Introduction: When Your Radio Forgets Everything
If you’ve owned the Yaesu FT-857 for any length of time, you might have encountered a frustrating issue: after saving repeater frequencies, memories, or custom settings, the rig forgets them all the next time you power it up.
Whether you’re a mobile operator, a field enthusiast, or a base station user, this kind of memory loss can be more than just annoying — it interrupts operations, erases critical data, and costs time.
This in-depth guide explores why the Yaesu FT-857 (and FT-857D in some cases) experiences memory retention issues and outlines permanent solutions to stop the forgetfulness once and for all.
Understanding the Yaesu FT-857 Memory System
The Yaesu FT-857 was built as a rugged, compact, all-mode, all-band transceiver for amateur radio operators. It stores a wide range of user settings, including:
- VFO A/B frequencies
- Repeater splits
- Memory channel names
- Menu settings
- CW keying speed and tone
These settings are held either by a battery-backed volatile memory (in early models) or non-volatile EEPROM (in later revisions like the FT-857D).
When memory is lost:
- You must re-enter repeater frequencies
- Custom configurations disappear
- The radio boots to factory defaults
Common Causes of Memory Loss in the FT-857
1. Dead or Weak Internal Backup Battery (Applies mostly to FT-857)
Early production FT-857 units use a coin cell lithium battery (such as CR2032 or CR2450) mounted on the control board to retain memory settings. If this battery dies:
- The radio resets after being powered off
- All stored data and configurations are erased
- The internal clock and last used VFO state are lost
Solution: Replace the Backup Battery
- Open the rig carefully by removing the top and bottom covers
- Locate the control board, typically under the top cover near the display
- Identify the coin cell battery (soldered or socketed)
- If soldered, carefully de-solder and replace with a new one
- If socketed, simply pop in a fresh battery
️ Important: Use ESD-safe tools and always disconnect external power before opening the radio.
2. EEPROM Corruption (Often in FT-857D Models)
Unlike earlier models, the FT-857D stores memory in a non-volatile EEPROM chip, which does not require a backup battery. However, memory corruption can still occur due to:
- Static discharge
- Voltage spikes
- Sudden shutdowns
- Overheating during extended use
Symptoms include:
- Radio powers on with default settings
- Previously stored memories are gone
- Menu settings revert after every shutdown
Solution: Perform a Full Factory Reset
A full reset will clear any corrupted memory blocks and restore the EEPROM’s baseline configuration.
Steps:
- Power off the radio
- Hold down the FUNC + V/M keys
- While holding, power on the radio
- Follow the on-screen prompts to complete the reset
Tip: Back up your settings with CHIRP or Yaesu’s ADMS-4B software before performing a reset.
3. Improper Power Shutdown Procedure
The FT-857 is designed to save settings only after a proper shutdown using the front panel power button. If you frequently:
- Disconnect the power cable abruptly
- Turn off your power supply instead of using the rig’s power button
…you risk memory write failures.
Solution: Always Use the Power Button
- Shut down the radio using the PWR button on the front panel
- Wait 2–3 seconds after shutdown before unplugging or powering off your supply
- This allows the EEPROM time to complete the save process
4. Power Supply Instability or Low Voltage
Low or unstable voltage, especially during power-up or shutdown, can affect how settings are saved to memory. If your power supply:
- Dips below 12V
- Has poor regulation
- Spikes during switching
…it can cause intermittent memory problems.
Solution: Use a Clean, Regulated Power Supply
- Choose a 13.8V DC power supply rated for at least 20A
- Add a ferrite choke on the power line to prevent RF interference
- Use fused leads and secure connections
Best Practices to Prevent Memory Loss
Here are some habits and hacks to ensure your FT-857 retains its memory for the long term:
| Action | Benefit |
|---|---|
| Replace the backup battery every 3–5 years | Ensures stable memory retention |
| Use CHIRP or Yaesu ADMS-4B software for backups | Easy restoration of lost memory |
| Shut down with power button, not DC switch | Avoids write failures |
| Avoid cheap or noisy power supplies | Reduces risk of EEPROM corruption |
| Ground the rig properly | Protects against static discharge |
| Store settings on computer | Acts as a restore point after factory reset |
Advanced Tip: Save and Restore with CHIRP
CHIRP is a free, open-source programming software for amateur radios. It supports the FT-857 and can:
- Read current memory settings
- Save memory channel files to your computer
- Restore data in case of loss
Download CHIRP: https://chirp.danplanet.com
Regular backups make EEPROM resets less painful.
What If None of These Fixes Work?
If your FT-857 continues to lose memory even after:
- Replacing the battery
- Resetting the EEPROM
- Verifying your shutdown method
…it could indicate a deeper hardware fault, such as:
- Failing EEPROM chip
- Bad solder joints on the control board
- Faulty power control circuitry
At this point, the best course of action is to:
- Contact a Yaesu-authorized service center
- Consult a qualified ham radio technician
- Post on trusted forums like QRZ or eHam for guidance
Tools and Parts You’ll Need
If you’re planning to tackle this issue yourself, prepare with the following:
| Item | Use |
|---|---|
| CR2032/CR2450 Coin Cell Battery | Backup battery for older FT-857s |
| Soldering Iron with Fine Tip | For battery or EEPROM rework |
| ESD Wrist Strap | Prevents static discharge |
| Precision Screwdrivers | For safe disassembly |
| Multimeter | To check voltage stability |
| Heat-resistant tweezers | For handling small parts |
| CHIRP Software | For backup and restore |
Community Help Resources
You’re not alone. Many FT-857 owners have shared their experiences and solutions across the web. Join these communities for support:
- QRZ Forums – https://forums.qrz.com
- eHam.net Reviews & Forums – https://www.eham.net
- Groups.io FT-857 Group – https://groups.io/g/FT857
There you can:
- Share your symptoms
- Ask for component-level repair advice
- Download user-submitted schematics and fix guides
Final Thoughts: Fix It and Forget It
The Yaesu FT-857 is a workhorse rig, built for flexibility and performance. But memory retention issues can cripple its usability — especially if you’re using it on the move or in remote areas.
By understanding the root causes — whether it’s a dead battery, EEPROM glitch, or user error — you can apply lasting solutions that restore your radio’s reliability.
Don’t let a forgetful rig slow you down. Replace the battery, use the power button, and back up like a pro. That way, your FT-857 will serve you faithfully for years to come.
