Portable Ham Radio on Solar Power: Current consumption

Reducing current consumption is critical to an off-grid ham radio station on solar power. In this episode we review whether or not a QRP radio like the Icom IC-705 with an amplifier (DIY599 PA500) is more efficient than a QRO rig like the Yaesu FT-891 on its own. We specifically want to understand receive current load, transmit load or current draw and efficiency of the transmitter at certain watts.
If you find this video interesting, be sure to watch "How to solar power your portable ham radio" series: • Solar Power your Porta...
We traveled to Hailuoto Island for some portable ham radio and to answer the efficiency question. We took along the 2x 100 watt Powerfilm FM16-6000LT solar panels, a Yaesu FT-891 & 576wh Solar Generator, and an Icom IC-705, DIY599 PA600 amplifier and a 256 watt hour solar generator. The goal was to test which station was more energy efficient, while running on solar power. With the lessons learned, it is now possible to build an incredibly efficient portable ham radio station for off grid, or grid down ham radio
73
Julian #oh8stn
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- PowerFilm Solar www.powerfilmsolar.com
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- PA500 Amplifier www.diy599.com
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[@dougbas3980]

Great! I did FT857d with Build-a- Pi. Now I am upgrading with IC-705 and PA500. All your videos guide me in being more EMCOMM ready. That is why I support you on Patreon. THANK YOU. BTW, I really like Oliver from DIY559. What a great unit the PA500.👍

[@OH8STN]

Thank you Doug 👍

[@robertchambers5821]

Julian: You've changed my buying decision with this video! This is an enormous jump forward. Thankyou. 8P6RC

[@FlyGuyToo]

Another great video Julian. I have the IC-705 and love this radio, but it really does need an amplifier in certain situations. This is the first time I have seen or heard of the PA 500, so I hope you do a review on this product and let us know how we can buy one. 73's de W4LJT

[@dougbas3980]

Larry, the DIY559 is great! They are on a rather long back order. Hope you an get one😀

[@jimkunkle2669]

I’m still studying. That said, your style matches my concept of what I want out of a radio. If manufacturers made a low current draw QRO rig I’d buy it. Current draw trumps power output.

[@mdouble100]

Excellent, very instructive video. I have and FT-891 with tuner in my truck for mobile use. I also have a solar panel and a RedArc charge controller which combines solar and vehicle power inputs to a small deep cycle gel cell lead acid battery. This works great in the truck but I would not want to pack it into the field as a man-portable station. Your videos continue to inspire me to lighten the load and get out well off-grid. Here in Canada there is a lot of territory that is really way off-the-grid.

[@_Argos]

no clue how i find to this video after a 48h day but this voice is like from a nature documantery very smooth gn8

[@joshuagarrett4879]

It's Pragmatic thinking and real world testing that makes this one of, if not the best Ham youtube channel I know about. Love this channel, and you 100% have a voice for radio :D

[@neoretrophoto9198]

Whether QRP or QRO, Its important to be warm and to have sausages!

[@MidlifeRenaissanceMan]

Yes. Especially the the sausages.

[@edingacic546]

Ok I know what we need - we just need now a good handheld HF radio forget all this :) In the past they did make HF handhelds as I found out but now we really need one - :)

[@OH8STN]

I agree. I'm old enough to remember those outstanding HF handheld we had back in the day. They're only limitation was bands and power output . They were battery operated could utilize handheld microphone or external paddle and often deployed with a resonant antenna. Ham radio contesting killed development of portable rigs like that.

[@polymath5119]

Taking the amp out of service when not needed is appealing for even greater reduction of power consumption. Herr Harms at DIY599 indicated via email last week that they are currently having difficulty sourcing components. He also noted they don't have a delivery date for North American customers, and don't yet have FCC certification for the PA500. My bet is that will eventually come to fruition, with patience.

[@jamesrkelly76]

I think weather proofing radios is higher on the list. After coming from exclusively using military radios in the arctic, jungle, temperate and desert expeditionary environment, i am suprised to see how little thought goes into designing mobile radios for outdoors use. Thats not even considering and ruggedisation. I'd be interested to hear how you think the 705 would fair for a week of well below zero temps during the day to the high humidity in a shelter during the evening.

[@perrseb5772]

I had the same questions, but this guy has a hot tent so it means he can always operate in dry and warm environment.

[@OH8STN]

Bingo! The hot tent is the key factor. Even so, I completely agree with the initial comment of how little fog goes into portable radios, operating in inclement weather. The handheld radios these days are much better, many being IP67 rated. Sadly, this isn't true for HF radios.

[@terryb3511]

Really informative reviews Julian. I received my PA500 yesterday and drive it with my IC-705. I have the new version with built in Vox keying, so no keyline needed. What a great little amp. Very small and beautifully crafted! It's a really good replacement both size and current wise, for my Elecraft KXPA100 which was a really solid amp, but not nearly as portable. The PA500 is a perfect amp for the field and POTA. I'm using a 12V 6Ah Bioenno battery for the PA500 and the built in battery for the IC-705. It gives me a lot of on air time.. Great little amp.

[@reidlanham2011]

Great video, thank you for the comparison!

[@Exarach]

Such a fantastic channel. So much A+ info here

[@kb6lcw99]

Always great info!!!

[@vironpayne3405]

I love your videos Julian! But, I am also glad that portable to me means throwing stuff in the car and heading to a park. A number of years ago when I was more active I did toy with the idea of putting my FT-817d on my bicycle. HF bicycle mobile could be fun in my area as I live near the Indian River lagoon that has scenic road that is great for bicycling.

[@iamnobody9542]

Funny - I came to that same conclusion many years ago with my FT-817 and Tokyo Hi Power HL-45B and the LDG that runs from 0.1 W to 125 W. Got it all covered. Tested, works. Folks do notice the difference between 5 and 45 W output. My QRO setup is my old IC706MKIIG with what ever LDG I happen to grab. That rig kuz it will run to a bit lower voltage than my 7000, BUT I gotta lug my 75# 100AH along for that (U.G.H.!) The QRP setup runs on my 17#, 17 AH, and to a much lower end voltage. Plus,my old mil 30W solar handles that pretty well, too. Jerry wa2omu.

[@stefanhutter2662]

Julian, your videos are aewsome! You answer so many questions very structured and detailed. I own the 705 and really like it, but 10W sometimes is not enough. So i like to have the option (!) to amp it up today but to have a smaller package the next time. Greetings from JN88de

[@glennarrant3743]

Love your work. You are right about data, with out data all you have is an opinion

[@martensandstrom7343]

just ordered my PA500 :)

[@W9HJBill]

Nicw video. I have an IC-705 and a Xiegu G90 as well as the Xiegu XPA125B 100 watts amplifier. I haven't really looked into the power aspect so this was nice. I mainly use the 125B when I haul in my battery box with a 40Ah LiFePO4 battery in it. I have an FT-891 and FTM-400D in my truck for SHTF so I really never am out of communications most of the time. I personally like the idea of a separate amplifier because if I don't want/need to run above 10 or 20 watts, I just leave the battery box and amplifier at home.

[@ferdinandfrozenstein]

I actually do the same on VHF/UHF, I realized that running IC-705 with an 80W amp portable eats batteries much slower than my FT-991A, exactly due to this -- much lower RX power consumption. And, since my RX:TX ratio is high in favor of RXing, it really makes a change. More cables, more money spent, but it works for a longer period of time on the same batteries, and finally, it's more lightweight. For VHF, I use RM Italy LA-145.

[@LanWolf]

Nice video, like the size of the diylab amp, especially with an antenna tuner included. Was wondering what antenna system you used when reaching Japan ?

[@TheNoCodeTech]

Great content man, thanks

[@OH8STN]

🙏👍

[@DanielWiley]

Outstanding!

[@audioslaver22]

Julian, your videos are incredible! An absolute wealth of information for the newbie ham radio operator getting started. How does the Buddipole PowerMini2's performance compare to the Genasun GVB-8 (or GV-10)? I have a PowerFilm rollable 28W and 60W I'm currently using with the PowerMini2 and a Bioenno LiFePO4. In my opinion, the Genasun performance would have to be significantly better to give up the PowerMini2's convenient built-in information display and power distribution. I believe the PowerMini2's solar charge controller uses PWM (vs. MPPT) and I'm wondering what kind of energy generation I'm leaving on the table. Have a favorite between the two after using both for a while?

[@jimthvac100]

Using the PWM instead of a dedicated MPPT I suspect your loosing around 20% of the solar panels capacity.

[@svenonnerstad1494]

You might have a point there. I have been looking for a rig like the FT 891 for field and home use. But resently I am looking more at the IC 705 with an amplifier. Thank you for an instrctive video. 73 de LA1MSA

[@OH8STN]

Thanks for the kindness. It's incredible how this "low current draw" topic isn't covered in more depth. Hopefully the manufacturers are watching. Even if they're not, we can share these ideas and experience with each other. 73 Julian oh8stn

[@timelord1137]

It is interesting that the amplifier costs more than the TX-500 itself😀

[@gfinnstrom]

excellent video thank you for the information from KB7PPW

[@lyfandeth]

In the late 80's I bought one of the radical new portable LORAN-C units. And while trying to match up portable power, I found that the unit drew about 400mA but the LCD *display backlights* actually drew another 440mA. So simply killing the backlight killed half the power draw. It would be interesting to know if the IC-705 was purposely designed with a low RX draw, or if this is incidental to the display type, or other technology changes. (For instance, an OLED display costs more than plain LED but consumes a fraction of the power.) I'd urge you to contact Icom (etc) and see if they will comment on this. Perhaps it explains the cost of the IC705, or perhaps future QRO radios will change the balance.

[@user-vx5ru7gh7c]

Hi Julian, another very informative video. In my mind over the past couple of weeks has been, considering your relationship with Power Film, why you didn't go with using a Soltronix solar panel with the built-in PowerBoost charge controller. As the LightSaver series isn't shipping internationally until sometime in the autumn, I have been considering using a Soltronix rollable panel so your thinking on this would be helpful. 73

[@OH8STN]

I have the 24 watt Soltronix panel with integrated charge controller. Unfortunately these are not rollable, unless there's a new model I haven't seen. They are an option, but the size might be a limitation when man-portable. If you're car camping, or with some other type of vehicle they're probably really good solution.

[@Subgunman]

Thank you for the important info! Another question I have is how much of your grae comes from the states? For those items from the states what are customs fees like up north? Down here in SV land customs has become a greedy nightmare. Are the headway batteries you used sourced from an EU distributor or direct from China?

[@christopherhobbskn4ylp118]

Julian, your videos are excellent. I am waiting for a FT-891 to arrive as I don’t plan to go as far off grid as you for now and due to budget constraints. My QRP plans will be a lab 599 radio, battery pack and the amazing amp that ties it all together, but at 2 grand US that is a little steep for now. You do great work and really make us think through what we are doing and planning for. 73

[@OH8STN]

Thanks for the kindness. Agreed, the budget is another topic entirely. I don't think I mentioned it, but had to sell off a lot of gear to get here. The scariest thing was not being sure if the concept would work before selling off the other gear. You're going to love the ft-891. It has a much underrated receiver and I will miss mine. The tx-500 is a solid companion for the 891. It takes time but you'll get there. 73 Julian oh8stn

[@kirbymcd1]

I'd assume that radios like the 891 were designed with mobile use in mind and the power that comes with a vehicles electrical system. A different mindset might have resulted in a radio that viewed the finals like a pre-amp on receive and were able to be turned on or off and essentially be a build in amp vs running full time and consuming power. Just throwing that out there Lab-599...

[@OH8STN]

Best comment of the day! This is an excellent way to think about it, manufacturers should take note 73 Julian oh8stn

[@EdinGacic]

Maybe we can ask them to make a low power mode firmware option ? Might be possible to put it in a low power state? Maybe a hardware limitation and firmware would not help. Maybe someone with more knowledge can open it up and see if some mods can be carried out to arrive at a perfect rig for both worlds :)

[@OH8STN]

If only it were that simple. I think the first thing we need to do is convince manufacturers that this is actually desired. Most manufacturers have focused on contesting. Very rarely do they think about the low-power operator off-grid or in the field. So first we have to show them there's the need.

[@wirelessdj]

I am going to ask this again. Why is there not a QRP that works with an iPad?

[@OH8STN]

And they'll answer the same way, "you're preaching to the choir" :-) Ham radio development in some ways is in the Dark Ages.

[@groundzero.]

simple, you purchase an Apple product but you don't own it. You can use it but only the way they allow you to. it may be reliable but not safe, secure, or protect your privacy.

[@go2douglasvamateurradioandmore]

The more I get out in the field, the more I like less weight while still being effective. Ounces make pounds and pounds make pain. I do however like being able to have the power option if when necessary. I will likely get an ic705when funds become available after a shack/field radio like an 891. In the AZ desert water is more important than transmit power.

[@OH8STN]

Having lived in the Arizona desert, it's impossible to disagree. Thanks for the comment and kindness oh, very much appreciated.

[@MidlifeRenaissanceMan]

@@OH8STN yes. Here in Australia, water is first :-) Sausages are also up there too

[@perrseb5772]

I own a wood stove and a hot tent also, but new to ham radio. I wish to evolve in the off grid knowledge, and my first tought after seeing the solar panels were: is there a way to use the heat produce by the wood stove to charge the batteries…

[@bbarian]

Great topic and as usual, outstanding analysis. Another factor I like to calculate is portability from a mission oriented perspective. Like the military, I believe that having an option for base, mobile and, portable ops all wrapped into one system is fundamental. Your IC-705 based system, as explained in this video, allows for this option. Power up when at base or mobile; size down and run QRP when mission expands into portable realm. From an amateur perspective think car camping with SOTA excursions.

[@OH8STN]

Agreed. In fact this is the concept behind my current station. The ic-705 is my primary radio now. It's augmented by an amplifier which can be at home or in the field. Various Standalone antenna tuners or integrated antenna tuner with the amplifier. Finally various antenna options depending on how portable I want to be. Naturally there's also two different portable power options to tie it all together. It's a really good point you made. I wish I would have thought of it this way before finalizing this video.

[@bbarian]

@@OH8STN that’s the magic of your work, it helps us to all think outside the box and develop options to fit needs. You’re really leading the way.

[@N4TNA]

I understand that the receive to transmit ratio is in most cases 20% transmit 80% receive so I see the emphasis on receive current. However, I am curious about the Transmit current differences of the 2 radios at the same power level preferably 100 watts.

[@chuckcarter7864]

What tent are you using , it looks like it has a chimney pipe ?

[@christophercobb4317]

I am just ham radio what kind of home base unit do you think for beginners

[@terrybasom8642]

At 12 volts, I am still not sure what power the PA500 puts out. Is it a 40 or a 60 watt amp.. Of course it would be dependent upon the drive level, but does it require 16volts to put out 60 watts? Thanks in advance. .I really enjoy the reviews..

[@andrewmcdonald7077]

Julian were you transmitting LOS to a repeater tied into some connected network, or using the NVIS effect to achieve OTH (over the horizon) communications? I am a beginner.

[@OH8STN]

OTH with NVIS. Performance would have been much better with an actual NVIS antenna configuration. Thankfully the other station did the heavy lifting

[@EC5ABG]

Buen video!!👍73.

[@rttakezo2000]

Is that a mini helopad/marking just outside the tent for the drone?! :-)

[@OH8STN]

It is, it's also a color reference for the video editor :-)

[@bricktrainfan]

How do I get a DIP599 PA-500 amp? I have email the company for price and availability but have gotten no response. After watching your video I ordered a Discovery TX-500 and am looking to match it up with the PA-500. Keep these very informative videos coming. 73s W8GIL

[@OH8STN]

That's exactly how to do it. Send an email to Oliver from the diy599.com website. Nos ygerd is also a diy599 group at groups.io. I believe he's being overwhelmed with emails at the moment, since my last video. I spoke with him this morning so he's still alive :-) 73 Julian oh8stn

[@joewaco]

Absolutely would buy a QRO radio if they updated to enough to make it worthwhile. Low current draw, blue tooth compatible etc.

[@OH8STN]

#metoo 73 Julian oh8stn

[@Tump2010]

that is why I decided to hold on to my old ft-817 for POTA, it uses about half the current (around 700ma) receive over the 991a but there are no bells and whistles to the 817 but are they really needed.... lol debate for another video. :-D

[@OH8STN]

Agreed. I've been pretty hard on the little 817 and 818. Current consumption is something they are reasonably well with. We can definitely debate it all day though :-) Thanks for the comment.

[@fullsaildigital]

The answer is in between qrp and qro. The Xiegu G90

[@milcommguy5927]

Also please what is the amp draw comparison say at 45 watts between the two. Thank you

[@OH8STN]

I'll do a video on this in the coming weeks. Was actually a great question!

[@milcommguy5927]

Nice comparison, how about a cost comparison not including the battery or computers, just the radio/tuner/amps. Thank you

[@OH8STN]

Cost is subjective. We should always focus on the requirements, for an unbiased view of benefits and capabilities. Afterwards we can decide if it's worth it, or how to pay for it.

[@TomA-qy6jz]

A QRO radio with 350mAh RX current would do much for batterylife. The downside is that most QRO radios is highly inefficient on QRP levels due to the idleing current in the PA. One solution would be to have automatic switching to turn off PA below 10 watts or so and run on the drivers.

[@OH8STN]

That is a brilliant idea Tom.👍

[@OllieVK]

Was that power draw on the Yaesu including powering the laptop or not?

[@OH8STN]

No I didn't measure the laptop or the Surface tablet. This was just the radio and tuner for the 891, and radio and amp for the IC-705. If you're curious about current draw for all three, check out my previous video on Microsoft Surface with Icom ic-705.

[@thuff3207]

I am a big fan of QRP radios for same reason you are saying low current draw receiving. I to also have a small amp with a built in tuner. And yes together they still lower current than any QRO radio I have seen. I don’t use my amp often except for digital modes there you need the help.

[@OH8STN]

Thanks for this comment. Some people are very skeptical about the qrp radios plus amplifier. So far it seems like a really good option. Thanks for the comment and the kindness, It's very much appreciated. 73 Julian oh8stn

[@alexn78666]

That's funny, digital is usually considered a lower power mode than voice..

[@OH8STN]

Alex, the difference in current consumption is the point. Not how much tx power people choose to run. The goal is a more sustainable station, with higher output option if required.

[@metaller_alex]

Why not TX-500 ? It has even lower RX draw and can be screwed toghether with PA500 as far as I know.

[@OH8STN]

Tx-500 is another good option. As I mentioned at the beginning of the video, It doesn't matter which qrp radio. I used the 705 because that's the radio I have here. 73 Julian oh8stn

[@frankwc0o]

Super. When are the PA500's coming out? This is the first time I see one. I hope you are making a video to show how it works and how you like it.

[@alexn78666]

They're already out.. a simple Google would answer that

[@yakovdavidovich7943]

@@alexn78666 nothing but "contact us" stuff on the web site. Empty blog. Found a couple blogs about the PA500, but no links to buy one. Normally, "being out" implies that they can be bought somewhere...?

[@arconreef]

Considering the enormous power draw of the "portable" rigs coming from Icom and Yaesu, it appears that they are either unaware of the market for off grid/emergency radio communication equipment within the HAM community, or believe the market is too niche to be worth their time. Unless there is a sudden explosion in the popularity of off grid comms, I don't see this changing anytime soon. These days I think the big 3 in Japan view HAM radio gear as just another way to drive down the cost of manufacturing by increasing volume. I suspect their focus is on signing contracts with military and other government organisations because that's where the money is really made. HAM radio is just an afterthought.

[@OH8STN]

You probably meant "mobile" rigs. The Icom IC-705 is extremely efficient. So is Elecraft KX, Lab599 TX-500, mcHF, Xiegu G90. FT-818 is fairly close to the Border.

[@bmmcwhirt]

Thank you. Is is a great help. I'm doing research right now but I'm leaning heavily towards the 705. My reasoning is this. I can set up an OTG base but still grab the radio and take with me when I leave camp. This gives the option of having slightly more power when at the base if needed but still have QRP on a hike or something. Currently I do not have any HF setup so I need to make sure of every component as this will be a decent investment. I do already have several Raspberry Pi, and I have a Surface Pro 7. It's a little more power hungry than a Surface Go, but since I already own it I will plan around that.

[@templehager4834]

Julian. Is that a trap on your MPAS 2.0?

[@templehager4834]

I found it! It appears to be an 80 meter coil from Super Antenna.

[@OH8STN]

That's exactly what it is. Apologies, I forgot to comment earlier.

[@glenhoff1443]

You know what is about to happen.

[@fbriansmith]

I was surprised you didn’t include any evaluation of current use in TX. I would be curious how they compared at 25W or whatever RF power you needed to complete communications.

[@OH8STN]

Why?

[@alexn78666]

@@OH8STN because transmitting is half of the objective? If the qrp+Amp uses 2x more power transmitting vs the QRO for example then the answer isn't as simple as "QRP+an Amp uses less power" Why wouldn't TX current consumption be revelant?

[@OH8STN]

That's a fair argument 👍 I will do a part 2 of this video showing the current consumption differences during transmit between the two. If we're talking about the ft-891, it has a lot of overhead built in. I already know it's consuming more current then a qrp radio and this amplifier at the same output level. I suppose there are some external amplifiers which are list efficient. Thankfully this isn't one of them.

[@fbriansmith]

I am headed out to do some off grid with my X5105 & the PAX100 amp. On the bench yesterday the RX draw with the PAX100 amp was 1800 mAmp (has internal fan). TX was 5 amp for 40W to antenna w/ 1 W from radio.

[@OH8STN]

It's raining here today but I'm operating from home. I'll do the same test and make a blog post of the results

[@MarkW126]

Very interesting video, but I think there’s one substantive thing left off: Cost. My FT-891 is much less expensive than the combo of ICOM radio + amp. To some of us, that’s a really important point. You also seem to travel very heavy. I’d love to see you do a video with a man-pack rig that you have to carry on your back. I bet the laptop would stay home them. :)

[@OH8STN]

If cost is relevant, then you have to include the cost of the much larger battery you require for your ft-891. Also the reduced operating time because it draws so much current. You'll be madmn packing a boat anchor at the end of the day when you go home. I'm probably something you don't know, 90% of the operations on the channel are man portable. I'm reducing the size and weight of my radio gear, so that I can carry a hot tent, food, and titanium wood stove. Those are things which are required at 65 degrees north. And because you're either a troll or haven't watched many of the videos, here's a man portable playlist just for you 😂😉 QRP Portable OH8STN: kzbin.info/aero/PLKMrdrsNkFA7evBmirvw27Ta9C_L8Tc79

[@MarkW126]

@@OH8STN I’m not a troll and I have watched quite a few of your videos, but not all. Thanks for the condescending comment. Much respect lost. And yes, I pack a decent sized battery and by the end of a SOTA expedition it’s heavy. But compared to what I got with the 817, it’s better combo of gear for my needs. You can stow your attitude; it’s neither necessary nor welcome.

[@OH8STN]

Read your initial comment. Some assumptions made were completely inaccurate. Anyway I get your cost argument. If my goal was casual ham radio up an easy Summit for a couple of hours, I might take that approach as well. Perhaps the difference is I'm usually out there for days at a time. If I carry the ft-891 and the battery required to power it, I won't be able to carry the gear, food and water needed for the rest of the trip. Those videos I shared also include some man-portable deployments with the ft-891. I'm not talking from a novice perspective. I'm approaching this topic from experience. That's why the very first thing I said in the video was we are focusing on "current consumption". If you'd like to discuss budget, that could be an entirely new video.

[@MarkW126]

@@OH8STN First assumption was on cost; my 891 cost less than what the ICOM cost by itself without the amp. I don’t know what you paid, but when it came out the ICOM was higher priced at the local store where I bought the 891. Second assumption is that the cost is important to some of us. I suppose that could be wrong. Third assumption is that you travel heavy; your kit seems to weigh a great deal more than what I pack. I don’t live at 65 north, but I do live in a much hotter climate at about 33 north. I don’t have to pack a stove as you do, but if you can find me a man-pack air conditioning unit that actually works, I’d love to see it, and if you can throw in a means of defeating mosquitos and deer ticks you’ll be a rich man. And in very general terms I’m pretty much guaranteed sunlight most days in my part of the world. My battery weights about 4.5 pounds/2 kilos, and I’ve never had a problem even on a partly cloudy day with heavy transmitting. I can pack three batteries if needed for extended periods of deployment, with one being an emergency backup that I built myself that weighs 6 or so ounces. What’s the weight of the laptop that’s clearly visible in the video? I don’t even pack a computer or a tablet as my needs don’t include digital. And I’ve seen a bicycle in some of your man-pack videos, so I don’t actually count that. My approach is perhaps more “casual” than yours (that’s an assumption on your part), but I’m mainly focused on EMCOMM situations that will last three to five days, as well as SOTA adventures and just taking the rig out to a nearby park. I take food and water into account as well, and I use a multi-layered approach to the pack(s) and gear I carry based on immediate known needs at the time I leave the house. I plan my movements around water, so I don’t always have to pack more than a way of boiling water and a Sawyer filter system if my water runs out, but I don’t have any handy snow to melt - ever. I’m not approaching this from a novice perspective either (another assumption on your part), but from a different perspective. I’m not sure what I said that rubbed you the wrong way. I actually said that I found the video interesting and I do appreciate what you’ve done here and with your entire channel, but the simple fact is that you’re gear is vastly more expensive that what I run (I’m fairly certain that the two solar panels in this video are more expensive than my entire kit), and that your gear appears to be considerably heavier than mine. And your response is to assume that I’m a troll or ignorant. Thanks for that.

[@OH8STN]

Fair enough, though it seems you didn't watch the video through or perhaps didn't understand it. What is shown here are two different systems. Ine with the ft-891 and a laptop, the other with the ic-705, amp and tablet. The only thing being measured is current consumption. What's rubbed me the wrong way was completely ignoring the point of the video which was efficiency and current. consumption for off grid comms. I try not to look at cost When approaching a solution to a technical problem because it's skews our objectivity. I rather find a technical to the problem then figure out how to pay for it. This as opposed to just looking at the cheapest solution. The ft-891 is great radio. Until recently I had one but I sold it, to pay for this amplifier. Cost is always an issue. As such, many of us we have to make sacrifices to meet those technical requirements. That's what I've done. It's not right or wrong, but it is much more energy efficient.

[@IgmuHammerer]

I wonder a comparison to VHF, UHF,... systems.

[@OH8STN]

More context please

[@IgmuHammerer]

@@OH8STN Are there power and device considerations that someone would need to think about differently building equivalent systems at shorter wavelengths. Like equivalent power amplifier version vs one box version. Example for me could be receiving weather satellite information (SHF & UHF receive only) and relaying that info regularly to my local 70cm or 2m repeater every hour. My only current solution are a couple SDRs, raspberry pis, for weather & 2m & 70cm analog and DMR HTs and adaptable connections to 12Vdc or 120Vac when available.

[@angelscomputers]

looks like there is no way to buy the PA500 amplifier, cant find it anyware on the net. It died?

[@christurner68]

Are the solar panels made in China?

[@OH8STN]

Powerfilm solar panels are manufactured in Iowa USA. Here's a FAQ from my website. oh8stn.org/blog/2021/06/24/powerfilm-solar-foldable-vs-rollable-solar-panels-and-others/

[@christurner68]

@@OH8STN thank you for the reply. I have been binge watching your videos and others too. I’m looking to take up this hobby as I love getting out in remote locations here in Australia. I’m looking at this for something to keep me occupied during those clear starry nights in the great outback of ours. I like the idea of this long range communication using low power and mobile technology. Cheers Chris 👍

[@kenthufford743]

- PA500 Amplifier is not available in the USA. It has not been approved, nor submitted to be approved by the FCC.

[@OH8STN]

This channel has a global audience 👍