HF Transceiver Power Consumption - What Am I Missing?

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Working on studying for my General and looking at HF rigs for the fun of it. I would like to be able to run occasionally portable off battery power from near my RV or truck (not looking to hike a mountain, but looking to throw my gear in the RV / truck and mess around from someplace like the top of Mt Wachusett or similar.

I was originally looking at the small FT-891 or the IC-7100 but then I started looking at specs:

FT-891 - Current Consumption: Rx: 2.0 A (Signal Present) Tx: 23 A
IC-7100 - Power Consumption Rx Max. Audio/Standby 1.5A/1.2A Tx Max. Power 22.0A

In Comparison

IC-7300 - Power Consumption Rx: 0.9A typical (Standby), 1.25A (Maximum audio) Tx: 21A (at 100W output power)
FT-991A Power Consumption RX 1.8 / 2.2 (Signal Present) TX 23A

For smaller QRP rigs: (For comparison)

Xiegu G90 - Power Consumption Receive current draw: 500mA Transmit current draw: 8A max.
FT-818 - RX 450 mA TX 2.7 A max
KX3 - RX: 150-190 mA TX (1 W): 750 mA TX (5 W): 1.2 A TX (10 W): 2.1 A TX (12 W): 2.4 A

The Elecraft KX3 with the external amp and panadapter is my dream rig - its also touching almost $4k and not happening... These number above make it seem like I should just buy a 7300 and be done with it for a good long time while I learn what the hell Im doing. The FT-891 doesnt save me much money as it still requires a separate ATU, and would require more gear if I want to setup a SDR for computer display.

Once I get this solved I then need to figure out the HF antenna nightmare
 
Working on studying for my General and looking at HF rigs for the fun of it. . .

The lower power QRP rigs may be different, but most 100 watt radios likes to see input VOLTAGE around 13.8v when transmitting, and probably won't rise to the rated power output when using a standalone battery topping out at about 12v. Don't let this trip you up though, as there's nothing to say you can't dial back the power and run happily at a reduced power output. There are step-up converters out there that connect to a 12v battery and outputs around 13v give or take but they present a load to the battery on their own and will shorten the charge life. The lithium batteries out there may be an option too, but I think they're still pretty pricey.

A viable option would be using a small generator 'round behind the RV and a 30 amp switching power supply feeding the radio.

Having owned or own a Yaesu FT-817 QRP rig and 100 watt Icom 706, 746, 7100, and 7300, I can say you pretty much can't go wrong with the 7300. It's such a great radio with nearly all the bells and whistles (antenna tuner, spectrum scope, USB for programming and digital modes) and is so fairly priced, it's probably a 'buy and hold' radio even if you decide to move to a more sophisticated radio down the road.

Good luck on the General man. To answer your question, I don’t think you’re missing anything.
 
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The lower power QRP rigs may be different, but most 100 watt radios likes to see input VOLTAGE around 13.8v when transmitting, and probably won't rise to the rated power output when using a standalone battery topping out at about 12v. Don't let this trip you up though, as there's nothing to say you can't dial back the power and run happily at a reduced power output. There are step-up converters out there that connect to a 12v battery and outputs around 13v give or take but they present a load to the battery on their own and will shorten the charge life. The lithium batteries out there may be an option too, but I think they're still pretty pricey.

A viable option would be using a small generator 'round behind the RV and a 30 amp switching power supply feeding the radio.

Having owned or own a Yaesu FT-815 QRP rig and 100 watt Icom 706, 746, 7100, and 7300, I can say you pretty much can't go wrong with the 7300. It's such a great radio with nearly all the bells and whistles (antenna tuner, spectrum scope, USB for programming and digital modes) and is so fairly priced, it's probably a 'buy and hold' radio even if you decide to move to a more sophisticated radio down the road.

Good luck on the General man. To answer your question, I don’t think you’re missing anything.
Thank you for the input.

Is a QRP rig like the 818 just a source of frustration for someone new to HF? The other direction I leaned was going with something ultra simple like a 818 and a simple wire antenna in a tree to start messing around before Im $1500-$2k deep into something I really am only just learning. Especially seeing the 818 is only running $550 at the moment... (Im interested in trying everything from phone,RTTY, and CW)
 
If you can toss a rope into a tree you can have a wire antenna setup in short order.
 
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