Discussion in 'QRP Corner' started by N1RVN, Feb 6, 2017.
Here's a photo:
Sorry for the late reply... I get a good four hours of operation out of each the 6Ah batteries. SSB at full 100 watts, estimated RX/TX ratio 80/20.
Has anyone tried using 8 alkaline D cells?
I've operated my FT-817nd off of 8 high-output AA cells. These were 2.5 AH Eneloop Pro rechargeable NiMH's (the black ones), and things ran well for about 2 hours on a mix of digital, SSB with a speech compressor, and FM. Regular 2 AH Eneloops (the white ones) barely lasted a half hour. I doubt that conventional alkaline AA's would do any better.
I know you asked about D cells, but after several days' wait and no answers, this is as close as I can add anything to.
Alkaline D cells are kinda pricey considering they are not reusable batteries.
8 throw away D cells will run you about 1/2 the cost toward purchasing a LiFePO4 battery pack that can be recharged 2,000 to 3,000 times.
I was just thinking of using D cells emergency back up. I've purchased a battery holder on eBay. When it comes I'll try it and report my findings.
Food for thought men, I didn't read every reply here all the way through so this may have been mentioned. I too own an 891 (love it) and there are some fairly new you tube videos out and one gentlemen did a real good test of the current draws at different power outputs. Max at 100 watt is only 15.2 amps... Receive draw is .9-1.03 amps, TX power at 5 watts 5.6-5.7 amps, 10 watts 6.9 amps, 20w 8.3 amps, 30 watts 9.3 amps, 40 watts 10.4 amps, 50 watts 11.5 amps. I didn't write down the rest of them but that gives you guys a good idea who want to run this radio portable.
I was running a 10ah Lifepo4 battery. It worked, but 100w transmit was limited to less than 30 minutes or so of hunt/peck ssb calling and answering. I saved a lot of power by running at 20w to 50w, and didn't lose much signal.
If I had to do it again, I'd probably go with a 15 to 20Ah battery for a 100w rig.
Mine 22Ah was lasting 5 hours at 80W in field day/contest style of operation.