PowerFilm Lightsaver Max Microsoft Surface Charging off grid

Hello Operator.
Many of you have asked about charging the Microsoft Surface Go 2, using the PowerFilm Lightsaver Max.

The beauty of the PowerFilm Lightsaver Max for the off grid QRP OP are its integrated components, and its size. Operating QRP off grid for an hour is easy. We simply operate off of our internal batteries, then recharge at home, Operating for more than a couple of hours, or even days at a time, we need a portable power supply which can be easily recharged in the field. It is Childs play to build a 3S lithium ion battery pack. Add the ability to recharge it in the field and things start getting bigger eg charge controller, wires, connectors, … Protect the battery from over charge, over discharge, short circuit, … then things become much more complex. The Lightsaver Max is the perfect lightweight portabe power solution for most if not all QRP to 20 watt field radios, drawing less than 5 amps of current. Add on the ability to recharge itself in the field, and rather than a boat anchor when the battery is dead, the operator charges it, and continues the adventure.
Check out my video on the Lightsaver Max as a QRP power supply.

Getting started
There are several things we need to do in order to use the PF LSM as a power supply for the Microsoft Surface Go 2. I started by modifying a couple of the cables which where included with the Lightsaver Max. I also purchased an adapter from JGo Tech on Ebay. You’ll need to decide if you’d like to power just your Surface tablet, or for most of us reading this blog, the Surface Tablet, and a QRP radio. If so, we will need to make a custom splitter cable. I made a cable with one coaxial plug for the LSM on one end, then split that cable into two anderson powerpole outputs on the other end.

Cable mod
The Lightsaver Max comes with a cigarette lighter socket adapter. While it can be left unmodified. I chose to shorten the cable adding powerpole connectors on the wire end.

Anderson powerpoles we’re also added to the DC coaxial plug, previously attached to the cigarette lighter socket. Now that Jgo Tech adapter can plug directly into that socket.

Surface Go 2 adapter
Voltage and amperage requirements for the Microsoft Surface go is 15 volts 3 amps for a desktop like fast charge experience. The Jgo tech adapter has a built-in boost converter, boosting the 12 volts from the lightsaver Max, to the 15 volts required for the Microsoft Surface Go. This may also be compatible with other Surface tablets, but I have not tested them. If you are using it and the Lightsaver Max with an amateur radio, they are both RF quiet!

JG0 Tech Adapter
The JG0 tech adapter is a cigarette lighter socket adapter and surface tablet cable. One end of the cable is USB-C. The other end is the Microsoft Surface tablet connector. The cigarette socket adapter has a single USB-C PD output with 5, 9, 12, 15, & 20 volts.
– The J-Go Tech Surface Cable from Ebay https://ebay.us/koCRBk
– J-Go Tech USB-C PD 45 watt cigarette socket adapter https://ebay.us/4tHzKG

The following radios compatible with the Lightsaver Max.

  • Icom IC-705
    Full power TX. Will charge from USB for 5 watts output, or the the PF Lightsaver Max 12v output, for a full 10 watt output on the IC705.
  • Lab599 Discovery TX500
    The LSM will power the TX500 to full output power. When using the Lab599 piggyback battery pack, the LSM can charge the pack to 90-95% of full, since the minimum voltage for a full charge, is slightly higher than the LSM output voltage. When using the piggy back battery pack, use the LSM 12 v output attached to the piggy back batteries input. This will charge the piggyback battery pack, and power the TX500.
  • Yaesu FT-81x
    Will power or charge the FT-817 or FT818 from PF Lightsaver Max 12v output for a full 5/6 watts output. The PF LSM also charge the 81x internal batteries., while fully powering the rig.
  • Elecraft KX2
    Will power Elecraft KX2 to its full output power, using the PF Lightsaver Max 12v output.
  • Elecraft KX3
    Will power Elecraft KX3 to its full output power, using the PF Lightsaver Max 12v output.
  • Xiegu X5105
    Will power or and/or charge Xiegu X5105 at full output power using the PF Lightsaver Max 12v output for a full 5 watts output. Will also charge the X5105 internal battery, while powering the radio. Note: The max output voltage of the LSM is lower than the X5105 charge voltage. Therefore, only a 85-90% charge can be achieved. My recommendation, disable external charging, and use the LSM to power the rig externally.
  • Xiegu G90
    The LSM can power the Xiegu G90 to its maximum output power of 20 watts. The G90 does not have internal batteries, so we use the LSM as an external power source or portable power supply.
  • mcHF
    The LSM can power the mcHF to its maximum output power. I have not tested the version with internal battery yet, but hope to get one here to test.

For those of you who haven’t seen the portable power for qrp video yet, I did a video showcasing the Lightsaver Max, as a power supply for my portable amateur radios.

The Lightsaver Max can be purchased directly from the PowerFilm website or from California PC who will also begin shipping the Lightsaver Max overseas.
– California PC: https://californiapc.com/Portable-Solar-Chargers/PowerFilm-Solar-LightSaver/PowerFilm-LSM-1.html
_ PowerFilm Solar: https://www.powerfilmsolar.com/oh8stn
On the PF website, use my call sign as the discount code.
For California PC, use “CPC10LSM1” without quotes.

Lots of creators use buzzwords like Off Grid, Grid down, … while never leaving the grid for more than an hour or two. We can really define off grid as being “grid independent”. A battery which can’t be recharged in teh field is no longer “off grid friendly”, once the battery is depleted. At that point it is simply a boat anchor, we need to carry back home.

For the QRP field radio operator, the PF Lightsaver Max can be an all in one portable power solution. It can also be our solution for a fixed station power supply as well. The LSM can easily power the Icom IC-705 and Microsoft Surface Go 2, by splitting its output into two DC lines. One for the 705, the other for the Surface. The USB-C charging port on the Lightsaver max can be used to simultaneously charge the Lightsaver Max, while powering your QRP rig and tablet. It can also be connected directly to a 30 watt solar panel. Its up to you!

If you have specific questions please feel free to leave them in the comments. I’ll answer them by updated the post with the question and the answer.

Julian oh8stn
YouTube: http://www.youtube.com/c/oh8stn
By me a rootbeer: https://paypal.me/oh8stn/1usd

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  1. Julian, I noticed you no longer use the Buddipole Mini Power Controll ?, is there a particular reason ? I wonder if the PF-Lightsaver max can be charged , using a Powerfilm , eg 28 attached to the Buddipole Mini , ?

    • Hi Edwin.
      I don’t use the PowerMini in winter months because its low light capabilities are not sufficient to charge LiFePO4 batteries at this latitude. Instead I use a Genasun GV Boost controller for 4S LiFePO4 which works incredibly well in low light. Take a look at my Lightsaver max video https://youtu.be/3G0GxVuReLg it shows how to connect a solar panel directly to the Lightsaver max, without a charge controller. The 28 watt panel is perfect for connecting directly to the Lightsaver Max, as the Lightsaver amx has a charge controller integrated.
      Julian oh8stn

  2. Hello Julian,

    Can you please provide the spec of your Microsoft Go 2?
    It this the base model or the M3 variant recommended by several Youtubers?

    Yoram 4Z1YR

    • Mine is the base model and works very well. if you can afford it, the M3 is even better.
      Julian oh8stn

  3. Most solar array output around 18v, any suggestions on a good DC to DC converter to give 13.8 (or what you set it to) and charge a battery at the same time? VE3XET

    • I don’t use dc-dc converters for battery charging because they don’t shut off automatically. There’s a risk of overcharging when using them. I use pure charge controllers. My favorite at the moment is the Genasun gvb-8 most solar charge controller.

  4. Powerfilm is not shipping overseas currently, so my inoperative Lightsaver Max warranty return is problematic. I suggested they send the parts as a kit. They’re very good responding to emails, so far.

  5. Julian, can the Lightsaver Max be charged externally? Sorryr if I missed that bit in your writings. I own about 5 other PF products but was wondering if I hooked my 30watt PF panel up to the lightsaver max if it would speed the charging process. An 18AH battery is a lot to fill up afterall.

  6. Julian. What are the longest cables that you’ve made for the Lightsaver Max? I could see the need for a longer cable if you had the radio in a tent, and the Lightsaver Max was placed outside. Thx.

    • I usually use a small solar panel in addition to the Lightsaver Max. The solar panel is 5 meters outside the tent oh, and the Lightsaver Max is right next to me. So it doesn’t actually answer your question but probably three or four meters.

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