The QRPGuys Dummy Load/Power Meter is a 50 Ω, 12W rated terminated load that is useful tool when setting up or diagnosing most low power transmitters. Try plugging a dummy 1/4" plug (tip connected to sleeve) into the FX return and see if that cuts the sound to the speaker while still allowing you to use the FX send and master volume at line levels. This 10 ohm resistor will dissipate 5.8 amps at 58 volts. (50 ohms). A 25 Watt Dummy Load Dummy load described here can be used for up to 35 watts for short transmissions, and up to 25 watts for longer periods. So I had to give it a round shape, by shortening the fins of the heatsink. There is also a simple diode RF detector which rectifies and smooths the peak voltage, which can be read The dummy load kit comes with 20 1K 1% 1W resistors, a diode-capacitor rectifier for peak voltage readings using a DVM, and a BNC connector. Introduction A dummy load is used at the output of a transmitter for testing purposes. If we divide 1000 watts (dump load) by 30 volts we get a result of 33 amps. 50-Ohm 10-Watt Dummy Load (though with the instructions here you can build any wattage) Disclaimer: We are not responsible for what you do to your radio, any damages it may incur during any modifications you perform, any information from this site, or any projects you decide or attempt to build. A nice dummy load. I noticed 100 watt 50 ohm resistors on eBay listed at five for $6.50 or one for $1.99. Not needed but looks better. You can run 1KW CW or 2 KW PEP for 10 minutes. I tested it also with the dummy load resistor on the 5 volt rail and it ran much cooler with hardly any difference in the output voltages. This is 336 watts. But more importantly is making sure you are using an exact 50 ohm test variable that won't change like an antenna system might. I decided to install two 10 watt, 15 ohm resistors in parallel for a the dummy load. 1- PL259, I have a quick connector attached to my PL259 This is a simple DIY Speaker dummy load that was put together very quickly. (Refer to drawing and photo below) Editors Note: This simple project enables you to build a very small QRP 50 ohm dummy load that fits inside a suitable sized pill bottle and can take up to 10 watts of rf on hf. Pasternack 500 Watts Dummy Loads are part of over 30,000 RF, microwave and fiber optics products available for same day shipment. Parts needed: 8- 100 Ohm 2 watt carbon film resistors 1- Small piece of RG8 50 Ohm coax 1- Small piece of pref board. This is 240 watts. If your club has never tried a club build, this would be a good first project for several reasons. Dummy loads like this are used on base station setups, or test benches when you want to measure power output without actually broadcasting your signal. DIY dummy load resistor. I also assume these would as well take hours to build. 1- Med bottle, Or what ever you want to put it in. Build a wet dummy load using a 1 gallon paint can, at eham forum 100 W Dummy Load This was a project to make a dummy load or, as the finished thing is more correctly labelled, a fifty ohm resistive load. The Build: I have already seen a bunch of examples on how to build a dummy load with an abundance of same value 1/2 W resistors. Run continuous duty with 200 Watts CW or 400 Watts PEP. The one described here is capable of dissipating 100 Watts for short periods of time and provides a low power 50Ω port suitable for connecting a receiver or spectrum analyser for station monitoring. My dry dummy load consists of ten Globar 500 ohm resistors of either 100 or 200 watts each I forget. All that is needed to build your own dummy load … Discussion in 'Homebrew and Kit ... with fins about 1.5 in. After constructing an AMP6 T-Amp kit, and while testing the maximum power output using 4.7 ohm 50W ceramic power resistors the hot resistors had begun to scortch a cutting mat they were resting on and also melting the wire insulation of test leads which had fallen on one of the … A 100 watt resistor and SO-239. Instructions for building a 10 watt QRP dummy load using a Pill Bottle! Dry load can be operated in any position. 500 Watts Dummy Loads from Pasternack Enterprises ship same day. 10ohm resistor on 1.25v will pull 125mA and dissipate around 156mW Again, this isn't much of a test. This dummy load consists of 20 1K 1% 1W resistors connected in parallel to make a 50-ohm 20W QRP dummy load. DC - 3GHz. Those examples to my eyes looked like a complete mess. In the last installment of “The $50 Ham” I built a common tool used by amateur radio operators who are doing any kind of tuning or testing of transmitters: a dummy load. 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