I have a small voltmeter that I will be fitting to the 3d printed case I am making for the LiPo…I don’t trust myself to keep checking the voltage from the 818s menu system while in use.
Use a battery alarm as designed for radio control use - it is connected to the charging/balancing connector. You can set the threshold voltage for each cell and the alarm would wake the dead (mine went off in the bedroom at 0300 - her indoors was less than amused )
This is a lot more than I paid but that was years back. As Barry suggests, VERY loud.
That is for 10 Rod, 83p each 73
just in case anybody was curious about that kind of battery (motorbike batt) I will add some info here.
I was intrigued by such batteries and bought one myself about two years ago:
Info was vague and imprecise, as the vendors are not experts of battery chemistry.
The labels in the part are itself confusing; it says Lithium Ion.
One could think it is a LiIon but it is not; after some research I confirmed this part is LiFePO4, 4S model.
In the advert they announced it as of a 7 Ah batt, but after a charge from low voltage level it was fully loaded with about 2500 mAmp, that it fact matched well with its weight.
A real 7 Ah batt should weight more than double.
In addition, the robust and massive package adds redundant weight, because in the end it is designed for the environment of a motorbike.
So, what? It works well, and although it is not (too) expensive, it is better to use a LiPo for the FT818, as others suggested. I used a 3S Lipo 2200 mAH and works perfect for several years up in the mountains.
The battery I bought still works fine and I use it every now and then but when it becomes old I won’t mind saying goodbye without buying another one.
73 de Ignacio
Batt dimensions: 15 x 8 x 9,5 cm
Weight about 550 gram
The battery alarm is a great tip, I had not realised that such devices existed. I have just ordered one.
Also good to see the feedback on the motorcycle battery