Anyone use low voltage alarms?

Once I get a pileup and get into the flow, the contacts are all I am interested in. I have a feeling I ran my battery down quite low on it’s first outing (way to go Steve) so am thinking of a low voltage alarm like this one:

Do people use these, and is that the right/best sort for my LifePo4 4S2P batteries?

If your pack is greater then 5Ah with 100W I really wouldn’t even consider it being a problem, even for multiple activation’s. If in doubt do the maths.

If you are worried plug your LiPo charger in the multi-cell connector to monitor it.


I have an inline meter to measure the Ah used, and the rig displays it’s working voltage, but you have to look at both. That’s the issue. I’m thinking a buzzer to say “Oi you muppet stop running me flat” would be good.

It should be a non issue really I suppose as my plan on multi summit activation days was to alternate my two batteries on each summit. I averaged about 2Ah per summit, and was budgeting to allow 6Ah use from one of my 8.4Ah batteries. On my single activation so far though I only had one (fairly) fully charged battery.

It is a non issue.

I have such an item. Waste of money. It bleeps away on peaks of RF and is loud and annoying. If it was accurate I have been abusing a pair of LiPos since 2010 with no apparent detriment to the batteries. It stays in the shack now and is one less thing to carry there and back. One less thing to fail.


cheers. I couldn’t be doing with that then, it would do me swede in, and it would have an appointment with the guy peg hammer…

Not really, because the steady state voltage is proportional to the charge used in the battery.


I meant to check either (rather than both I should have said) you have to actually look at what they are displaying.
When I am tryng to check signal received, remember the call long enough to write it in the correct order, note the time on my invisible to see in the sun phone (soon to be fixed by my old contest clock), I forget to look at either.

Hi Steve,
Just joining the concensus here - yes have two of these units (or very similar ones) on my two 5000maH LIPO batteries. After the first couple of activations, I disconnected them and there in my bag “somewhere”.

You really don’t need them unless you are planning a really long activation - camping overnight or the like.

73 Ed.

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Wait until you try and activate in a 28mph blizzard in Winter Snowdonia, then you will have difficulty holding onto anything :wink: I am sure we don’t have it anywhere near as bad as say Canada though.



I have been blown literally off my feet in the col between Tryfan and Glyder Fawr. As it was windy as heck we abandoned plans to do tryfan and bristly ridge and walked around Tryfan instead. One second we were minding our own business battling against the wind, next second two of us were 10 foot away and down a bank a bit. I have no recollection of flying either. We just teleported to a new place.
So I am always respectful of the wind.
I’ve even had to resort to hands and knees once on Skirrid, which is a ‘friendly’ mountain. The ridge runs 90° to the prevailing wind and it funnels all the air up to the ridge I believe.
I’ve carried on and completed the route from Storey Arms to Pen-Y-Fan one winter when everyone coming down was telling us to turn back like they had to at the col just before Corn Du, so I’m not adverse to a bit of bracing fresh air.

I average 200mAh per activation.
I’ve just topped up my LiPo from yesterday’s 3 activations, and it needed 510mA in total (average of 170mAh per session, only 75 QSOs in total)).
Just as well I took the 1000mAh pack rather than the normal 350mAh :smile:
I budget for 3mAh per contact to give me some leeway.


That’s pretty lightweight! Are you using CW?
Mine is >600mAh per hour if I don’t transmit :smile:

I could cut that down using the 817 of course, but I have chunky batteries now and my 150w charger came today!

Heavyweight in comparison to the PP3 challenge guys!
Yes CW.

That’s awesome!