We have included the answers to the most frequently asked questions (FAQs) regarding our Beacon Tester.

NOTE: When you click on a question, the answer appears in a gold box at the bottom.

A: The Creative Electronics ELT 1091C Tester is the product of several years of development, with the goal of developing an affordable, user-friendly, reliable and accurate tester. In order to accomplish this, it was decided to make a tester that was not dependent on any other off-the-shelf devices, but which was a completely self-contained device, using only quality components and dedicated firmware/software. The computer chip being used was designed specifically for embedded applications, such as this, and therefore lent itself well for this project. While a colorful display could be used, a more reasonably priced 4-line 80-character display was chosen, which adequately displays all of the data results from the tester. Finally, several innovative circuits has allowed us to obtain a very high degree of accuracy, requiring only one reasonably priced precision component.
A: Incorporating or adding a printer output interface would have added to the cost of the tester. We determined that relatively few users of the tester would use such a feature, while it would add to the cost and complexity of the tester. However, as time permits, we are planning to develop a printer interface option for the tester that will allow the transfer of the test data, using an industry standard format via WiFi to any computer set-up to receive that data. Our goal would be to sell this option for approximately $250.00. In the meantime, and even with the printer option, the tester will include a memory, which can store test results, which can then be reviewed and the data written into any convenient record.
A: The Creative Electronics ELT 1091C Beacon will test all beacons operating on the COSPAS SARSAT 406 MHz system. It was designed to test and check all of the requirements specified by COSPAS-SARSAT. This includes all Aviation, Marine, and Personal locating beacons. In addition, it also tests all beacons that operate on the 121.5 MHz emergency frequency.
A: Currently, we are working on a option to install a WiFi interface, allowing the collected data to be sent to any device capable of receiving the information in a standard format.
A: Currently. the only regulation that applies to this device is from the F.C.C. and involves the source of potential interference to or from other electronic devices. This device complies with paragraph 15.103c of the F.C.C regulations. As for the FAA, the device’s accuracy can be traced to the NIST and can be checked by anyone who has a signal source at 10.000 MHz that is traceable to the NIST and has the knowledge and expertise to do so. Currently, there is no requirement to do this. However, for peace of mind, one might want to do this periodically, perhaps every other year. Our tests have so far shown that there has been no significant drift of the included reference, even after several years.
A: The self-test function of a beacon is very limited in its scope and accuracy. First, the self-test function uses some of the same components to run the test as the components it is testing, such as its internal signal source. It has no way of knowing if it has drifted or changed and is out of tolerance. The self-test function is required to consist of a single transmission marked as being a test transmission, ignored by the satellite system. Therefore, the recycling requirement for the beacon is not tested with the self-test function. Also, the actual modulation of the signal cannot be checked except by a separate receiver capable of analyzing the transmitted signal. This tester does all of this and more and provides a pass/fail indication along with displaying the message content that was sent, something the self-test does not do.
A: The two modes of a beacon are the test mode and the normal mode. The test mode is specified to be a one-shot transmission, which is tagged as a test signal and is disregarded by the satellite system. The normal mode is tagged as a valid alarm signal. There is a required short delay from the time it is activated and the first actual transmission occurs. Then, the transmission is required to re-occur at a random interval of approximately 50-seconds. After the first transmission, subsequent transmissions are treated as a valid alarm and the search procedure is initiated.
A: We have found a good source for these is from Battery Junction at BatteryJunction.com

A: We ran into this situation while we were developing the tester. For our initial development, we designed a beacon simulator able to simulate a properly working beacon, as well as beacons with various faults or problems.  The simulator worked very well.

Eventually, we decided to purchase a new beacon, fresh-off-the-shelf, to use as a test check, along with a new certified and properly working beacon, as a backup to our testing.  We purchased an ACK model E 04 ELT, with a C/S Type # 0212 and serial number 02927, assuming and expecting it to comply with the COSPAS-SARSAT specifications (C/S T.001 issue 3 – revision 9), thereby verifying that the tester would correctly identify a properly working beacon, and thus provide a green light.  However, when we tested the ACK beacon, we got a red light and two error messages:  one for an unstable transmitter, one for excessive modulation, and one for a garbled message, which was a result of the unstable transmitter.

Initially, we assumed that the beacon was "okay," and the error was with our tester.  So, we re-examined our beacon tester to find out what was wrong with it, and after 6-weeks of intensive testing, without finding anything wrong with it, we decided to test the beacon directly using our lab equipment.  Much to our surprise, we found, that, in fact, the tester had correctly found and identified both faults with the beacon.

The two faults with the beacon were as follows: 1) The carrier was being amplitude modulated each time it was being phase modulated (There is no provision for amplitude modulation of a carrier in the specifications. As a result, the tester marked the carrier as being unstable, since it did not maintain a constant level); 2) The modulation exceeded 2.2 rad of phase modulation (the specification is 1.1 rad +- .1 rad).

Shortly afterward, I loaned a development tester to a friend, who was going to field test it for me.  The first beacon he tested was, you guessed it, a brand new ACK model E-04 ELT beacon.  Of course, he got the same result I did, so he sent it back to ACK, and they returned it, claiming that there was nothing wrong with it.  So, he sent the beacon to me.  When I tested it with the lab equipment, I found the same three failures to comply with the specifications.  It appears that there are several design flaws with this beacon, since several more have been tested with the beacon tester, all with the same results.  By the way, I own a Cessna 182 and was planning to install this beacon in my aircraft, after I was finished using it for testing.  Unfortunately, as a result of these errors, I am not going to install it in my aircraft, or for that matter, in any other aircraft I work on.  It may work, but I do not feel comfortable enough that I could rely on it.

A: Likely neither the method you used to test the beacon or the beacon tester itself is "wrong." For example, there are annual inspections, and there are "parker pen" annual inspections. The question, then, is how complete of a test or inspection did they perform, and how much variation did the person doing the inspection or test allow to pass the beacon, as being "okay?"

The Creative Electronics ELT 1091C beacon tester tests the following eight signal characteristics and decodes and displays the message, including the hex code and checks, for any discrepancies or inconsistencies in the message: 1) Frequency, including frequency drift; 2) Modulation, including checking for excessive or insufficient modulation; 3) Carrier amplitude stability, as well as other instabilities, such as spurious emissions; 4) Power output; 5) Antenna radiated signal strength; 6) Data clocking rates; 7) Un-modulated time; 8) Transmit time and recycle times. As a result, in order to get a green passing light, all measurements and tests must be correct. Even a single item out of specification will cause a red light, and then display the reason for the failure. The tester is impartial and does not care who manufactured is, or who or how the beacon has been tested previously. Only if the beacon is within the COSPAS-SARSAT specifications (document C/S t.001 issue 4- revision 2), will the test light turn green (passing). Otherwise, the light will be red.

So, it is our assumption that individuals passing beacons, that have failed on our tester, have not provided a complete test of the beacon, or they have disregarded some of the results. Some of the issues with beacons that have been passed by others included: excessive frequency drift, excessive modulation, insufficient modulation, carrier instability (including amplitude modulation, while being phase modulated), incorrect recycling times, and/or incorrect start-up times. This list includes beacons, which were sent back to their manufactures, and returned as "okay," as well as others that have been tested using other unknown methods, and have been passed as being "okay," even though they were not in compliance with the COSPAS-SARSAT specifications. We do not manufacture, or for that matter sell beacons, so we have no "ax to grind" with any beacon manufacturer. Our goal was to simply develop, what we believe to be, an excellent beacon tester at an affordable price. We are not interested in passing beacons that do not comply to the specifications, and may or may not work properly when called upon to do so. In other words, we sleep well at night knowing, that any beacon which passes our tester's tests, has operated as it was supposed to do at that time.

One of things we have found with our tester, is that even beacons that have come fresh from a manufacturer, which we assume and expect to be in compliance with the COSPAS SARSAT specification, failed. Furthermore, every one of that same failed model tested, displayed the same error messages, which suggests a design deficiency. Some of our customers have been kind enough to send, both the beacons in question, as well as their tester, so we can perform tests. So far, each tester passed our lab equipment tests, and we were able to determine that their beacon tester correctly identified all of the discrepancies.

There is no formal requirement to have our Beacon Tester re-calibrated, however, we recommend that it be re-calibrated biennially. Each new Beacon Tester sold includes a calibration certificate and a label on the enclosure with the current date of calibration, as well as when it would be next due. For more information, see our Calibration Service page.
The tester is receiving signals from a source, other than a beacon under test, probably on a frequency on or near the COSPAS SARSAT band. So far, one source has been identified as coming from a cell phone. Computers can also generate these signals. The solution would be to either turn the suspected device off or relocate it a distance from the tester.
The sensitivity of the tester was designed to respond to signals that were typical of those a satellite would receive at orbiting altitudes. Therefore, it requires a significant signal to make a realistic measurement of the signal radiating from the antenna, when close to the antenna. (FAR 91.207). In order to get meaningful test results, a consistent set of test conditions should be used. Therefore, we recommend that the tester be placed approximately 10 feet from the beacons antenna and in line of sight. A properly working beacon and antenna system will have a minimum signal inside the aircraft. As a result, the test taken from the inside of an aircraft will be unreliable.
beacon-test-recordYes, we have created a document to assist you. Please download our Beacon Test Record document. (PDF).
Not all testers are the same. The cost of a tester is not consistent with its ability to properly test a beacon for compliance with the COSPAS SARSAT requirements for beacons using their system their document c/s t.001. For example most testers do not measure the modulation, or frequency stability as well as other requirements of a beacon. As a result beacons which with our tester that are found to be not in compliance for these reasons will "pass" on testers that do not check these and other things.
The tester was designed to identify beacons that were not in compliance with the COSPAS SARSAT requirements for beacons using their system, their document c/s t.001. Beacons that work but do not comply with these requirements may not reliably function when required to under adverse conditions usually following an accident. COSPAS SARSAT had a reason for every requirement in their specifications. The Creative Electronics tester then provides you with the information you need to determine if the beacon is serviceable or not.