CatDisplay is an easy to connect external display for the Yaesu FT-817/ND, FT-818ND, FT-857/D, FT-897/D, FT-100/D transceivers.

  • Ideal for the visually impaired.

  • Compact, easy to connect, easy to use.

  • Makes a complicated transceiver easier to use.

  • Helps with failing displays (missing lines).

  • Instantly see most settings!

  • Less use of menus, less chance of forgetting.

  • Now also supports Analog S-Meter output!
  • Supplied assembled, tested in ccustom 3D printed case & includes 1.5m Cat cable

Vastly improves your rig experience

CatDisplay has a crisp 480x320 color 3.5” TFT screen. It is super easy to install - plug the supplied Cat cable into the display and a compatible Yaesu transceiver Cat port. CatDisplay reads the transceiver's EEPROM data, detects & decodes any changes then updates the display. The custom algorithm also detects transceiver use and slows down data requests when idle. 

CatDisplay reads information from the transceiver only. It does not write information to the transceiver and cannot be used to control the transceiver. If your looking to control the transceiver, CatDisplay cannot do this.

Unlike other devices like computers, tablets, smartphones and similar, CatDisplay only reads data from the transceiver. It can not cause EEPROM wear and will therefore not cause damage to the transceiver.


  • CatDisplay does not have a CAT pass through port so you cannot plug another CAT device into the CatDisplay. It should work with other Cat devices that have a pass through port.

  • CatDsiplay was designed to work with the transceiver rear CAT port. On the FT857 & FT897 series that also support a microphone CAT port , a separate power source will be required to make it work. CatDisplay draws about 130mA & has a standard 2.1mm DC jack for this purpose.

  • CTCSS, DCS, memory tags, extended memory functions & other less frequently used features are not displayed. Transceiver must be in VFO mode for all indicators to correctly display.

  • Some changes on the transceiver do not show up immediately. This is due to the way Yaesu programmed the transceiver. Only the most important changes are checked regularly to ensure the display remains responsive.

  • CatDisplay does not show actual SWR but does have a high SWR alert. It does shows output power & modulation as reported by the transceiver.

  • CatDisplay works with Yaesu FT-817, FT817ND, FT-818ND, FT-857, FT-857D, FT-897, FT-897D and now, FT-100 or FT-100D transceivers only. 

  • RS232 version compatible with all new Yaesu transceivers due Q2, 2021.


  • TFT displays are made of glass and are fragile. Treat it with respect and do not place it in direct sunlight, press or try bend it.

  • The cable between CatDisplay and transceiver has fragile pins in its plugs. The plugs only go into the sockets one way. Do not force them or you will break the plug, socket or both.

  • High RF fields may cause interference. Even though CatDisplay has integrated RF suppression, if you find the display becomes corrupted during transmit, it is most likely due to an excessive RF field which needs to be remedied. The most common cause is poor earth connection, high antenna SWR or very close proximity to the antenna and or feed line.

  • CatDisplay is a trade mark & closed source product designed, hand assembled, tested, programmed and sold only by ZL1CVD Chris Day, Oamaru, New Zealand. As per the terms of the Arduino LGPL license, compiled object files will be provided, upon request, to customers who purchase CatDisplay. If for any reason you do not agree with this, then please do not purchase CatDisplay.

How to Order & Pricing

Sale is for assembled, tested CatDisplay in custom 3D printed case with 1.5m Cat cable. There are models for all versions of FT-817, FT-818, FT-857, FT-897, FT-100 & FT-100D transceivers. No assembly required.

Standard shipping is US$14.50 by NZ air mail to most countries. This is a NOT Tracked service.

Due to reduced flights & Covid lock downs, delivery times cannot be guaranteed.

Cat display is also sold on eBay. Simply search for "Original CatDisplay" 

Subpages (1): Purchase complete!
Chris Day,
Dec 30, 2020, 2:35 AM
Chris Day,
Dec 30, 2020, 2:48 AM