Nice setup! I would like to make something simular for my FT857D. Did you get the dimensions from a link, or all DIY? All Alu? Keep those vid's coming. 73, ON3SVY.
Eduardo Power it looks like he had 18650 lithium polymer cells in 3S8P. I can't estimate the current draw but in 8P the max current the battery pack is capable of is quite high. In 3 series the nominal voltage is 3 x 3.7 = 11.1 volts. The maximum voltage when fully charged is 3 x 4.2 = 12.6 volts.
Is that a THREE cell Li-Poly battery, at 12.6 volts maximum charge?? -If so. it will rapidly fall BELOW the voltage required for proper FT-857 transmit operation. (Voltages above 12.5 but not exceeding 15.5 are ideal)-4 cell series LiFePO4 would be good, but 4 cell series Li-Poly at 16.8 is excessively high right after charging.--Please explain the battery, and actual operating voltage, as measured during transmit.--Below 12.0 volts, 3rd order transmit IMD increases noticeably, and frequency stability/audio quality during SSB transmit may suffer. (Receive is typically OK, down to about 11 volts.)
I was thinking the same thing so I did a super quick price out in my head for a lifepo4 pack. The first cheap (mah/$ value) were 1500mAh cells for 3.75 each. To get the same Ah capacity he would have to run 18 cells in parallel. As you mentioned the pack would be 4 series. That equates to 72 cells. That's $270. Ouch. His 3400 mAh cells are around $6 at the volume of 24 cells. $144 in cells. Nearly half. However not only the issues you mentioned come into play but the total energy stored ignoring those issues. His pack is 27.2 Ah at 11.1 volts nominal makes for 301.92 watt hours. At nearly the same capacity of 27 Ah (18 x 1500mAh) with a nominal voltage of 12.8 give 345.6 watt hours. For the same amount of energy (~300 watt hours) you would need ~24 Ah. This drops you to 16 parallel for 64 cells total. This drops the cell cost to $240. Pros: better radio performance, longer battery life (higher useful cycle count), safer cells (LiFePo4 dont tend to ignite when punctured), better compatibility with all 12v equipment Cons: larger, heavier, more expensive, LiFePo4 hardware (ie charging) is less common If nothing else the issues you pointed out with xmit warrant LiFePo4 use
#1. What? A video with no freaky weird RU-vid music / noise? Actual real talent behind instruments? NICE! 👍 #2. If that's a backpack then how much does it weigh? That looks to me to be 40#s minimum. Shoulder straps? #3. Pack or not, that is an awesome setup. This would make any amateur envious. My current setup consists of one uv-5r and a cooler of snacks. One day I will be cool also. Ko4emh
way too complicated! 12Ah LiFePO4 battery, Yaesu FT-891, EFHW resonalnt antenna for band of your choice (I ususally have a 20 meter antenna), some cordage, (doubles as throw line) a short length of good quality RG 58 coax. All fits into a small back pack. Enough room for sandwiches and beer, pencil and paper. Good to go.
Frank Zappa I think you (totally) missed the point. I do it your way, but we have to fix it all together when we get there. This guy has it sorted before he even starts to walk. Les
Would have been nice if you would talk instead of playing sleep music. You obviously like to talk since your a ham operator. I would have loved to know what the pieces were, where you found them, etc. Such a shame it could have been Great!
Tom B But likely English is not his first language, so then he’d get stick that his accent obscured what he was saying, couldn’t hear properly, etc. He did it his way. You’re a free to do it your way. Do you have videos on this topic? Can I watch them and listen to them? Les
