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eHam Forums => QRP => Topic started by: LB1RI on February 08, 2019, 12:22:47 PM



Title: Yaesu FT-818ND power output on battery
Post by: LB1RI on February 08, 2019, 12:22:47 PM
Hi! I bought myself a Yaesu FT-818ND a while ago. I like the radio but can’t figure out of this power limit when it runs on the internal battery. Has anyone measured the output power on this unit? The manual says the power is automatically limited, but mentions nothing about whether it can be overridden or not. So I figured it can’t. Online I’ve seen some say it still can output the six watts, but not how. When I select the output power while running on internal battery, the indicator flashes at the points when the transceiver would output 6 or 5 watts. I don’t have a power meter to measure low power precisely. Has anyone else done so, or can anyone point me in any direction?


Title: RE: Yaesu FT-818ND power output on battery
Post by: KB1GMX on February 15, 2019, 06:51:44 PM
Power limit is dependent on battery condition and likely fully charged its the stated 6W.
However he power drain is  high enough that will not be sustained for more than a few
minutes at that point it falls back to half power.

From everyone that has one its almost exactly the same as 817 save for that one its
5W not that 1 watt makes that much difference.

IF you want to run full power for more than a brief time use an external battery.

Allison


Title: RE: Yaesu FT-818ND power output on battery
Post by: N3PM on February 16, 2019, 07:16:31 PM
 FT 818 with SBR32mh battery @ 9.9V key up - OHR WM-2
Highest power (shows L and 2 bars and flashes) -    7 watts     8 bars on the display
High power  (also shows L and 2 bars and flashes) - 6 watts     8 bars on the display
Medium power (shows L and 2 bars not flashing)  -   3 watts    3 bars on the display
Low power  (shows L and 1 bar not flashing)      -    1 watt      3 bars on the display
Contrary to the manual, mine never shows L and 3 bars, nor does it default to 2.5 watts when powered up
while on the internal battery.
However, it does all four iterations of the L and bar display when powered by a supply or external battery.
MIke N3PM


Title: RE: Yaesu FT-818ND power output on battery
Post by: N0YG on February 25, 2019, 06:31:22 AM
I have the FT-818ND and on the very first page, PAGE 1, it covers all the power setting in the first paragraph. battery power vs power supply and their power levels. Hope this helps and stops all the myths. I know the original question was " how to override the battery or portable power levels". It says in the paragraph that the power level "automatically" switches to 2.5 watts on battery. My answer is " I don't know or if it can be done ". Call Yaesu seems to be the easiest answer. Anyway good luck!


Title: RE: Yaesu FT-818ND power output on battery
Post by: LB1RI on June 17, 2019, 12:56:50 AM
Thank you all for replying, and NP3M for the measurements. Just what I was after. :)

The manual and the power indicator together with the bar graph in the display are confusing. The manual doesn’t correspond with my display either. The fact that the indicator is different between internal and external power makes it even more confusing. But now I know it gives full power even on internal battery.

(P.s. Sorry for the late reply.)


Title: RE: Yaesu FT-818ND power output on battery
Post by: N2DTS on June 17, 2019, 08:50:02 AM
On my 818, the power output on the built in battery was much lower then the 6 watts on 14 volts.
2.5 watts seems about right.
The built in battery is not going to last long even at that power level.
Its a bit of a hog on RX...


Title: RE: Yaesu FT-818ND power output on battery
Post by: OZ1DTF on June 22, 2019, 04:09:50 AM
Yaesu has made an attempt to describe the power states pedagogically on page 25. By the way …. my first problem after unboxing my FT-818ND was that I read in the manual that a triangle is displayed to the right of the parameter e.g. IPO. It turned out that it is to the left! This error is consistent throughout the manual. Has this error been in the manual for decades since FT-817 was born?