AR Cover - EMR exposure

[VK3YE]

Only in America...

[VK3ALB]

Must be true he has a business card with hand written details on the back.

[VK4GHZ]

Only in America...

Yep!

Hard not to notice the YAESU badge on this guy.
Redefining what YAESU stands for?

Your
Always
Endangered
Standing
Upclose

[VK2NR]

Let's see how quickly the backpack comes off when the battery pack suffers a thermal runaway event!

[VK2OMD]

Let's see how quickly the backpack comes off when the battery pack suffers a thermal runaway event!

I have run a 100W ssB radio off a 4Ah 4S 25C Life battery (about 300g) in a normal contact for a quarter hour and it used about 2/3 of the charge. Peak current of 18A was just 18% of the battery peak discharge rating.

To assemble a battery pack for say 48V to power a 1kW out amplifier at peak current of say 40A, could be easily done with a pair of 1Ah 6S 40C Lipo, that you wont get much operating time, More practically, a pair of 5Ah 6S 20C will sustain 100A peaks, probably sustain more than a half hour of operating the PA, weigh just 1.5kg, and cost just under $1000. LiFe batteries are a little more expensive, and safer... but LiPo would be fine for a demonstration.

I doubt that powering such an amplifier is a challenge as suggested, buy it is a silly idea for other reasons! About as negligent as people one hears of running 400W or more to a small indoor antenna.

As far as risk of fire etc, yep LiPo batteries have risks but they are widely used in mobile phones, cameras, UAVs of all types, and even the largest jet aircraft (albeit with some teething troubles). Better not use a mobile phone if you don't trust LiPo.

Lots of people use LiPos, and they don't need a bomb proof bunke to charge, store and use them! However, selection of a battery appropriate to an application might challenge some folk.

Here is a data logger capture of an IC7000 running 100W with compression off. I have talked as loud and consistently as I could, so it is an OVERESTIMATE of consumption. Note too, that like many Icom radios, the IC7000 draws a relatively high current key down with no audio (4.5A here).

Click on it for a bigger pic. 0.102Ah was used in 1min, so a 4Ah battery might last more than half an hour transmitting all the time, longer with intermittent transmitting. Peak current rating on a 4Ah 25C battery is 100A, no issue for the 15A peak experienced.


Owen