket on a set of pants! I have a Pelican 1200 case on the way to mount the SGC 239 in. I will use an N connector bulkhead for the Input and a 4 Prong Mic connector for the control and power wire for the tuner. The output will be Binding post/Banana plugs, this will allow me to feed the antenna in a doublet configuration, making a portable G5RV, or I can plug the reels into the pelican case to run any number of antenna configurations using a random wire and counterpoise. Of course they will be water proofed and test for integrity.

The pelican 1200 should have enough room to store the portable antenna when not in use. I will post updated pictures when I get the SGC box mounted and wired up.

I also used my additional 17 AH batter to make a Auxiliary power station/Jump Box from a plastic ammo can and a bunch of stuff in my parts junk drawer. I am waiting on the Powerpoles to get here and I will post pictures of that as well. It will serve as a multi purpose power station and will have some very neat accessories to power many things.

I am also going to add one additional solar panel for about 3 watts output, or around 250ma of charging current.

I will post updates as I complete them.

Today I got the second panel mounted, I had to take the cig lighter adapter out to make room, but that is ok I have a different one that I will put some power poles on. I cut the panel shorter to make room for the Signallink USB that will be coming in another week. I added some of adapters I had laying around that will allow me to connect a CW Key, a CI-V cable for rig control and I will have a USB "B" panel mount coming in to connect into the signal link. It will allow all the connection connected through the panel.

I mounted the tuner controller to the side of the amplifier using Velcro, I will need to come up with a different mounting solution, once it gets hot the adhesive is likely to come off. I was going to mount it to the right of amplifier, but needed to make room for the signal link. According to the specs I should have enough room, I have exactly 3.75" between the amplifier and the right side upper panel.

I also cut the aluminum tuber down to fit over the all-thread that I am using for rack standoffs, I originally used the tubing but did not get around to cutting it down and installing it. I was also able to make a hold down for the battery out of 1" aluminum straps bent to fit over the battery and held down with bolts through the bottom rack.
 

07/17/2011

Received the tuner control interface yesterday. Thanks to one of the AR15.com Hams that told me about the Icom/SGC tuner interface controllers from http://www.ham-kits.com/mainframe.htm. The interface allows the Icom radio to control the SGC tuner through the radio just like the Icom AH3/AH4 tuner. It powers the tuner and interface from the radio, and also has a hold switch that allows you to lock the current tune in, that way a changing antenna environment with varying SWR will not go into tune mode in the middle of the QSO.

It also has a Fault LED telling you if the tuner was unable to tune, or if it is in bypass mode. It is a very nice kit, and this is what it looks like fresh out of the package.

 I cut another plate for the box, this will have the microphone connector that will lock into the box just above the BNC connectors. The cable I used to run to the tuner box is 4 wire ribbon cable that is used for trailer wiring. I will be using a 25 foot run of it, heat shrink to the RG-58 coax cable. It will run to the Pelican 1200 case containing the SGC tuner. I plan on using some braided wire sleeve in OD green to cover the coax and ribbon cable. Here is the Panel and the wiring I will be using.

I hooked the ribbon cable directly the the tuner and tested it out tonight, the interface works great! One push of the tuner button on the radio it switches to CW mode and sends a tone, the tuner relays lock in the correct setting and switches back to the SSB mode. The Icom radio also has a setting that will enables the tuning the first time the PTT button is pressed when you switch bands or change frequency more than 1%.

I will update when the tuner box shows up and the panel is mounted in.

07/20/2011

Today I got the second panel mounted, I had to take the cig lighter adapter out to make room, but that is ok I have a different one that I will put some power poles on. I cut the panel shorter to make room for the Signallink USB that will be coming in another week. I added some of adapters I had laying around that will allow me to connect a CW Key, a CI-V cable for rig control and I will have a USB "B" panel mount coming in to connect into the signal link. It will allow all the connection connected through the panel.

I mounted the tuner controller to the side of the amplifier using Velcro, I will need to come up with a different mounting solution, once it gets hot the adhesive is likely to come off. I was going to mount it to the right of amplifier, but needed to make room for the signal link. According to the specs I should have enough room, I have exactly 3.75" between the amplifier and the right side upper panel.

I also cut the aluminum tuber down to fit over the all-thread that I am using for rack standoffs, I originally used the tubing but did not get around to cutting it down and installing it. I was also able to make a hold down for the battery out of 1" aluminum straps bent to fit over the battery and held down with bolts through the bottom rack.

07/21/2011

Ok today the pelican case came in! I made a run to the local electronics store to get some supplies to put this thing together. I still need to weather seal the Mic plug and the binding post. The N bulkhead connector has an O-Ring seal. I used adhesive Velcro to secure the tuner to the bottom of the pelican case. I need to get some desiccant to add to the case, it gets a little humid here.

Here is some of the pictures, let me tell you it felt wrong to pull that pelican case out of the box and drill holes in it!

And here is the rig put together. I have since built a PSK interface and CI-V controller. I may pickup a Signal Link to mount into the box, for portable operations. But for now, I am enjoying using a completely homebrew interface, and feel that making your own stuff is the spirit of ham radio.

As it sits here is a parts list for the box,