FT 817 vs FT 857 QRP . What are the differences? Which one to use for portable operations / QRP ? Contest DX? More power or less power?
The YAESU FT-817 is a true QRP rig with 5 Watts max.
The Yaesu FT 857D has up to 100 watts.
The real advantage of the FT-817 is it’s very low current draw when it’s not transmitting. The FT-817ND draws 0.25 amp squelched and 0.45 amp when receiving. Compare that to the FT-857D, which draws 0.5 amp squelched and 1 amp when receiving. That means that the QRP rig will last twice as long on the same battery. That’s a pretty significant increase when depending on a battery for operation.
Yaesu Ft 817 vs Yaesu FT 857 in portable operation – What about the digital processing?
The FT 817 ND does not have DSP. Many times happens with my FT 817 ND that I could not get through the noise to make a contact. The FT 857 has a DSP. Click down here on the arrow to watch video that compare FT 817 and FT 857.
Transmission: The yaesu FT 857 has obviously more RF power than the 817. But you can easily hold the transmit down to 5 watts (yes, the power is fully variable) and use headphones and it is a good QRP rig with many more features than the 817, but of course it is heavier, not unreasonably so since you can push it to 100 watts if needed to make a contact.
The two rigs are both winners. Both rigs will work well from a sealed lead-acid battery (SLAB) and a 7 ampere-hour slab will give you about 90 minutes operation at full power SSB. This is plenty for a typical Summits On The Air (SOTA) operation. A 12 Ah SLAB will give you about 2.5 hours but it weighs twice as much. Click down here on the arrow to watch video that compare FT 817 and FT 857.