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

  • Assembled ships tested, housed in clear Uno style case and 1.5m Cat cable

Vastly improves your rig experience

CatDisplay has a crisp 480x320 color 3.5” TFT screen. One cable is required and it plugs into a compatible Yaesu transceiver Cat port. It 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.

  • CTCSS, DCS, memory tags, extended memory functions and 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 on the CatDisplay. This is because the transceiver does not automatically send changes through the Cat port so CatDisplay must check. 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 also 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 transceivers only. 

3D Print an enclosure!

A very nice 3D printed enclosure, design by AK6DD Dave Duley, has been created. You can download Dave's from:


  • TFT displays are made of glass and are fragile. Treat it with respect and do not place it in direct sunlight, press or 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. If the display becomes corrupted during transmit, this is most likely due to high 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.

  • CatDisplay is a closed source product designed, made 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

Cat display is now in production and sold direct or through eBay
( search for "CatDisplay" << one word )
  • US$110.00 - Assembled & tested
  • This is a fully assembled and tested CatDisplay for FT-817/FT-818 or FT-857/FT-897 transceivers. It is mounted in a clear case and supplied with a 1.5m Cat cable. Just plug it in, set up Cat speed and it works. No assembly required. Shipping is US$11.00 by standard NZ air mail to anywhere. This is a 20 to 30 working day, NOT Tracked service. You will be emailed a link to user guide. 

Subpages (1): Purchase complete!
Chris Day,
Dec 8, 2018, 3:43 PM