Scott, I have been thinking about parsing down my kit also and moving away from the 4S1P A123 26650 packs I made, to use the latest 18650 cells (all LiFePo4 type).
I traded some stuff with a co-worker for some NCR18650PF cells that cost him like $2/each on ebay… I intend to place them into a holder from ebay for 5V o/p and then use them with a 5V / 12V converter to run my MTR5b. This should be a lite-weight solution… here’s some weights…
4s1P 25650 pack… with wire//powerpoles = 11.7oz // 330gm
4 18650 cells only = 6.5oz // 184gm
The DC/DC converter mentioned above weighs 1.1oz // 32gm (off amazon for $9)
The power block shell was $15 I think… I didn’t receive it yet, not sure on weight… e-wag @ 3oz.
18650 Battery only holders are available on ebay // amazon
also, making a 4S1P 18650 pack in the ~200gram range would be possible.
There are a couple of advantages to use a holder over making your own pack… for instance… for air transportation you can place the cells in the Cell-phone re-charger box and then swap them to your own pack holder or use the DC/DC.
For activations I carry two A123 2.5 Ah LiFePO4 batteries which I bought from Buddipole. However, I have never needed more than one for two activations. They require a special charger - I use a Cellpro Multi4 which provides a balanced charge on all cells unlike some other chargers.
Scott, further information.
I used one of my LiFeP04 packs 4S1P A123 26650 cells for 4 CW activation’s Saturday using a KX2. Recharging the battery required 1702mAhrs.
Have you considered buying the 3.0 Ah version of the Bioenno battery you already own. Simple switch since you already have the chargers and connectors right. You’ll drop 0.2 lbs and have plenty of juice.
Then start looking at other ways to lighten your load. What are you using for an antenna? Your CW key? etc.
For example, I own one of the whiterook paddles and while they are not even remotely as nice as the te-ne-ke or other offerings the plastic design is disgustingly light. In fact the website states 1.2 ounces.
If you are using coax consider switching to RG-174 if weight is a priority and you are using something heavier. And if you have more length then you need, get something shorter.
How are you logging? Are you carrying a clipboard and pen and paper? If you have a cell phone on you already then ditch the paper and pen. Either download a logging app or use a sound recorder and log the qso’s at home. Just announce the time right after starting and any band changes on the recording and go from there.
If you are using an antenna support like a mast and could be using trees, lose the mast. Instead get some rope and throw a rock you find at the summit.
Is your antenna built using the lightest wire you can get? 26 ga wire can shave some weight off your antenna system.
Small things, and don’t limit yourself to the battery. Weight savings come from elimination, multipurposing and optimization.
