445: SIMAV8 CNT1 COM/NAV Radio Review

In any construction of a realistic cockpit, high-performance avionic instruments can be said the next most important equipment next to the control stick, rudder pedals and gauges.  However, choices available on the market are limited, especially to those designed for general aviation simulation purposes.

The CNT1 COM/NAV Radio by SIMAV8 is a new avionic equipment that is designed and built with this intention in mind.


In contrast to the bulky Saitek Radio Panel I have been using since 2000, the CNT1 Radio has an appearance of a real replica of a true-to-scale Bendix King Radio unit commonly found on most general light aircraft.

It has a twin LED display for COM/NAV frequency readouts, two adjustable dual-layer rotary COM/NAV dials, two COM/NAV active and standby frequency toggle buttons, one DME display, and one NAV frequency IDENT button.

The active and standby frequency displays of COM/NAV are grouped next to each other horizontally.  This is based on the genuine layout used on the real Radio, rather than separating them on two rolls as the Saitek Radio Panel does.

Similarly, the two COM/NAV rotary dials are placed under the two COM/NAV displays directly, rather than sitting on the edge of the right hand side as found on the Saitek Panel.   This not only allows users to access the dials effectively but also prevents users from turning the wrong dial by accident.

Regarding the DME display, I have to say that the inclusion of it to the unit is a very nice touch to provide users handy references for the DME information without the need of extra hardware.

However, the blue-color LED is really not my taste, even though it does differentiate itself clearly from the red-color COM/NAV displays.  Surely this is purely personal; nothing to do with the function and design of the product.

Another nice and thoughtful design of the Radio is the IDENT button next to the DME display, which is rarely found on other similar products as far as I’ve seen.  It can send identity signals of NAV1 or NAV2 and then activates the corresponding NAV1 or NAV2 indicator on the audio panel.


The unit, available as a DIY kit, consists of three circuitries:

  • the front board where switches and encoders and OLED displays are mounted;
  • the rear board where LED driver chips and LEDs are mounted; and
  • the third one is the Arduino microcontroller unit that provides connectivity between the Radio and the flight simulator.

Hardware connection of the Radio to the computer is made thru the USB interface.  Software control is via a piece of dedicated program called SIMRadio from the developer.

No addition power supply is needed as the unit is able to draw enough power from the USB already, whether the USB port is directly on the PC or from a hub.

As the CNT1 was designed to be panel mounted at eye height, like in most real aircraft, the Radio does not come with a chassis.  The developer adds that this helps lowering the cost, too.

Regarding compatibility, the CNT1 Radio supports FSX, FSX-SE, P3Dv3 and v4 fully.   Other popular simulators, such as X-Plane 11, Aerofly FS 2 and Flight Sim World, unfortunately, are not (or not yet) supported.  (Edit: Frankly speaking, I don’t really care.)


Using the Radio is intuitive.   But I have to admit that due to the lack of start-up instruction, I ended up seeking assistance from the developer in order to activate the unit properly the first time I was using it.  After that, everything is simple and straightforward.

Basically, to turn on the unit, one just needs to:

  • Connect the unit to the computer
  • Execute the SIMRadio software
  • Load up a flight session in FSX or P3D

Then, the unit will turn on and display the current active and standby COM/NAV frequencies as well as DME data on the aircraft.

The only thing that requires attention when connecting the Radio to the computer the first time is the proper configuration of the COM Port in the SIMRadio software.

In order to activate the Radio properly, one must select the correct COM port from the drop down list for RU1 (Radio Unit 1) or RU2 (Radio Unit 2, if it is the second unit or selected as is the second unit) in the beginning.

Checking the “Auto” option helps configure the COM Port automatically, although I found it doesn’t work sometimes.

Moreover, one may need to toggle the Master Battery switch or the Avionic Master switch in order to activate the unit, or reactivate the displays if the connection is somehow dropped and reconnected.

These COM Port configuration steps were the only issues I couldn’t figure out by myself in the first place.

After that, adjusting the COM/NAV frequency is as easy as turning the dual-layer rotary dials clockwise or anti-clockwise.  The smaller front dial changes the decimal figures of the frequency, and the rear bigger dial adjusts the frequency before the decimal points.

Unlike the Saitek Radio Panel which is sometimes hard to adjust the frequency accurately and even skipping numbers when the encoder dials are swiveled quickly, responsiveness of the CNT1, and so reflected on the virtual cockpit, is quick and accurate.

Similarly, pushing the ACT/SBY buttons under the COM/NAV displays toggles the active and standby frequencies instantly and effortlessly.

The same performance applies to the DME display.

Should a dimmer COM/NAV display be required, one could push and turn the left rotary dial anti-clockwise to lower the brightness.   Or on the opposite, push and turn the left rotary dial clockwise for a brighter display.

However, the brightness will return to default after every power cycle, for which the developer says that an option will be added in the SIMRadio software update so that the adjusted brightness can be remembered.

Besides the COM/NAV frequency information, the SIMRadio software also contains many other useful references for the aircraft being used, such as XPDR codes, GPS position, etc.

In addition, there is even an option to allow the CNT1 Radio to connect to ForeFlight, a popular Electronic Flight Bag (EFB) applications on iPad for real pilots.


Being able to fly in an as realistic as possible cockpit is virtually the dream to almost all flight simmers, no matter the enrichment is to enhance the excitement in the flying game or to accumulate experiences for real life aviation practices.

SIMAV8’s CNT1 COM/NAV Radio is not a general product offering a bunch of universal features in a single box.   It aims to target the serious flight simmers who look for highly true-to-life cockpit experience.

If FSX Times had a scoring system, I would not hesitate to give the CNT1 Radio a 9 out of 10, based on the features, performance, built-quality and potential that the Radio could bring to any cockpit being built.

Anyone interested in the CNT1 COM/NAV Radio could click to visit the SIMAV8 website here.   There are some more related videos showing how the unit works.

In addition, you may like me finding the other projects from the developer, such as the COM/Annunciator and GPS panels, similarly interesting too.



  • A true replica of the Bendix King Radio
  • Additional DME display
  • Additional IDENT button
  • True-to-life form factor
  • Highly Accurate
  • Quick Responsiveness
  • Easy to use


  • Lack of documentation
  • Provided as a DIY Kit
  • Panel-mount design not for everyone


2 thoughts on “445: SIMAV8 CNT1 COM/NAV Radio Review

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