Time to look at battery options

Apologies for no HF today from G/NP-029 Sharp Haw. I was really looking forward to it. I took a couple of EFHW antennas for 20M & 10M. Got set up fine using a fence post to support my fishing pole so the middle of the antenna was well elevated, tied the far end of the antenna to another fence post and had the end nearest to me clear of the ground too. All looked well and upon switching on the 817 the 20M band sounded in good shape. Found a clear frequency, keyed up to tune the antenna and the 817 switched off. At first I put it down to an RF issue so I tried again, same thing happened. Dropped the antenna and changed it for my 10M EFHW, same thing happened. Messed with the antenna, even tried 15M but again the 817 switched off. I charged the internal battery in the 817 overnight for 8 hours as I have always done and this was activation number 62 and the first time I had this problem.
Packed my gear away and by now Ian G6OVR/P who was with me qualified the summit on 2M FM. Asked politely if I could use his yagi on 2M SSB to try and qualify the summit. His yagi is obviously resonant and when connected to my radio guess what happened when I keyed the microphone? Yep, 817 switched off. Thankfully Ian let me use his radio and a nice QSO with Don G0RQL gave me my fourth contact and qualified the summit for me. Lesson learned, always take my handheld on activations as a back up just in case! Had I been alone as I often am I would have been snookered.

Sorry again for no HF, but there will be other times. On the plus side, Ian and I ascended G/NP-029 from Bog Lane, my previous activations of this hill have always been ascended from Flasby.

73 Chris M0RSF

As far as SOTA is concerned I’ve always treated the 817 internal battery as the backup and used an external one as the primary power source.

No need for apologies Chris these things happen,do take the handy as a back up. 2mtr ssb activations are getting as rare as hens teath.Glad to oblige with 2ssb. 73 Don.

I hear you Don, and I will do something about it.

Tuesday night, I will do a long (over two hours) activation, and it will all be on 144MHz SSB.

Look forward to working you.

Likewise. So it is usually stupid mistakes that terminate my efforts.


[quote=“M0JLA, post:5, topic:9807”]stupid mistakes that terminate my efforts[/quote]Got (or, possibly, torn) that t-shirt…

Battery? Ah, yes, I remember. I put it on the charger for a last-minute top-up…
Adapter? Well, here’s a BNC plug and an SO239 socket, but no PL259 to BNC thing…
Microphone? Oops, it’s hanging on its hook in the shack the other side of 22 miles of water…

73, Rick M0LEP – Checklist? Knew I’d forgotten something… :wink:

Sorry to hear about your problems with the FT-817 internal battery. Seems one cell has died of high internal resistance.
I try to avoid at least some of the common pitfalls:
Two separate LiPo batteries of 4 Ah. One charged just before activation the other one used and charged from time to time. The second one is not required in regular activations.
Two battery cables for the FT-817 just in case one fails.
The FT-817 internal battery pack is always installed but poorly maintained, so not a real backup. As the internal battery of the FT-817 does not suffice for the full 5 W output I always use external batteries and do not care too much about the internal one.

As I use my handheld for APRS I always carry it with me. So in case the FT-817 fails or I have forgotten the microphone at least I can do 2m/70cm FM.

73 de Michael, DB7MM

Sorry to hear of your troubles Chris
I have used the inernal battery once having had a similar experience and now switched to a tracer battery.
I now store some spares inside the battery compartment instead of the battery;

  • spare fuses.
  • spare dc plug with power poles fitted.
  • Choc block
  • BNC plug with screw terminals.


I had that happen to me with a brand new pack. I split the pack up and now use the remaining 7 AA cells to run my handheld. I never did get around to replacing the pack and now always run from my external battery pack without any backup. Somewhat risky yes, but it would be a rare event if the 2 x 4AH LiPOs failed!

Will be up in GM/SS at the end of the month Don. Sorry we’ve had a 4 month gap from the last GM outing, but a number of issues have kept us off the hills. Will be out on Saturday “training” in GW/MW using the “B” calls, in my case running 70cms SSB (40W to an 8 el), so a bit more of a challenge for you there. :wink:

73, Gerald G4OIG

Recharged the internal battery last night and it seems it’s shot. Tried it in both my 817’s (rules out radio fault) and into a Dummy Load my SWR/Power meter only showed half a watt and the radio switched off. I have a new, never used original Yaesu battery that I got with my new 817 but I’m tempted by these as recommended to me by Nigel G0NIG …


I don’t spend a massive amount of time on summits. Any thoughts?

73 Chris M0RSF

Hi Chris
I bought my FT817 a couple of years ago, and it came with the NiMH battery pack. I generally use a small external SLAB, but for longer walks I just use the internal battery. I have found that it easily covers two consecutive activations of 30 minutes to 1 Hour or so, using a mix of 2m FM and HF CW. I have also used it set to 5Watts o/p, though usually 2.5Watts is enough to qualify a summit.
I often use headphones too, they are quite a battery saver - loud audio takes power.

Many people dismiss the internal battery, and certainly it isn’t up to a full days operating, but I find that it has a useful part to play.


Likewise Adrian, I’ve found the internal battery fine for a couple of activations in the day. I did Great Whernside the Buckden Pike a couple of years ago and still had battery power left.

73 Chris M0RSF

Don’t dismiss the internal battery pack. Use the pack that comes with the rig designed to hold alkaline cells and use some really good NiMH AA cells in their place. If you cut the green wire going to the plug you will be able to charge the cells in-situ as well. I use this with a LI-Ion battery as the main standby and it will usually do at least one summit and sometimes two depending on how much gossiping goes on.
I only use SSB and CW, never FM, with the 817 so this does help capacity.


Barry GM4TOE

Has anyone any used a pack of 18650 Ultrafire batteries to power an activation radio? A pack of 3 or 4 with 5000mah to 6000mah is pocket sized. I don’t know what the power delivery characteristics would be. Are there any issues or negatives with them? Am I missing something?

I have. The capacity ratings are rather suspect on many of these cells. Apart from that, no issues.

I have some packs made up from 18650 LiIon cells I got at a rally. They were £1 each but I persuaded the guy to do 6 for £5 so I could make up “12V” packs. Mine are 2200mAHr and I’ve used them in foreign places to power the 817 or my VX170. I’ve got them on a plane! The internal resistance is higher than LiPo so they sag on full load a little but work fine.


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Blimey Andy… I’m surprised you managed to get THAT on a plane. They look like explosives!

Don, this year I’ll be doing much more 2m ssb.

Chris, I’m using 4s lipos now with a diode voltage reducer, feel free to email me should you want details.

Best 73,


As I plan to take part in the Practical Wireless contest this weekend I’ve decided to purchase a SLAB. I’m undecided on a 2.1 Ah or the slightly heavier 4 Ah.

Is the 4Ah worth the extra weight in the rucksack?

73 Chris M0RSF


I don’t know what rig you will use so the answer is Dunno.

If you are unsure take the biggest you can carry. Extra run time!

I used to carry a 7 AH gelcel to a peak with my IC706, al mast and 2 m and 70 cm yagis, coax etc and could just get an hour on air before the battery volts went too low for the TX to operate properly. Recharge and back the next morning every day for a week every summer for nearly 10 years. Went through a few batteries.

Now I’m looking at an LNR in one pocket and a 2 AH LiFePo battery in the other. Total station weight has to be sub kg.



“Brands” like UltraFire and other similar-sounding names are widely regarded with suspicion. I have read claims that they can be recycled cells from laptop packs, with a shiny new label applied. The capacity claims are, shall we say, optimistic (I think the most any Japanese brands claim is about 3Ah - I guess that’s the limit of the chemistry). For comparison I have some Sanyo 18650 cells and, despite a lower claimed capacity, they hold up a lot longer (at least x2) than the UltaFires. But then again they’re dead cheap and will run the FT-817 for a couple of activations for me.


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