Part of our The Yaesu FT-857D: The Complete Guide.
ALC Clipping and Power Foldback on 40 Meters
This is the complaint that comes up most in FT-857D circles: power output drops or the ALC meter spikes and clips specifically on 40 meters, even though other bands sound fine. It’s a well-documented calibration drift issue tied to the radio’s internal service menu, not a sign the finals are failing. The fix involves entering the radio’s service menu (power off, then power on while holding down the A, B, and C keys together) and resetting the affected menu items back to their correct calibration values. This is deeper than the normal user menu and it’s easy to make things worse if you’re guessing, so work from a documented reference for your specific firmware revision rather than trial and error, and note your original values before changing anything in case you need to back out.
Losing Memories or Settings After a Power Cycle
If the radio forgets memory channels or reverts settings after sitting unpowered for a while, the usual culprit is a weak internal backup battery that maintains memory when the radio’s main power is disconnected. These are getting old on every unit at this point given how long the 857D has been out of production, and a worn one won’t hold a charge long enough to preserve your settings between uses. It’s a known, inexpensive part to replace if you’re comfortable opening the case, or a quick job for a repair tech if you’re not.
Dead Pixels on the Display
The single-line LCD is a known wear point on used units, and dead or discolored pixels are the most commonly reported cosmetic issue. It doesn’t affect RF performance, but it does make the radio harder to read at a glance, which matters more than it sounds like on a radio that already buries information in a small display. The screen is a separate, replaceable part, and a replacement runs around $60, a fair repair cost if you land a radio that’s otherwise clean. Worth checking closely under bright light before you buy used, since a dying pixel or two can be easy to miss in dim listing photos.
No Native Antenna Tuner
This one isn’t really a fault, just a design reality worth flagging: the FT-857D doesn’t have a built-in antenna tuner, unlike some of the radios I compare it against elsewhere. If your antenna isn’t already close to resonant, you’re pairing it with an external tuner, and the radio’s protection circuitry will fold back power hard on a bad SWR match rather than let you push through it. That’s the radio doing its job, not malfunctioning.
Fan Noise or a Fan That’s Stopped
The internal cooling fan on the 857D is a small, continuously-run component, and after years of duty cycle it can get noisy or seize entirely. A noisy fan is usually just accumulated dust and lubricant breakdown and can often be cleared with compressed air and a drop of appropriate lubricant on the bearing. A fan that’s stopped completely needs replacing before you run the radio hard, since the finals rely on it during extended transmit, especially on HF at full power.
If you’re troubleshooting a used unit you just picked up, my guide to buying a used FT-857D covers what to check before you hand over money in the first place.