Hammo Can

[Kg7hyo]

 

Within the last few months I’ve seen a retail offering called the hammo can popping up in my facebook newsfeed. The idea is a weatherproof (when not in use) modular go-box that contains a mobile radio and a power source. They include a 5-12 amp hour AGM battery, small panel with 12V aux port, and what looks to be a 25 watt jetstream dual band radio all mounted conveniently in an ammo can. I was very intrigued by the idea, but when I saw a price tag of $350 + I decided I would build my own.

Here is what I did.

I bought a surplus 50 mm ammo can from Smith and Edwards in Northern Utah for $12.99 – Dimensions on the 50mm can are roughly 11″ long x 5.5″ wide and 6.5″ deep. Plenty of room for a mini-mobile radio but I would rather have extra room for extra pigtail cables, roll-up slim jim antenna, and extra batteries than possibly not enough room by using the smaller 30mm can.

I bought a QYT KT-8900 Radio off alibaba (Chinese direct shopping app). I actually bought two radios with programming cables for $130 shipped. They are 25 watt dual band radio’s that have largely positive reviews. They do have a few drawbacks. 1 – low power is only 5 watts under full power. 2 – Some report there is a strong picket fencing effect when mounted mobile in a vehicle (although I haven’t experienced this. 3- there is no audio out port.  These radio’s use the same kenwood mic pinout so it is possible to turn them into a cross band repeater using two radios and a patch cable between radios (info on making the cable available on the b-tech website).

I bought a combination panel mount setup off alibaba for $6 that included a voltmeter, 12V Aux Port, and a dual USB plug (1amp and 2.1amp).

I decided to use 12V portable lithium jump pack batteries, because they are already housed in a rugged case, much lighter and smaller than AGM batteries, relatively inexpensive (12 amp hour units have cost me between 25 and 35 on sale on amazon and alibaba) and because I already had 4 of them. All of the different jump pack batteries I own use a EC5 connector to get power to the jump leads, so I bought EC5 connectors from alibaba for about 56 cents shipped from china.

Here are links to a picture (because I’m struggling to link it to show up here in the thread.

http://s1043.photobucket.com/user/Sawyersneverlie/media/14484742_10154447935194713_7216478379479171488_n_zpsrrnb7x05.jpg.html

I am really happy with how it turned out.
My total investment is roughly $100 when I include some wire and hardware and a switch that I already had laying around.

Theoretically with some aluminum tape around the lid, the ammo can could serve as a EMP proof faraday cage and protect the self contained unit.
I am using a tram 1185 mag mount antenna because I think it works well and I already had it.  I will note that just sticking the antenna to the top of the box doesn’t work as well as sticking the mag mount to the removed lid and setting it on top. I assume this creates a better ground plane.

I included pigtails to power the box by the batteries (EC5 connector) 12V Aux Cigarette lighter connector, alligator clips to attach directly to a battery, and Anderson Powerpole connectors.

For a reasonable investment I think it will serve to be a very useful tool in my radio communications.

I’ve used the other KT-8900 in my work van the last two days and have to say, for $65 I am very impressed. Cheap enough I can have a dual band mobile radio in each of my vehicles now instead of just keeping a $25 Baofeng in each glovebox. Obviously it doesn’t compare to my TYT 8900 50 watt quad band mobile, or better yet the Yaesu FTM-400xdr or Kenwood TM-D710 radios our ARES team uses at mobile command or county EOC’s; but if it weren’t for cheap chinese radios I would have never been able to get into HAM.

 

 

• This topic was modified 8 years, 3 months ago by Kg7hyo.
• This topic was modified 8 years, 3 months ago by ldsadmin.

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[aranius]

This is really cool! I think I heard you talking about this on the Weber Co Ares Net last night! I am also trying to build one, although, I will probably get a bit more powerful radio… but its pretty minimalist nonetheless! Thanks for the inspiration.

[Author]

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