Avionics with FREE UK Delivery on orders over £200Open for website orders during lockdownOur Feefo Reviews

Dynon HS34 HSI Expansion Module


Please select an option...


The Dynon HS34 is an optional expansion module that extends the HSI function already built into and displayed on Dynon's EFISs. This panel-mounted device not only expands the HSI functionality but also enables several new features for any Dynon EFIS, EMS or FlightDEK instrument to which it is networked.The HS34 is available in vertical and horizontal panel mount configurations.

The expansion module concept provides exceptional value and performance while preserving the affordability of Dynon's existing equipment. This modular approach offers greater flexibility when configuring new aircraft panel systems and facilitates future expansion if so desired.

Expanded HSI Navigation Interface

While all of Dynon's EFIS instruments currently include HSI functionality, full compatibility with some GPS and NAV radios has been limited by the serial connection method.

The HS34 overcomes these restraints by adding ARINC-429, analog, and serial interfaces to cover many popular radios. With the addition of an HS34 to an EFIS, full compatibility is now possible with radios such as the Garmin 430/530. This includes advanced features IFR pilots demand, such as CDI auto-scaling and full vertical guidance information from WAAS-enabled units. The HS34 effectively eliminates the need to install a conventional CDI/GS head.

Superior User Interface

The front panel provides dedicated controls and indicators that optimize the pilot's control over the HSI. The controls are backlit to facilitate night flight conditions. Separate knobs are used for setting the Heading, the Course (OBS) or entering general purpose Values. Other controls include NAV and Bearing Source buttons that facilitate independent selection over each input. Pilots receive feedback of the currently selected navigation source type from separate GPS and NAV indicator lights.

Expanded EFIS/EMS Capabilities

In addition to expanded HSI functionality, the HS34 also provides several powerful features to interconnected Dynon instruments that include:

Use of the Value knob for adjusting the EFIS barometer, bugs, and timers. A built-in light level sensor to automatically adjust the LCD screen brightness Synthetic voice alert messages available for input to an intercom Additional EMS general purpose and contact inputs Network Link to Dynon's Instruments

The HS34 expansion module is network connected to Dynon's line of avionics via the Dynon Smart Avionics Bus (DSAB). This two-wire connection not only simplifies wiring but extends individual module benefits to multiple interconnected Dynon instruments.

The HS34 is supplied with a mounting bracket and two mating connectors with pins.


Dimensions: 1.639" x 4.903" x 4.951"
(4.16 x 12.45 x 12.58 cm)
Panel Cutout: 1.50" wide x 4.75" tall (3.81 x 12.07 cm)
Mounting: Rear-mounted bracket (supplied with instrument)
Weight: 12 oz (340 g)
Electrical: 10-30 Vdc, 3 watts
Connectors: 2 - DB25 connectors, mating connectors supplied
Operating Temperature: -30° C to 60° C
Storage Temperature: -30° C to 75° C
Humidity: 0-95% non-condensing

2 - Bidirectional RS-232 serial
2 - ARINC-429 receivers
1 - ARINC-429 transmitter
1 - Analog synchro resolver
1 - Marker beacon receiver input
1 - DME input
6 - EMS general purpose inputs
4 - EMS contact inputs
1 - Dynon Smart Avionics Bus (DSAB) interface
1 - Audio output to intercom

Compatible Devices

The HS34 is compatible with NAV radios using the industry-standard ARINC-429 or Analog outputs. It's also compatible with Navigation GPSs with either ARINC-429 or RS-232 serial output streaming either NMEA-0183 or Aviation format. The HS34 requires that you have at least an EFIS-D10A, EFIS-D100 or FlightDEK-D180 installed in your plane.
Feefo Reviews
The UK's Independent Review Site
Read All Reviews

Dynon HS34 HSI Expansion Module Reviews

Feefo Plus Rating
Feefo Plus Rating
Customer Comment

Quick and satisfactory communication

To calculate your shipping click here >>

UK Mainland & Europe:

FREE Shipping to UK on orders over £200.00
*excludes hazardous items

£5.50 inc VAT (up to 500g Royal Mail 1st Class recorded post)
£7.20 inc VAT/20Kg (ParcelForce 2 working days)
£12.00 inc VAT/20Kg (ParcelForce next working day).

International Sales:

Shipping costs can be calculated here >>.

*excludes hazardous items

All other delivery prices will be calculated and displayed at checkout

Some products entail special delivery costs (e.g. Hazardous goods)


We are an EASA part 145 approved organisation. Our policy is to sell only high quality products which offer good value for money. If you are not completely satisfied with your purchase please return the goods in original condition and packaging within 28 days of purchase for replacement, exchange, or a full no quibble refund.

World Class Service
Contact Us
If you have any questions regarding this product or any of our other services please email Customer Services or call us on 0131 447 7777 and we will be happy to assist.