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Yes, exactly! That's what the derating curve for the MFJ load shows as well. The 25kW rated load literally melted with only 10kW applied when its cooling fans shut down. Find a way to get rid of the heat and a resistor can dissipate immensely higher power.

It plugs into the OBD-II port of the car. Mount the meter face somewhere convenient and connect the cable. I'm very pleased with the gauge. It provides real time indication of fuel consumption and has taught me to increase driving efficiency considerably. I'm getting easily 25-30% better...

At work we have a 25kW dummy load that uses a 200 watt resistor. Before power is applied a water pump comes on, and the water run through two radiators with two fans blowing air through. The resistor shatters instantly if it isn't properly cooled. It's shown in the lower right of the first...

I have a ScanGauge in my car. It monitors fuel consumption, temperatures, engine load, battery voltage, and so on. http://www.scangauge.com/

The transmitter could also make use of a bandpass filter to reduce intermod at a busy site. High level signals arriving at the PA from nearby transmitters can be rebroadcast causing interference to other services. This is sometimes done at FM broadcast sites, even if the antenna services only...

I've bought two versions of heat strink tubing. The thin wall stuff works well for many applications. Another type referred to as thick wall has a sticky goo over the inside surface. As it is heated and shrinks the stuff seals things in very well. It's ideal for outdoor connectors. Look...

That's the room. The main transmitter was operating at 10kW into the load. There was a power outage and the dummy load didn't have back up power for the fan. The main transmitter was on generator power and continued to operate. I should take some pics of the 90 degree elbows in various...

Here's a 25kW air cooled load that overheated. There were aluminum drippings on the air exhaust. To the right is a 25kW liquid cooled load. It has a water pump and two radiators to get rid of the heat. The actual resistor is only rated at 200 watts, but with continuous water flow is good for...

The 8874 is used as a driver for the 3CX3000A7 in FM broadcast transmitters. Both tubes operate grounded grid. About 10 watts drive is capable of producing over 5kW output power 24/7. I don't have plate volt or current specs off the top of my head...

Excuses...

Has anyone managed to get their Larcan amps operational yet? Any pictures to share?

If it is for a single band antenna, install a shorted quarter wave transmission line with a Tee connector. The entire antenna is placed at DC ground, good for whatever power capacity the rest of the line is rated, and it's cheap.

You will find some interaction between the dipoles. When tuning, start at the lowest frequency band and work up.

Perfectly normal. Trace the wiring on the amplifier module. It will go to a coil towards the middle of the board, and then continue towards the front. From there you will see a through board connection to ground. http://members.rennlist.com/warren/larcan3.JPG I have other pics on my...

Visit some of your local radio stations and talk to the guys in the engineering department. Many old tube transmitters are being taken out of service and replaced with solid state gear. In the past year I've scrapped several 1kW FM transmitters and expect another couple 5kW transmitters to be...

If it is a hypothetical question, the transmitter should work with an antenna, mic and mixer. Get a CD player or computer to spin a few songs. However if you plan to ever do something legitimate it's the wrong way to start. Get approved type equipment and go through the proper channels and...

You may need to build a big bird's nest while installing the antennas... Another Larcan could be modified for 2 meters.

The inverted-V near the horizontal antenna could distort the pattern and cause SWR problems. You might also want to break the guy wires near the top into non resonant lengths with insulators. For omni work, I'd go with a vertical above the beam, something along the lines of a Shakespeare...

I built one with an oil furnace ignition transformer and two welding rods.

Pictures please. :)