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You can't fix stupid
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Discussion Starter #1
Hello all. I have been wanting to assemble a ham radio go box for some time now. I have had the case for a while but need help determining just what parts I will need to buy to complete it.

Goals-relatively small/lightweight box for true emergency communications. I don't need a bunch of bells/whistles. It just needs to be functional and effective. Usable on battery power yet able to be plugged into a power outlet and used that way while charging the battery.

The radio I will be using is a quad band Yaesu FT-8900 (10m/6m/2m/70cm)
This radio only has one antenna output on the back. Instead of using a single quad band antenna which is a pretty big compromise, I would like to use 2 antennas. one for HF and one for VHF/UHF.

For handling power to the radio and charging the battery I have been looking at the Astron BB30M. It's small, lightweight, from a reputable company and not too expensive. Is their a better option for this component?

I have not decided on just what battery to use. I would want it mounted under the deck in the case so it can be all in one self contained. Having the ability to connect jumpers from the case to a car battery would be a plus.

Most Go Boxes have a rigrunner for easy wiring of the radio. I am planning on including this or a like item from another company. Having the ability to charge a device through USB is also a plus for me so I would get one with at least one USB.

I will be mounting a computer case fan to exhaust the warm air created by the components.

I like the idea of having an extendable metal VHF/UHF antenna mounted to the deck of the case because it uses such a short length of high loss coax. On the other hand I am not thrilled about having RF that close to my brain bucket when operating. The other option to this is a roll up dual band slim jim/J pole. For this I would use small diameter low loss cable like LMR-240.


Anything I'm missing. Open to all suggestions, thanks for any help.
 

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reluctant sinner
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That sounds like a good project. I'm going to use a Yaesu FT-2900 in a military ammo can, a big/tall 50 cal is my first choice. I'd like to make up a bank of 18650 batteries to power it. I'll do some sort collapsible pole that fits inside the can. Charging cord and the power pack will also be in can too - no openings in the can wall - so its a cage too.
 

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You can't fix stupid
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Discussion Starter #3
A quad band radio probably wouldn't have been my first choice but the radio is very small while still having a large display. It will be nice to have medium range HF capability from a portable radio. Plus, I got it for a great price.

Having looked at a lot of radio go boxes, I really like the design and simplicity of this one.
http://emergencyradiogokit.com/

My kit will be smaller and lighter. The orange case used in that link is a Pelican 1520 with interior dimensions of 18x13x7". Mine is a Pelican 1450 with interior dimensions of 15x10x6. Mine weights 5.5# empty vs the 1520 which is 8.5# empty.
 

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reluctant sinner
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My metal can is about that size. It will be attached to the rack on my 4 wheeler, so outside durable is high on my list.
 

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Not sure what your use case is, but antennas inside commercial buildings leave a lot to be desired. So I’d plan on running to a mag mount outside, or a ground plane. You can buy ground plane kits for a NMO whip, or several companies make a ground plane antenna where there is a center piece tapped for 4 radials and one radiator.

Probally also handy if you can feed power to a second rig or LTE modem.
 

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You can't fix stupid
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Discussion Starter #6
If using it inside it would be inside a residence, not inside a metal framed commercial building.

I had considered a mag mount as I have one now but that means I would need to lug around a chunk of metal for the "other half" of the antenna. At home I was actually getting good output sticking my mag mount to my 4 drawer steel file cabinet!

I like the mobile type antennas but I would want one that is easily collapsible which I am having trouble finding. Because of this I may just buy a dual band slim jim antenna then build a simple fan dipole for 6m/10m. I know it's not ideal but portability is the priority.
 

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Stop YOLOing
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Just finished building this today. I wanted more modular and mobile, choosing to sacrifice the durability of a hard shell or box. It's based on a Condor Pack Insert that has everything I need to stick into any backpack, vehicle, or onto tabletop and talk to folks (except the antenna because that's tailored to the task, but I have a few to choose from).

Parts list is at the link. It's a pic-heavy page, so beware if you're on a slow connection.

http://www.tothewoods.net/Comms-Yaesu-817-818-Manpack-Mobile-QRP-Ham-Radio-Kit.php



 

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Retired *****
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That sounds like a good project. I'm going to use a Yaesu FT-2900 in a military ammo can, a big/tall 50 cal is my first choice. I'd like to make up a bank of 18650 batteries to power it. I'll do some sort collapsible pole that fits inside the can. Charging cord and the power pack will also be in can too - no openings in the can wall - so its a cage too.
I have a FT-8900. 6 meters and 10 meters FM isn't really HF so there's that.

As far as a battery while you are considering making your own, have a look at LiFePO4 batteries. Expensive for small amp-hour capacity.

  • 1/3 – 1/5 the size (and weight) of a comparable lead-acid battery in a given application
  • Up to 5 times the service life of a comparable lead-acid battery in a given application
  • Very fast recharge rate – they can recharge to up to 80% of their full capacity in only minutes
  • Very low self-discharge rate – they only lose about 10% of their charge per year when sitting, compared to lead-acids which will lose about 1% of their charge per day
  • Ultimate deep discharge battery, compared to lead acids that are “dead” at 70-80% charge
  • Higher CCAs when compared to a lead-acid battery for a given application (usually about 1.5X)
  • Safer because they use a completely dry chemistry, compared to lead-acid batteries which use both hazardous lead and corrosive acid
  • Longer warranties than most lead-acid batteries

https://dakotalithium.com/product/dakota-lithium-12v-10ah-battery/?v=7516fd43adaa

The Yaesu FT-2900 draws 15 amps at high power so you will need a suitable power supply or a battery that can provide it.

https://www.universal-radio.com/catalog/fm_txvrs/2900spec.html
 

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reluctant sinner
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Those batteries do look interesting. I will need to investigate the charging requirements - I want to be able to use the limited system on my older Suzuki 4 wheeler and solar panels.

I like the 18650 size because I can use them in my head lamps and already have a car charger unit that will run on 12 V DC or 120 AC.
 

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Retired *****
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Those batteries do look interesting. I will need to investigate the charging requirements - I want to be able to use the limited system on my older Suzuki 4 wheeler and solar panels.

I like the 18650 size because I can use them in my head lamps and already have a car charger unit that will run on 12 V DC or 120 AC.
The problem that comes with building your own battery pack based on the 18650 cell is balancing the charge and discharge of the individual cells. Battery manufacturers have dedicated circuits to handle this. If you've ever torn apart an old laptop battery you will see this along with a heat sensor.

Gigaparts has a whole range of LiFePO4 batteries to choose from. So does Amazon.

https://www.gigaparts.com/nsearch/?...s&keywords=batteries&search_return=all&page=3

Your solar charge controller will need to be able to charge LiFePO4 chemistry.
 

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If it were me, I would be looking at an Yaesu FT-817nd or the 818nd, qrp rig. Add a solar trickle charger and you are set. 5w is plenty and it will listen VERY WELL on lower HF bands also. Would fit into a chest rig or small backpack.

If you want to up the power, get a couple of compact ATV 12v batteries (or compact 12v deep cycle batteries) a solar charger for trickle charging and a 50-call ammo can and Yaesu FT-857.
 

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You can't fix stupid
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Discussion Starter #13
If I choose to use a LiFePO4 battery to power the FT-8900, is their an all in one transfer switch/charger that is lithium compatible?
 

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reluctant sinner
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Retired *****
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If I choose to use a LiFePO4 battery to power the FT-8900, is their an all in one transfer switch/charger that is lithium compatible?
I'm not sure why you would need a transfer switch. Are you not running the radio off the battery all the time?

To charge the battery using solar, you would need a charge controller that is compatible with LiFePO4 batteries such as this one:

https://www.amazon.com/dp/B01BXRIRQC/ref=emc_b_5_t?th=1

6.8 x 1.7 x 5.5 inches

It will accept a maximum of 130 watts at 13 vdc from solar panels, but that should be enough for something packable.

Here's a folding solar panel set that puts out 6.7 amps at 13 vdc.

https://www.amazon.com/dp/B082W5HVG...pY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU&th=1

Folded size is 16" x 14"
 

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Retired *****
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On the subject of ham radio "go boxes".

I'm not sure I get the concept. Is the plan to walk wherever you are going or drive?

If you are walking, how will you deal with a normal backpack full of your necessities along with a radio go box?

If you are driving, all you need to do is mount a mobile radio in the vehicle with antenna and you are good to go.

Somebody please clarify.
 

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Stop YOLOing
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Retired *****
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So the purpose of the kit isn't to hike out into the woods and hole up for a while with all the stuff on your back needed to survive? To do that you would need a solar panel array to charge the battery.

I guess I'm looking for a scenario.

I do like the well thought out system you have though. :thumb:

====

How about something really quick and dirty like the 2m/440 Baofeng you already have, a Mirage BD-35 linear amplifier and a battery to run it. Many different antenna options.

Works with HTs to 7 Watts. Compact 5" W x 1 ½" H x 5" D. Draws 7 Amps at 13.8 VDC.
45/35 watts out with 5 watts in. Only use the amp when needed. $279

I get that you might want HF capabilities so there's that drawback.
 

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Stop YOLOing
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Adding a solar panel to this kit wouldn't be hard. It's good for backpacking and fun, but it's not the only thing I'd take if things got bad.

The purpose of this kit--and at least partly OP's, because he has 10m--is to have HF. 5W on HF has a longer range than 45W on VHF. And one of the main purposes for HF in a bad situation is collect intel...so transmit power doesn't matter.

But I made my kit modular so it fits my 25W UV-25X4 as well, in case I need more VHF/UHF power.
 
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