After operating my Yaesu FT-818ND for several days, I noticed that even though the backlight was set to auto in menu option 10. The backlight was never actually turning off.
Thinking it may have been the mod that allows the radio to TX on 60m (yes, I have a sub-licence for 60m so am allowed it) I reversed the mod to confirm this.
Nope, wasn't the mod. Even with the radio as factory default, the backlight still never turned off. So I re-implemented the modification to allow the radio to TX on 60m.
After several hours of stumbling around the internet and not finding a lot of information regarding this undocumented feature.
I figured out it was due to the plug being in the DC power barrel socket.
I have an Anderson Power Pole adapter attached to the radio, and even though there is no power going to the adapter and I was running on internal battery, the radio knows there is a plug in the back.
Unplugging the Powerpole adapter and the Backlight Auto off function works as described.
Seems Yaesu in their infinite wisdom seem to think if there is a plug in the back you always want the back light on.
I'm going to start interrogating the DC socket to see if I can disable the "switch" that seems to permanently enable the backlight and ignore the settings of menu option 10.
I'll post an update once I get some time to have a play.
For now though, If you have a power pole adapter on the back of your FT-818/818ND you will find the backlight never turns off. So you may want to disable the backlight in menu option 10 to conserve battery power.
I'm not sure why they didn't carry this option through to the newer models, but Yaesu had the best solution in the FT-897D.
On my 897D I have the option to turn off the backlight completely, turn it on so it's always on. Alternatively I have two options for Auto Off.
AUTO1 turns off the backlight after 3 seconds no matter how the radio is powered. This one turns the backlight off even if there is power going to the DC socket.
AUTO2 turns off the backlight after 3 seconds if it's running from internal battery power. This option leaves the backlight on if there is power going to the DC power socket on the back of the radio.
To me, it would have made sense for Yaesu to include a similar setup on the FT-818 series radio aswell, Just because I'm running on power, does not mean I want the backlight to always remain on.
Come on Yaesu, if this is a simple firmware fix please fix this on the FT-818(ND).
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