Becoming Acquainted With The ACK E-04 ELT – The Hard Way

Up until today the ACK Industries E-04 ELT (emergency locater transmitter) has remained in its box so thought now would be as good as any to think about installing it in the cockpit. The long box containing the E-04 ELT and its supporting hardware was located and opened in order to become better acquainted with the goodies inside. After reviewing the instillation instructions (both ACK and Van’s) and fondling the hardware a bit, it quickly became apparent much to my surprise “BATTERIES NOT INCLUDED”. Well that is not entirely true, the E-04 ELT comes with a large specialized battery pack already attached … but there are two support items (the remote control panel indicator and the audio alert indicator) that much to my dismay, require batteries. Of course, they could be an easy to find standard C, AA, AAA, transistor radio battery, etc. …but nope, you have to hunt for these babies. The remote control panel indicator uses a Duracell PX28L 6 volt Lithium battery, or equivalent. The audio alert panel uses a Duracell CR-2, 3 volt or equivalent battery.


Before continuing with the instillation, I wanted to test everything first … so the search was on for the batteries. My first choice would have been Radio Shack but the local store has closed, so began wasting time driving around to various stores without much luck. Then a thought occurred, I may have seen these types of batteries used in photography equipment … so headed to a camera shop and sure enough, they had both batteries, just not in the Duracell brand.

The orange ACK-E04 ELT in the background comes with a battery attached to the unit by four screws … but the dreaded phrase “BATTERIES NOT INCLUDED” applies to the audio alert indicator and remote control panel in the foreground.


With the necessary batteries in hand, the screws were removed from the remote control panel  indicator and audio alert panel allowing the plastic cases to be split open to gain access for installing the batteries.

The remote control panel indicator with battery installed is on the left and the audio alert panel with battery installed is on the right. The dark blue band on the right edge of both batteries denotes the positive end of the batteries.


The finishing kit came with a long modular phone cord. Its purpose is to interface the remote control panel indicator on the instrument panel to the audio alert panel mounted alongside the ACK E-04 ELT. Van’s instructions would have the builder use a modular phone cord coupler on the end of the long phone cord to interface with a short phone cord that then plugs into the audio alert panel. This setup is a little kludgy for my liking and there is no real reason that the modular cord can’t be connected directly to the audio alert panel …. other than it won’t work. Plugging the cables together in such a fashion will cause the red LED light in the remote control indicator to flash continuously … which indicates the wiring is not correct. This is because the wiring for the modular cable needs to be straight between the two devices. One solution is to flip the modular connector plug on the phone cord. Because access is easier at the instrument panel end of the phone cord, the modular connector was cut off and the replacement modular connector was flipped 180 degrees then crimped onto the wires. My modular crimping tool was at the southern outpost, so Mike and Glen loaned me the one they use at their job sites.

Using the modular plug crimping tool Mike and Glen loaned me to install a new modular connector onto the end of the phone cord. The new modular connector was flipped 180 degrees on the cord and crimped. This will convert the phone cord to a straight cable allowing the phone cord to be plugged directly to the audio alert panel without needing the kludgy modular cord coupler and patch cord.


After installing the new modular connector on the phone cord, an ohm meter was used to buzz out the cord to make sure all four wires have continuity … all was well. Now with the phone cord plugged directly into the audio alert panel at one end and the remote control indicator at the other, the red LED light on the remote control indicator was not flashing … a good sign! Wanting to do a quick check of the ELT, everything was wired together and the antenna attached … waited until the top of the hour to arm the ELT and ran the self-test by pressing the reset button on the remote control indicator. All indications were as described in the ELT instillation manual. Unfortunately, I did not have a handheld radio with me so could not tell if the ELT actually transmitted a one second burst … so will need to take the handheld to the airport to verify that the unit is actually transmitting.

Performing a self-test on the ACK E-04 ELT. The unit was armed with my left hand and the reset button on the remote control panel indicator in my right hand was pressed to initiate the test. Received one flash on the LED and heard sound from the audio alert panel. All indications were per the instructions.


At this point in time, I don’t foresee any issues with eliminating the modular coupler and modular patch cord as has been done by reversing the modular plug on the phone cord and connecting the phone cable directly to the audio alert panel. If there is, I’ll return from the future and edit this post accordingly … but for the time being it appears to be smooth sailing in ELT land after learning the hard way “batteries not included”.