Author: N4GA – Rob
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Maximum Theoretical Power
You know how Ampleon releases LDMOS devices rated at extreme power levels, like their ART2K rated at 2500W? Unfortunately, that power rating really has nothing to do with linear use, which is what we need for amateur radio. That power rating is for a 100uS pulse at 108Mhz, with 75Vds, 50mA bias and 25C case…
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Whats the Goal here at N4GA.com
Anyone that’s corresponded with me about my amplifier designs knows that my goal is to design a broadband LDMOS amplifier capable of running acceptably clean without LPF filtering. However, there’s “acceptably clean” and then there’s the FCC 97.307 Emission standards that states this: (d) For transmitters installed after January 1, 2003, the mean power of any spurious…
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Transmit Receive Sequencing your Amplifier
Last year I got a lot of pings asking “where you been… why no posts… did you quit…” etc. I get it! It’s been since May 24, 2020 since I last posted. Well, I’m not a retired ham – still putting two kids (both engineers) through college! Also, work has gotten extremely busy this past…
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The MRF1K50N
I was searching Mouser for a new LDMOS recently, as my trusty ole 1k80h finally went “out of round” on me. In the last few years, I’ve soldered and unsoldered this device four times and used it in countless amp designs. I’ve certainly TRIED to let the smoke out of it but it lives on.…
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LDMOS Amplifier Testing Setup
Here’s the testing setup. The enclosure is “universal” and different pallets get dropped into it. In the pic you can see the exciter (Flex 6300), spectrum analyzer, power supply, dummy load, RF power meter, ammeter and oscilloscope. Hiding in the back is a inline RF sampler. The way I test and develop these amps is…