How Many Chokes Do You Need?? Mailbag Monday
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- čas přidán 17. 09. 2023
- We're talking Feed Line Chokes. How many do you need? Can you Charge a LiFePO4 Battery with Non Solar Power through a Charge Controller? Are you Allowed to Put Wires In Trees For POTA?
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#hamradio #hamradiotube #parksontheair - Věda a technologie
There are devices called buck/boost solar charge controllers that have extended range inputs (i.e. 9V in can even charge 24V at 80+% conversion efficiency). They're usually integrated with MPPT, but have the additional boost (in this case) circuit. There's a bit of efficiency loss, but still better than what your tests were showing with non-boost MPPT. One example - Renogy markets their version (RNG-DCC1212-20-US) as a "DC to DC on-board battery charger", with 8 to16V input, and charging your choice of battery chemistries.
Came down here to type this. Add to your thumbs instead. DC boost is the key to mobile charging quickly without solar availability. Often will let you charge a "solar generator" Faster than any other means as the solar input has the most capacity. With a boost you're effectively making a "fake" solar array at whatever voltage. Just be sure not to exceed max input voltage of yer device. Boosting to 24v is reasonable and works on most things but if you've a specific device you want to charge REALLY fast it may be worth aiming for as close to max input voltage as you can. As a bonus if you boost near the battery you can use smaller gauge wire to wherever you device to be charged is as you're trading amps for volts and will get less line loss.
You beat me to it Jody.
Thank you, Mike, for the detailed response and the shout out! Greatly appreciated.
Also thanks to the helpful comments from others here in the comments. You all rock!
I sub to your channel also. You guys and Josh are great teachers. Thanks
Thank you! @@garywheeler2055
I found that wire at our local Rural King farm store ....its an invisible dog fence boundry wire...usually buried just below the surface ....sake yellow or red.
For Shane: a simple answer might be to buy a sine wave power inverter that plugs into your lighter socket, so you can use your regular LifePo4 battery charger. Just be sure the output is enough to support your charger.
naw. DC boost to 24v off the 12v and charge. Easy trick for faster charging on a lot of "solar generator" batteries. Just need to push that DC voltage up and doing that is way less lossy and expensive than DC-AC-DC.
I'm a joker.
I'm a smoker.
I'm a midnight choker.
Nice
Good demonstration of different power sources against different solar controllers.
Another great Video! Easy, nice, smooth, and to the point! Great work!
"He's chokin'!" ~ 8 Mile
The answer is never enough, you will reach a point where the impedance will plateau, but the coax will still pick up noise, so ideally every 5cm down the coax have a bead. But that will put induction currents in the coax.
The best is to choke at the tower and in the shack, then burry the coax from the tower to the shack, this way the burial will cut RF noise hitting the coax and only the exposed section on the tower will cop RF but if you choke it off good before the ground it will save heaps of noise.
The noise actually makes it's way past the shield, just like any thin shielding the RF will make the atoms bounce the RF inside the coax, this is why there is never a bottom to the DB scale, this noise multiplies internally along the coax causing noise floor increase on the sig wire.
This is not jacket leakage, say a 95% jacket, that will have direct openings that are even worse, it's the same, same, but I'm not talking about direct leakage. I'm specifically referring to solid shield penetration of RF which is measured at a DB scale.
1. Yeah, the controllers designed for "solar" sources are expecting higher voltages than the battery voltages, so they are all buck converters, whether MPPT or PWM, rather than having the capability of boosting the voltage. Depending on how you feel about ALI Express, you can get a cheap boost converter between the car's DC and the charge controller, but that's a project, and it may get hot. I've got that 3A mobile LiFePO4 unit, and it seems just perfect for the DenCo I bought for my KX3, with a specified 3A charge rate. It, of course, will work fine on bigger batteries, it will just take longer too charge them. But that's not a lack of efficiency. It just may or may not do what you need in the time that your have. It will reduce how long you have to charge at home. What's efficient is a mixed bag. You're using cheap wall power at home (or maybe even set up you panels, though it may have gotten dark), but if the energy to charge the battery uses (even a little) extra gas, that's a more expensive source. (Old EEs can't resist.)
2. What you can do at a park not only depends on the park, but also upon what ranger is on duty that day. Have a backup in the car, like a tripod and mast, or a mag loop, that you can use if they complain. Mike has demonstrated leaning the mast against a tree, in lieu of a through line, and they might complain less about that. But once you know that a particular park objects, don't do it next visit. (Don't be a richard.) Maybe POTA could arrange to accept activator notes that they could decide to add to their park data?
Meow?
great video. very good questions ! I go with their is no dumb questions ever. the best thing I fount is for part rules is simple. JUST ASK THEM ! don't be shy. find park ranger or someone . I find letting them know what we are doing and how we clean up . they nicely give up the answer . I even got a permits do a long wire at state land to do 160 meters. all just buy asking. in fact the park ranger took his lunch break with me. even showed him the parks on the air rules. was a great time . as for charging LiFePo4 from a car use a DC to DC charger. powerworkx has a 8Amp one. has power poles right on them. Victron and renogy has on. can set max amps. like 15 or 20 even 10 . have to hard wire put power poles on them. with 12V lighter port use 10 amp max. that why I use the powerworx 8 amp one. I have 20 Ah LifePo4 and 8amp charge does not take long. 73's
Thanks Mike great information!!!
For the last question: they could always call and ask. Of the people I know who do POTA activations, none had any issues provided the park knows about it. They usually call them up to let the park know what they are doing anyway and just want to get a low-down on what's acceptable or not. Some parks will ask questions, but if educated, they'll usually have no issues.
A rule of thumb is in historic sites, I would be careful with things in trees. We have one in Georgia, Fort Pulaski that doesn't allow anything in trees or in the ground. SO a mast (hitch or drive on mount) and then something like a chair or attach the end to the BBQ grill.
Probably because Fort Pulaski isn't a Ga. state park! Its under the National Parks Service, and is a National Historic monument. If they did allow any one to hang a rope, or drive a nail. Our nations people would destroy it, in a matter of time! Just like that dumb ass guy was carving his initials into the Coloseum in Rome, Italy! People are stupid creatures, and don't care about preserving history or nature!
Parks in Nevada do not allow anything poked into the ground. So no Chameleon ground spikes, tent stakes to hold radials, etc. Tripods for Wolf River verticals (or Chameleon Tactical Delta Loop!) and radials laid out with rocks holding them in place are how we POTA. Can't answer for trees; we mostly have cactus.
Great video Mike ! Keep up the great work 😀😀😀
Never had a problem in a national forest with using a tree but national monuments are fairly strict. State parks are subject to the the state and the ranger on duty. Best to get a pushup mast and avoid the problem.
Steve, k7ofg.
After reading that title combined with the thumbnail image I thought I was getting a Radio/BJJ mashup.
I use a 300w(30vx10a)residential solar module with a mppt charge controller to keep the RV lead acid batteries topped off for 2 years now with no issues.
Get a DC to DC charge controller from renorgy. You can get DC to DC only or get a duel input that will use solar or alternator. But easiest probably just get a pure sign wave inverter and get it hooked up in vehicle weather through cigarette lighter or wired up to battery.
There are bigger lifepo4 charge controllers for "12v" automotive, like renogy 20A DC to DC On-Board Battery Charger. It will take alternator voltage and charge your battery. I would suggest a relay so the controller only comes on when the vehicle is running.
On the POTA question. Almost certainly if there is a problem they will just tell you to take it down. If you really really have to know in advance I would call the individual park office. I'm like Mike. I would rather ask for forgiveness after.
Decreased input voltage means decreased input current, therefor your charger output current will be decreased, basic Ohm's law. V=IXR where the resistance is your battery, yes the cells have resistance, and it increases with cycles and your capacity decreases as it increases, this is why lithium cells seem like they don't hold a charge as they age, they really don't.
All the chokes! Also love the shirt!
Strictly for trolling purposes of course
New Ham here. I got my FCC Tech lic here in Japan KD9VUL (I'm stationed here). I now also have a Japanese ham lic JK1VCF. I know I have to use my Japanese call sign here in Japan but besides using a paper log book is there any way to merge the data when I go back to the States? Thank for all that answer
Hi Ginger. I would recommend downloading and using a logging software as soon as possible to make your life easier. Enter in any contacts you have now and keep adding them as you make them. If you only care about the actual data you can just keep adding more contacts to the same log when you get back to the states, or you can simply make separate files for JA and USA. If you care about Logbook of the World you can still use the same log, you just need to use the TQSL program that is part of LOTW (a separate program though) and set the dates for when you are in JA and when you are in the States. I did a video last year showing how to do that. czcams.com/video/VfL5sGWDIY4/video.htmlsi=q2CUOZMOadvEDjm5 Keep in mind, this isn't a video on how to get setup with LOTW in general, you'll need to go through that process first, which is quite the nightmare to be honest. But once you are, this is how to add another location. Once you have multiple locations in TQSL/LOTW, it will keep them separate. Hopefully that makes sense.
For coax chokes do I want to choke both ends or is one sufficient? If one, should it be radio side or antenna feed point side?
Did you forget to flip the switch for the MPPT controllers? Why would they all do nothing?
14:00 Leave no trace seems to be a good starting point for thinking about how to get wire in the air
I expect that historic parks, especially those that have anything to do with Native Americans or battlefields are the places a person should consider asking permission rather than seeking forgiveness - or maybe just do the activation entirely within the confines of the vehicle.
Mike, your tests on the solar charge controllers brings up New questions! Why don't these all work? 12 -13 VDC is 12 -13 VDC! Was the incoming voltage to low? Or the amperage to low? Or Both?
Or was your battery just FULL?
Would they work on a SLA battery?
🤔
I suspect the input voltage was too low for the MPPT. Some of these will work on SLA. The Bateria and Bioenno will, but not the others. They are just for LiFePO4.
Hey Mike, would be cool to see you doing a video on "tiger tails" for HTs. I've been messing with this recently, but would love to see your input.
No sir. That’s not an antenna, it’s a wire hammock
haha!
I got some Not A Rubicon vibes from that beginning of the video 😄
He is my hero. I just wish I could pass the GMRS test lol!
@@hamradiotube 🤣
The little red charge controller? Need some information about it. I have a small battery project I am working on, and it might be perfect for my project. Thanks in advance.
OK, Mike, here is a question for mailbag Monday: I have a G90 and live about 1/2 mile from a commercialAM broadcast transmitter. I get bad RFI when they are transmitting on most bands. I built one of K9DP's AM broadcast filter kits, and it helps somewhat, but I am still getting interference from the AM radio station. Anything else I can do?
That's a tough one and one I don't have experience with fortunately. I wonder if a receive loop antenna might help??
Move. I know that is gonna sound crazy but you're just right up against a BIG transmitter here. G90 is small and portable, great for POTA/SOTA. You could spend $$$$ trying to ground everything and Choke and bandpass your way out of this or just operate elsewhere. That said, do make sure you have the basics of solid station grounding and choking delt with. So many small desktop "hamshacks" I've seen with unchoked/ungrounded setups wondering why they're deaf.
@@chublez Thanks for this info. I actually have NOT done any station grounding or choking. I dont know if Mikey has a video on that, but if you could point me in the direction of resources, that would be great. The AM station reduces its power at night, so it isn't quite so bad then.
Can I get a link for the mini shrinkwrapped charge control thats so noisy? You said in another video it wont run a battery down when its not charging.
It's this one right here. Make sure to select 4S LiFePO4 www.ebay.com/itm/184903276670?_trkparms=amclksrc%3DITM%26aid%3D777008%26algo%3DPERSONAL.TOPIC%26ao%3D1%26asc%3D20230811123856%26meid%3D9a0c0eea63254738bec6fe4369b30a8b%26pid%3D101770%26rk%3D1%26rkt%3D1%26itm%3D184903276670%26pmt%3D0%26noa%3D1%26pg%3D4375194%26algv%3DRecentlyViewedItemsV2%26brand%3DUnbranded&_trksid=p4375194.c101770.m4236&_trkparms=parentrq%3Aa9f0b95818a0a5140c9d25f2fffff83c%7Cpageci%3A5ee21d30-5660-11ee-8a8a-2e1251eb7f8e%7Ciid%3A1%7Cvlpname%3Avlp_homepage
Thanks much... RFI here I come.@@hamradiotube
I know you not a low bander but if a low bander wanted to stop his common mode currents on the lower bands he could purchase a Amidom K mix core I think 240 is the biggest they make but it has by itself 1 core up to 7500 ohms of block capability. Well that’s where my fried equipment stopped it may be better. We use 4 of them in place of the oem stock palstar balun that is at 500ohms. We use 12-14 wraps or rg 400 to get the spec quoted above 😊 Google mongo balun article
What are the symptoms of needing a choke?
hello Mike, Peter here thanks for all your videos. I have a question for you, how safe are you from antenna rf when mobile being so close to the antenna. I,m a newbie studying for my ham licence the goal being the intermediate. I have seen many hams with a portable antenna stystem blasting away at 100 watts sitting only a few feet away in there car.
Pretty darn safe. The ARRL has an RF exposure calculator you can use to tell you the minimum safe distance. www.arrl.org/rf-exposure-calculator
@@hamradiotube thanks for getting back to me so soon much appreciated 👍 best wishes 73s
I bought a coax choke from ABR and the discount code did not work, stated expired.
Another great video Mike! The first thing I thought when the video started is... what is in the box? lol hopefully more ham goodies. 73 KD5YOU
Hi Mike, love the channel, I tried to buy a chock cable at ABR and they only serve the United States.
Since I live in Canada, there are no way to buy it or delivered.
Just something to know when you promote ARB company.
VE2HRJ
Mike, LOVE your content and sense of humor. It looks like you ABR Industries discount code expired already. Was is supposed to be that quick? Keep rockin!
Frank/W3FAC…. And fellow musician(Bass player).
Hmm, it doesn't expire so that's weird. Maybe give them a call??
@hamradiotube Hey Mike. I had the same problem. Also I called them today and when I selected 0 for operator, it went to VM and no one returned the call. Are they still in business? Would you recommend another vendor? Thanks as always. 73.
73 of PY1PC
ABC
always be choking