ACK A30.9 (Mod 9) Altitude Encoder FAA TSO

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Part# 11-02375
MFR Model# A-30.9


The ACK A30.9 (Mod 9) encoder is ideal for use with most GPS and TAWS systems, and works well with most of today's mode S transponders. Feature Gray code in 100ft. increments and RS-232 in 10 or 100 feet increments. Furnished with a 4 ft. harness, pre-wired jack, quick release mounting tray, fittings, static line, and installation manual. Reports altitude to 42,000 ft. Three Year Warranty.
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  • Avionics products manufactured by ACK Technologies, Inc. are warrantied against defects in materials and workmanship for a period of three years from their manufacture date. This warranty is limited exclusively to repair or replacement of the E-04 ELT and associated parts which were manufactured by ACK Technologies, Inc. the defective parts must be returned freight prepaid to our manufacturing facility. This warranty does not include repair or replacement of any part that has been improperly used, installed or physically damaged. This warranty does not cover any damage caused by chemical exposure. Discharge of the ELT lithium battery is not covered by this or any other warranty. Except as provided herein ACK Technologies, Inc. makes no express warranties, and any implemented warranty of merchantability of fitness for a particular purpose is limited in its duration to the duration of the written limited warranties set forth herein. ACK Technologies, Inc. shall not be liable for any direct, indirect, special or consequential damages arising from the use or misuse of this product. Except as provided herein no employee, agent, dealer, or other person is authorized to give any warranties of any nature on behalf of ACK Technologies, Inc. YOU MAY HAVE ADDITIONAL LEGAL RIGHTS WHICH VARY FROM STATE TO STATE
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Very simple replacement for my older / defective encoder. Calibration was spot on.

Paul H Verified Purchase

ACK A-30.9 ENCODER RS232 42K

May 23, 2022

This was orders for a new ADS-B installation paired to a new Stratus ESG and replacing a -3 version of the same model. The -9, with the RS232 connection, made all the other wiring unnecessary. Installation was a piece of cake.

Pacific A Verified Purchase

ACK A-30.9 ENCODER RS232 42K

April 12, 2022

This newer mod of a classic encoder features RS232 output used for adsb-in, etc. nice to have to rewire everything to simply add RS232 to an existing ACK encoder installation

Final A Verified Purchase

ACK A-30.9 ENCODER RS232 42K

February 1, 2022

Hooked-up as supposed to - Everything is working just fine

Mr R Verified Purchase

ACK A-30.9 ENCODER RS232 42K

January 12, 2022

Great product. Received package on a Sunday.

Dennis F Verified Purchase

ACK A-30.9 ENCODER RS232 42K

December 9, 2021


Dennis F Verified Purchase

ACK A-30.9 ENCODER RS232 42K

December 9, 2021

Works great must buy

Lorraine M Verified Purchase

ACK A-30.9 ENCODER RS232 42K

September 8, 2021

Arrived in good condition. Easy install.

Taildragger F Verified Purchase

ACK A-30.9 ENCODER RS232 42K

August 31, 2021

Don H Verified Purchase

ACK A-30.9 ENCODER RS232 42K

July 12, 2021

The encoder is working perfectly. Was able to just plug and play with a small setup on the transponder. At some point Ill have the RS232 wires added to get the 10 ft accuracy. Thanks

Mark M Verified Purchase

ACK A-30.9 ENCODER RS232 42K

June 9, 2021


Please note, Aircraft Spruce's personnel are not certified aircraft mechanics and can only provide general support and ideas, which should not be relied upon or implemented in lieu of consulting an A&P or other qualified technician. Aircraft Spruce assumes no responsibility or liability for any issue or problem which may arise from any repair, modification or other work done from this knowledge base. Any product eligibility information provided here is based on general application guides and we recommend always referring to your specific aircraft parts manual, the parts manufacturer or consulting with a qualified mechanic.

Q: What are the physical dimensions of the ACK A30.9 Encoder?

The ACK A30.9 encoder is 6" long, 2.65" wide, and 1.3" high.

Q: Will the ACK A30.9 (MOD 9) ENCODER pair up with the KT74 (mode S) transponder? Is the ACK A30.9 (MOD 9) ENCODER also a blind encoder? Is the ACK A30.9 (MOD 9) ENCODER also plug and play?

The ACK 30.9 encoder will work with any transponder. It is a blind encoder, that comes with a 4' harness. You will be required to crimp the corresponding pins on the other end of the harness to plug into your transponder. We do offer a custom harness for this connection, contact sales for a quote.

Q: What is the purpose of that large screw with the red cap in the center of the ACK A30.9 (MOD 9) ENCODER?

The connection in the center of the unit is for a static line connection.

Q: Can this put out gray code 100 ft resolution AND 10 ft resolution simultaneously? I have an Icarus altitude alerter that requires gray code, but also a WAAS GPS the requires 10 ft resolution via RS 232.

The mod A30.9 provides Gray code and two separate RS 232 outputs at 10 foot resolution. Up to 3 devices can be connected to each RS 232 output.

Q: Will this unit come with an Authorised Release Certificate or certificate of conformance?

No, a Manufacturer C of C must be requested at time of purchase. This option is given at the check out screen.

Q: Do you know if this ACK A30.9 encoder unit will work with the Stratus ESG Transponder?

Yes, the Stratus ESG is capable of both RS-232 and gray scale encoding.

Q: Will this ACK A30.9 encoder work with the Garmin GTX 327 transponder?

Yes. The GTX 327 will accept an RS232 input from this encoder.

Q: What is the stated current draw (average & maximum) on the Ack A30.9?

14VDC 160mA | 28VDC 220mA. Operation current 160mA typical.

Q: Can this ACK A30.9 encoder replace the AK-350?

PER ACK: The mod 9 can replace the AK-350, but they recommend the customer checking their pin out function to be safe.

Q: I have a ack-A-30 mod level 2 TSOC88l Will this model ack-A30.9(mod 9) work with no changes just disconnect old and connect the new.

Per the manufacturer, The model A-30 encoder Mod levels 0 through 9 utilize the same mounting tray and the same 15 pin Sub D connector and are directly interchangeable between mod levels.

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