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This afternoon I was making some measurements to try to determine the current consumption of the VX-8G (and hence estimate the battery life) and I stumbled across a rather serious flaw. When the internal GPS is enabled it remains powered all the time, even when the radio is switched off. Enabling the GPS causes the current consumption to increase by about 30mA, and that same increase is noticeable in the current drawn when the radio is powered from the external DC socket, whether or not it is charging. This level of current drain would flatten the 1100mAH battery pack in less than two days!

I joined the Yahoo VX-8R group, which is the discussion group for the VX-8G as well, and noticed that some American purchasers of the radio had already discovered this problem. I hadn’t had the radio go flat on the shelf myself, mainly because in the three days since I got it I have been using it quite a lot. But my observation does help to explain why I found the battery life was poor. Like most people I suspect I have been charging it up after an outing and then taking it out of the charger in the expectation that it would still be fully charged the next time I used it. But with 30mA being taken from the battery all the time, even a 12 hour period off-charge would result in a significant loss of operating time.

The VX-8G isn’t yet available in the UK so there is not much point in contacting Yaesu UK for their comments on this issue. It’s possible that when the European VX-8GE version arrives Yaesu will have identified the problem and fixed it. If I was reading this and thinking about getting a VX-8G I’d certainly want to receive an assurance that the fault had been fixed before buying one. And if I’d bought this from a UK dealer I would probably be taking it back. So this is really an example of where buying from Hong Kong hasn’t paid off, even though the problem isn’t the fault of the dealer who sold the radio.

The workarounds would appear to be either to turn the GPS power off from the menu whenever you switch the radio off – a real hassle which will probably result in the GPS taking minutes to get a fix each time it is switched on – or else to leave it on charge all the time. The latter would seem to be the least painful.

It is a pretty annoying fault to be stuck with. I had been thinking about getting the high capacity battery pack but having found this problem I don’t think the VX-8GR will be a keeper. I shall look with renewed interest at the Kenwood TH-D72 APRS handheld when it becomes available, though I shall probably lose a lot on the exchange – giving publicity to this fault isn’t exactly going to help the VX-8GR’s resale value. 🙁

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