PSU for LawMate 500mW Transmitters Assembly and Operation Manual Introduction Thank you for purchasing LawMate 500mW Power Supply. This power supply was specifically designed for the 500mW LawMate transmitter modules. It can be used with 1.2GHz or 2.4Ghz versions. This kit requires medium soldering skills because of the small SMD surfaces you need to solder the wires to. Before starting to assemble the PSU, please examine your kit that is has all the necessary parts and nothing is missing. The above picture shows all the items which should be in your package. Also please see the list of the items on the next page to make sure everything is in the bag: Page 1 of 6
Content: 1 x Connector cable 1 x Plastic plate 1 x Power supply 1 x Heat shrink If any of the above is missing please contact us at customerservice@nghobbies.com for replacement parts. Description: The PSU for LawMate 500mW transmitters was specifically designed and created such to be an easy mount on the back of the LawMate transmitters allowing access to the dip switches through the cut-out part on the PCB. Using or implementing this power supply for your setup will benefit you with the following: Up to 1A very clean power Power supplied to the camera can be 5V or 12V (requires 3 cell LiPo battery) Easy servo type connections, 3 pin for power and 4 pin for video/audio in Reverse polarity protection at the battery level Very bright red LED indicating operation Small size, barely any weight and stylish look Easy fit in most pan and tilt pods available on the market today Items required and not supplied: 1 x Soldering iron with thin solder wire, solder paste or better liquid rosin solder flux 1 x One strip of double sided tape 1 x medium CA Tools required: The following tools will be required for assembly: Fine tip soldering iron, not more than 60-75W Hobby knife Solder paste Gas or Zippo lighter Experience required: Small surface mount soldering skills Page 2 of 6
Step 1: The connection cable from the PSU to the LawMate transmitter is provided in the package, however we will need to prepare this cable and to solder it to the circuit board. The cable has a smaller and a larger connector. Please verify that the smaller connector fits your LawMate transmitter perfectly before cutting the cable. We recommend cutting the cable to about 1/3 rd of the length (1.5 inches or about 4 centimetres from the end of the white connector). Step 2: Since the cable cut is very close to the connectors, and the plastic isolation around the cable is very stiff, we do not recommend using hobby knife or other cable stripping tools to strip the end of the cables for soldering. Instead we recommend using the flame of a lighter. Inserting the thin cables one by one in the flame the plastic isolation will shrink a few millimetres back exposing the wire mesh underneath. This is usually enough to expose enough cable for soldering it to the circuit board. If the exposed cable is too long, that can cause short circuit, so you should cut the exposed length to maximum 2 millimetres: Page 3 of 6
Step 3: The LawMate PSU has a 4 pin connector to connect the camera to the transmitter. This is designed in such a way that it will accept a standard servo connector wire if no audio is needed or if audio input is required a standard 2 pin connector will have to be used. The pin out of the connector starting from the middle of the board is the following: Battery Connector: Pin1 = Ground Pin2 = Battery in Pin3 = Ground Video Connector: Pin1 = Ground Pin2 = Camera Voltage Pin3 = Video from the camera Pin4 = Audio in As you can see, if you do not need the Audio, you can use a standard 3 pin servo connector on the camera end to supply power to the camera and to feed the video signal back to the transmitter. The camera voltage can be set to 5Volts or the voltage of the battery connected to the battery connector. In order to power a 12Volt camera you will need to connect a battery NOT more than 3 cell LiPo to the battery connector. Before soldering on the connector cables we recommend setting the battery voltage. This is done with a little solder-bridge over the corresponding pads: The middle pin provides the voltage going out. The pin on the left is the 5V coming from the regulator and the pin on the right is the 12V coming from the battery. You will need to create a solder bridge between the middle pin and the one on the left (as on the above picture) to provide 5V for the camera or the middle and the pad on the right to provide 12V for the camera. Page 4 of 6
Step 4: After the camera voltage has been set to the one desired, you can solder on the pigtail to the circuit board. To make your life easier we recommend to follow these steps carefully: Dip the exposed end of the cables into the liquid rosin flux. Heat up your soldering iron and melt a little blog of solder wire. Slide the exposed wire end through the liquid solder blog on the tip of your soldering iron. This will ensure proper tinning of the exposed wire lead. After you finished all 4 wire ends, use clipping pliers to shorten the wire ends to be th same length for all 4 wires as well as when soldered on not to extend beyond the soldering pad. Now starting with the red wire solder on each wire to the circuit careful not to heat up the pads too much, so you do not melt the isolation on the cables any further than it is required. At the end you should have something similar to the picture below. Step 5: Use a drop of CA to glue the transparent plastic part from the package to the left side of the circuit board. This will make the left side approximately as high as the coil on the right side making the installation on a flat surface much more convenient. The plastic cover has a little cut-out to extend over the LED this way dispersing the light coming from the LED in all directions making it easier to be seen. Use the above picture as a reference on how to glue the plastic cover to the circuit board. Be careful, as after the CA cures, you cannot remove this piece from the circuit any more. Step 6: Use a piece of double sided tape on the bottom of the circuit board, to fix the PSU to the top of the LawMate transmitter: Page 5 of 6
Step 7: Before this step you would have to set the transmitter to the channel you want to transmit on. You can have access to the switches later as well, but you will need to cut out a piece of heat shrink to have access to it. Most people do not change channels very often, those can preset the channel before heat shrinking and leave it like that after. When you are satisfied with the position of the PSU over the transmitter, you can plug in the cable. Carefully bend the cable to the back and carefully pull the heat shrink over the whole assembly. Step 8: Use a heat gun to shrink the plastic over the whole assembly. Be careful to leave a little edge flowing over the front and the back but not too much so you do not cover the pins where you need to connect the camera and the battery later. When satisfied with the results and the plastic cooled down you can use small scissor or a hobby knife to cut a window in the heat shrink to allow air flow over the heat sink on the transmitter: Copyright @ 2011,, New Generation Hobbies. Page 6 of 6