In my last two blog postings I discussed suggestions and ideas for what might make the best radio and antenna setup for a typical SOTA activation. In both articles (as is also the case for all content on this blog) I share my opinions. As is the case with most things in life, alternative methods and solutions exist. My goal for this blog and these “how to” articles is to provide an honest opinion on what has (and even what hasn’t worked) for me.
Once you figure out what type of radio and antenna you will use, the next important item to consider is portable power. If you are opting for a V/UHF SOTA activation and only plan to pack along a hand-held transceiver, then the battery pack which comes with the transceiver should work fine. It may also be helpful to have another battery pack or two for extended operations. Most all hand-held transceivers will have an accessory option to purchase additional battery packs. Some manufactures offer a pack option which will accept AA batteries.
If you have decided to operate HF (or packing along a mobile V/UHF transceiver) you are going to need portable power. How much power you pack along will really depend on how long you plan to operate and how much output power you plan to run. Remember, QRP power levels at altitude works well in most situations. Said in another way, you don’t need to run 100 watts of power when you are standing on top of the world.
Now if you have operated portable (picnic table portable) perhaps you have used a deep cycle marine battery or even a typical 12v car battery. Both work well when you only need to carry them a few yards from the car to the picnic table. However, these options just aren’t practical for SOTA. The good news is we have a lot of options for 12v power without breaking our back carrying around a heavy car battery.
Sealed Lead Acid/AGM/Gel-Cell Types
I’ve used these types of batteries for many of my portable and even SOTA activation operations. There are both advantages and disadvantages to these types of batteries. Cost certainly is an advantage. I’ve found the 12v 7.5 Ah batteries available for under $25 USD. The weight of the battery is a slight disadvantage, another important disadvantage is the overall output life of the battery.
A123 Nanophosphate Technology
The semi new nanophosphate battery technology is impressive. If you’ve looked at my SOTA Gear List, you’ll see that I use an A123 battery pack from the Buddipole company. I won’t lie to you, the cost of these packs may certainly be viewed as a disadvantage. But my opinion is the advantages far make up for the investment.
I own the large 4S4P model (10.0 Ah). If I had to do it over again, I would have purchased two of the 4S2P (5.0 Ah) or two of the 4S3P (7.5 Ah) models. This would have provided more flexibility on hiking and camping trips. Or would have allowed for one pack to charge while using the other.
Final comment about the A123 packs. Unlike a traditional SLA or AGM type battery which may start off providing 13.2 volts then slowly begins to decrease as you use the battery…the A123 packs deliver a constant and steady 13.2 volts throughout the use.
Other options to consider
There are some lightweight options which might be worth considering. In our cars the most important dashboard gauge is the gas gauge. This important indicator tells us how much fuel we have and a general idea of how many miles we can drive before we end up walking. I highly recommend using a lightweight in-line meter like the Doc Wattson Meter.
What about Solar?
This option is certainly one to think about. I have a small roll-up solar panel which I’ve used from time to time. Most of my activations are fairly short and the extra weight isn’t worth the effort for me. However, if you want to combine SOTA with some overnight camping, then this might be worth having. I use the Buddipole Solar Battery Charge Controller. This is a small, compact and very lightweight solar charge controller which works great with my rollup solar panel and my 4S4P battery pack.
I believe the future is very bright in the areas of portable power charging solutions. You may have seen small cook stoves which can be used to charge devices and batteries. Here’s a new Kickstarter project for a water powered charger. What will they think of next?
Until next time…
73 de KD0BIK