The high number of fishing vessels accidents in the Java Sea is due to the large number of fishing vessels that do not have safety support equipment in sailing, such as SART (Search and Rescue Transponder). So fatalities occur because it is difficult to find the location of fishers when an accident occurs. Also, the high cost of SART equipment on the market makes fishers unable to afford it. Research related to Mini SART-DMOM (Search and Rescue Transponder-DMOM) is an innovation tool with a working system almost the same as SART on the market, and this equipment has a lower price compared to SART sold on the market. In assembling the prototype, the main components used are GPS Neo 6m, Arduino Uno, LoRa and Wemos (ESP 8266). The prototype assembly is divided into Mini SART-DMOM and Mini SARR-DMOM (Search and Rescue Receiver-DMOM). In the prototype test that was carried out, it ran smoothly where the Mini SART-DMOM could get location via GPS. Lora sent the location data from the LoRa Transponder to the LoRa Receiver. The data received by the Receiver was sent by the wifi Board (Wemos ESP 8266) to be monitored live remotely via Web Blynk. However, in this trial, the maximum recorded range was required to be improved.