2101003, The "EMCOMM Hub" on Keller Sunday at 2000 hours (PST), "Discussion on non-mechanical DC power supply options" with Ray, N6KZM


  Mission Statement for the "EMCOMM Hub" on Keller:  

"Provide a networking environment that fosters sound Keller Peak Repeater practices with respect to emergency communications and preparedness."

o  All amateur radio operators are invited to participate.
o  To follow along you can find tonight's outline at hub.rivecg.net along with many past topics/information for reference.

For operational guidance; always refer to the KPRA guidelines found here:  http://kpra.net/guidelines.html

NOTE:  If you would like to be a featured guest who has an organization that meets the net criteria and you would like to highlight it in a subsequent net, please open a dialog with Rick, KK6CTT at rngr86@...  Please put "EMCOMM Hub" in the subject line for easy identification.


  • Facilitate education and training that draws willing amateur radio operators to serve as stewards of the Keller Peak emergency communications community.  Become "The Hub" of information that prepares us to efficiently recognize and adjust to situations where proper handling of priority and emergency traffic is necessary.
  • Allow groups and individuals who participate in emergency communications and preparedness to share their experiences while providing opportunities for operators to volunteer with the organizations that provide the best fit.
  • Establish sound practices within the Keller Peak Repeater Association that recognizes and addresses the "greater good" principle in the eventuality the repeater becomes "The Hub" of emergency communication operations.
  • The flow of the net will include the following but will remain flexible:
    • Any updates from KE6RYZ, Dennis concerning the repeater.
    • Guest speaker(s) sharing personal, agency or organization information (see "scope of this net"):
      • Personal experience due to an event or personal knowledge based on work/volunteer experience.
      • Governmental or Nongovernmental organization (NGO) viewpoint.
      • Or, the club frame of reference.
    • Public Service Announcement:
      • Wrap up with something relative to the group that ends the net on a positive note.
Frequently heard courtesy tones on the repeater:
  • Dah Dit Dit Dit (- . . .):  "B" signifies the repeater is running on backup power:
    • "Routine" QSOs should be avoided.
    • Brief "Priority" and "Emergency" traffic may be passed which may include directing operators to another repeater or simplex net.
    • Net controllers please refrain from conducting roll calls and use the net to share or exchange only important information.
  • Dah Dah Dit (- - .):  The "G" tone identifies power is derived through onsite generator backup power:
    • "Routine" QSOs should be avoided.
    • Brief "Priority" and "Emergency" traffic may be passed which may include directing operators to another repeater or simplex net.
    • Net controllers please refrain from conducting roll calls and use the net to share or exchange only important information.
  • Dah Dit Dah (- . -):  The "K" tone signifies the repeater has dropped and is awaiting the next station.
  • Dah Dit (- .):  The "N" signifies the repeater is in "net" mode.  This may include automatically or manually linked reflectors/nodes.
  • IRLP and EchoLink Check-ins:  Call, Name & Location
  • RF Check-ins:  Blocks of 5 calls:  Call, Name & Location
    • We will:
      • Check-in participants as we get comments, questions, and suggestions.
      • Ask for check-ins at the end of the net (time permitting).

I.    Announcements:
  • Nets to come in the near future:
    • Join Rick, KK6CTT on 10/10/21 as he shares his experience with remote operations and being "Off-Grid."
  • Licensing and testing:
    • Amateur License Testing, every 2nd Tuesdays of the month 0800, $15 Exam fee
      • American Legion Post 426, Yucaipa, 12167 California St. TO REGISTER send Email to wd6h@...
  • Join W6LIK and the Joint Seal Beach ARES/VA on Monday, 11 OCT 21, 1830, for an open Zoom meeting with YouTube sensation from Ham Nation, Josh Nash.  Josh will discuss "Grab and Go Portable Ham Radios".  Josh is always a show-stopper...  Hope you and your friends can join us that evening.  See you then, Midge W6LIK
  • Great ShakeOut Plans?
    • West Riverside County ARES:
      • 21 OCT 21, 10:21, check-in net on the Moreno Valley RACES repeater on Box Springs.  449.300 (-) 103.5 PL.
      • 23 OCT 21, 0900-1030, information continues to trickle in.
        • All operators welcome to participate
        • Will provide an example of "meeting" on Keller, providing status and moving to a resource net based on area and activity.
        • Other operational expanded exercise tasks.
  • Local Tech Net on the W6JBT Repeater:  https://w6jbt.org/
    • Each weekday morning the “Tech-Net” is held from 0700-0800 on the W6JBT repeater or Echolink at W6JBT-R.  This net is designed to bring local hams together to talk about radio issues, new products; questions and answers about everything “ham."
  • Looking for more net time?  We've had some good reports of a welcoming repeater further west that holds two-weekday nets at 0900 and 2100 hours on the Catalina Repeater:  http://www.cara.radio/
  • Of course, there are the several Keller Peak nets featured here:  https://kpra.net/nets.html
  • Any other announcements?  Please send them to Rick, rngr86@... if you would like to make an announcement during the net.

"Discussion on Non-Mechanical DC Power Supply Options"

Presented by Ray N6KZM, Solera Radio
Background info:
  • On the weekend of  August 20th, I volunteered as a radio operator for the Kodiak 100 Ultra Marathon at the Burns Canyon runners' aid station.
  • This is a multi-distance running race through the backcountry of Big Bear Lake; northeast of Los Angeles.
  • Distances were 5K 50K 100K and 100-miles on dirt trails.
  • The race began in the morning of one day and ended in the afternoon of the following day.
  • We had 14 runners' aid stations located throughout the course. These stations had 6-8 volunteers devoted to ensuring the safety of the runners by providing refreshments and rending medical assistance if necessary.
  • Most importantly the aid stations allowed for the tracking of runners on the course.
  • Due to the remote locations of the stations, cellular communications were strained at best.   Ham radio operators bridged a potential collapse of communications for the aid station volunteers and of course the safety of the runners.
  • Radio operators were also tasked with keeping race officials informed about the runners' location, condition, and potential race timelines.
  • Radio operators used laptops and data bursts over the cellular system via software called "Runners' Track."
  • When cellular service was unavailable (two aid stations had zero services),  radio operators relied on "passing messages" via voice transmissions.


My Issues:
  • Power Management
  • Not enough supply of power

My Journey regarding Power Supply Upgrade:
  • Mechanical Power Supply
    • Fuel Generators 
    • Wind Turbine
    • Water Turbine
  • Non-Mechanical Power Supply
    • Solar Panels
    • Batteries
      • Lead Acid
        • Lead-acid batteries are by far the most popular and most used rechargeable batteries. They have been a successful product for more than a century. Lead-acid batteries are available in several different configurations like small sealed cells with a capacity of 1 Ah to large cells with a capacity of 12,000 Ah.
        • Sealed or VRLA (valve regulated lead acid)
        • Do not require watering, can be used in any orientation, and use a valve for gas blowoff. For this reason, both designs can be called maintenance-free. However, it is quite common to find resources stating that these terms refer to one or another of these designs, specifically.
        • AGM (absorbent glass mat)
        • Plates are separated by glass fibers soaked in electrolytes.
        • Gel
        • A mixture of silica gelling agents in the electrolyte. This converts the formerly liquid interior of the cells into a semi-stiff paste, providing many of the same advantages of the AGM. Such designs are even less susceptible to evaporation and are often used in situations where little or no periodic maintenance is possible. Gel cells also have lower freezing and higher boiling points than the liquid electrolytes used in conventional wet cells and AGMs, which makes them suitable for use in extreme conditions.
      • Lithium
        • Li-Ion, these batteries have a significantly high energy density, high specific energy, and longer cycle life. Other main advantages of lithium-ion batteries are slow self-discharge rate and wide range of operating temperatures.
        • LiFePO4  is comprised of the "Periodic Chart" abbreviations for chemicals used in the battery. Li = Lithium, Fe = Iron, PO = Phosphate. 


San Gorgonio Pass ECG


Build your own Battery Box
(Source: https://roofnest.com/blog/2018/10/31/diy-portable-camping-battery/)

The goal was to create a portable power system that we could easily bring camping, charge while driving, and that would power our 12V portable refrigerator overnight. We also wanted something that would provide power for other small devices, like lights or phones.

We’ve chosen to use a 35Ah battery, but you can use another size battery according to your needs.

To build a portable camping battery you need:

  • A battery (duh)
  • Some outlets to use the power, and
  • A charge controller that takes power from an outside source (like a cigarette lighter or solar panels) that efficiently charges the battery.

Here’s your parts list:

35Ah Battery $68
Battery Box  $12
Charge Controller $21
12V Outlets $12
12v Charging Plug $8

Total cost: $121

How to Assemble Your DIY Portable Battery

Now that you’ve got all your parts together, it’s time to plug in all the pieces.

Step 1

Attach the charge controller and 12V outlets to the outside of the battery box. We just use small screws, but you can also drill small holes into the box to use nuts and bolts.

Step 2

Wire the battery to the charge controller. Cut off about 12-15” from the 12V plug cable and use this. Attach the leads to the battery (red=positive; I drilled a hole in the battery box to thread the leads through. In the photo, we drilled the hole near the top, but would suggest drilling it near the bottom where the controller is).

Then, strip the free ends and insert them into the battery terminals on the charge controller.

Step 3

Wire the 12V outlets to the battery in the same way Again, we drilled a hole and left the fuse on the outside of the box.

Step 4

Finally, attach the 12V plug to the charge controller by stripping the free ends and inserting into the “solar” leads on the controller. (Note that charge controllers are designed to accept varied electrical current and output a “controlled” current to charge batteries. The controller we’re using is designed to accept up to 18 amps of current, so it works with most vehicles’ cigarette lighter. If your vehicle puts out more than 18 amps from its cigarette lighter plugs, you may need a different controller).

And just like that, you’ve got portable electricity to power you through your next outdoor adventure. We won’t be shooting for a patent with this thing, but it’s one of our many DIY camping hacks that have helped make our time sleeping under the stars just a little brighter (okay, a lot brighter).

Source: https://www.qsradio.com/shop-now.html#!/Power-Supplies-and-Batteries/c/13274013/offset=0&sort=normal

What is a portable power station and how does it work?

Portable power stations (also called gasless generators or battery-powered inverter generators)  are devices which can store electrical power in an internal battery for later use. In essence, they are giant power banks. Portable power stations usually provide electrical power of up to 1000 W, although there are exceptions and devices with much higher capacity can be encountered on the market. However, their portability is questionable.

The battery capacity of a portable power station is quite commonly limited to roughly the value of their power in watt-hours (Wh), e.g., a 1000 W generator stores 1000 Wh, which means that they can provide their maximum output for up to an hour at the end.

Since most portable power stations aren’t necessarily large and run from a battery, they usually tend to be much lighter than units with combustion engines. Some of the lightest units weigh less than 10lbs.

Among the most popular brands of gasless generators, we count Jackery(opens in a new tab)Goal Zero(opens in a new tab)Ecoflow(opens in a new tab)Bluetti(opens in a new tab), and Rockpals(opens in a new tab).

Amp-Hour (Ah) or Watt-Hour (Wh)? How to Properly Spec Energy Storage 

(Source: https://www.linkedin.com/pulse/amp-hour-ah-watt-hour-wh-how-properly-spec-energy-alkuran-ph-d-/)

We will get shortly to the technical difference between (Ah) and (Wh), but generally speaking, (Ah) is used more for cells and batteries, while (Wh) is used more for energy storage systems, although, technically, you can use either term for any of the three categories.

Amp-Hour (Ah) is a unit of measurement that describes accumulated electric charge over time. One (Ah) equals the amount of charge (think electrons) moved by a current of one Amp for one hour. Alternatively, 2 Amps for half an hour, and so on. The advantage of using (Ah) is that it is somewhat independent of the series losses in a battery.

Watt-Hour (Wh) is a unit of measurement that describes accumulated energy. One Watt-Hour (Wh) is the resulting energy from operating at a power of 1 Watt for 1 hour. This can be, for example, 1 Amp at 1 Volt for one hour, or 4 Amps at 0.5 Volts for half an hour, and so on. The Watt is the product of Amps and Volts.

One analogy to think of is pumping water into a balloon or a bladder. (Ah) would be an indication of how much water the balloon holds, regardless of the effort it took to put it into the balloon. (Wh), on the other hand, is a measure of the work it took to pump the water into the balloon, or the work resulting from letting the balloon force that water out. It is a function of the amount of water and the effort it took to put it in.

The amount of water into the balloon (Ah) is typically the same as the water that will come out of the balloon. So, (Ah) round trip efficiency is typically very close to 100% for rechargeable chemical batteries. However, the amount of effort it took to put the water into the balloon (Wh) is usually higher than the resulting work from letting the balloon push that water out. So, the (Wh) round trip efficiency is typically much less than the (Ah) efficiency, especially for electrochemical rechargeable batteries.

 Why Does it Matter?

Let’s look at the scenario of an aging battery. Two major things happen with an aging battery:

  1. The actual charge holding capacity of the battery decreases.
  2. The losses (resistance) of the battery increase.

It is easy to identify the capacity loss when using (Ah) because it is somewhat independent of the series resistance (losses) of the battery. However, this becomes challenging when using energy measurements (Wh) to describe capacity, because, energy measurements will factor in the voltage at which current is fed into/out of the battery. And that voltage is influenced by the voltage rise across the series impedance of the battery, which is hard to quantify.

On the other hand, using (Wh) is more meaningful for applications and energy storage systems, as users can relate to the number, and it doesn't require knowledge of the voltage of the system. Stating the (Ah) only of the battery is not enough to describe the work it can do, you'll need the voltage too. Additionally, (Wh) is a good way to describe energy storage systems that have energy conversion units like DC-AC inverters and AC-DC chargers. For example, the capacity of a 240V AC-coupled energy storage system can be easily described in (Wh) regardless of the actual working DC voltage of the battery.


If the capacity of a Lithium Ferrite Phosphate (LFP) battery didn’t change over time, but the internal resistance went up from 2 mOhm (of a new battery) to 4 mOhm, then at 10A charging current:

  • New battery charging voltage rise is 10A x 0.002 Ohm = 20 mV higher than the internal voltage of the battery.
  • Aged battery charging voltage rise is 10A x 0.004 Ohm = 40 mV higher than the internal voltage of the battery.

So, the charging voltage will be 20 mV higher due to aging, and the resulting charging power will be 200mW higher than that for a new battery. During discharge, similarly, the power output will be 200mW less than that of a new battery. So, if this was the case at a nominal voltage of, say, 3.2V (approximated over the charge / discharge period), then:

  • True charged (Ah): 10Ah per hour
  • Internal charging power: 32W
  • Actual charging power: 32.2 W
  • True discharged (Ah): 10Ah per hour
  • Internal discharging power: 32W
  • Actual discharging power: 31.8W , which is only 98.8% of the actual charging power, at the same ampacity.
  • For a new battery, the number similarly would be 99.4%.

This means that if capacity is compared using (Wh) there will be an apparent “fake” capacity loss of ~0.6% just because of the change in the internal resistance, although the true capacity (Ah) didn't change.


Both (Ah) and (Wh) have their pros and cons in describing the capacity of a battery. The key is to always state the method used, especially when describing capacity degradation and warranties. It is recommended that capacity retention literature draws the distinction between two things that happen to the battery, mostly due to aging and cycling:

  • True capacity reduction, measured in Amp-Hours (Ah), or as a percentage of the initial (Ah) capacity.
  • Efficiency reduction, stated either as Round-Trip Efficiency (RTE), or as losses.

The (Wh) numbers can be calculated from the above, along with the voltage, when needed.

It is also worth noting that all performance measures should also reference the operating conditions at the time of capturing them (Charge rate, temperature... etc). For example, RTE will vary as a function of temperature.


San Gorgonio Pass ECG

Margaret Bash W6LIK

Ray, What a great presentation. It was packed full of interesting and worthwhile information. I learned so much especially about those gas production in batteries. This was new information.

In the new year, would you be available to give this presentation to our ARES group via zoom. .The presentation would be so beneficial to our group. Many are just thinking they want to develop "to gom boxes.

Thank you for sharing your experiences and giving us such thorough details about batteries.

Midge W6LIK
Emergency Coordinator
Seal Beach/Los Alamitos


Hi Midge,

I am so glad it was worth your time to attend the Net.

It would be a privilege to present this info to your ARES group.

73 & TTFN

San Gorgonio Pass ECG

Margaret Bash W6LIK

GREAT....Thank you, MIdge