Garmin etrex H on 12V

[Trevor Wright]

Does anyone with a Garmin etrex family GPS unit run it from a car 12V supply?

With the cable I've got, which doubles as the PC connection, there is no indication as to whether you need to remove the alkaline/rechargeable batteries when running on 12V.

I'm guessing the etrex does NOT act as a battery charger and so when on 12V the internal batteries are isolated, and so can remain in place safely - but has anyone a definitive answer on this?

Thanks

[Trevor Wright]

Answered my own question in fact.

If you start your eTrex in what I'll call "Test Mode" i.e. hold down the top buttons either side and press the power/ON button, it shows your internal battery voltage. When it gets power from the car 12V cigarette lighter socket it shows the external power as just under 3V. When the engine is running it shows just over 3V. At no time does the internal and external battery voltages show together and the eTrex switches back and forth between internal and external.

Just for the record, the 12V supply will NOT act as a battery charger if you are using internal rechargeable batteries.

I purchased my combined serial PC/12V cable via eBay and was of "Gilsson" manufacture, and seems very well made, and is a lot cheaper than the Garmin item.

Hope this info is of some assistance.