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Hmm. 1.34 horsepower per kilowatt. A conservative 200 kW input to the final would get you 100,000 out, more or less. Minimum generator power 268 horsepower. Plus however much more to cover efficiency losses. A local guy had an air-cooled VW motor mounted in a frame at the rear of his shootout...

Not really. Last guy anywhere near that area I know who's qualified moved to the US Virgin Islands a while back, 73

Don't bother. 73

The APU alone would be loud enough to alienate my neighbors. 73

Simply replacing the stock final and repeaking the output coil is all there is to it. You won't see anywhere near double the power. More like one-third to one-half again higher reading. but folks who worship small boosts in the wattmeter reading will love it. Just be sure to apply fresh...

Haven't tended to a "walk-in" transmitter in 50-plus years. It was a 1948 Gates AM broadcast transmitter. Had glass windows so you could see the color of the driver and final anodes. The driver-stage plate meter had been splattered and management wouldn't spring the bucks to replace it. We tuned...

Hmm. Tough to shame someone who has no shame to begin with. 73

They give you operating specs for class C RF. 120 Watts drive for 220 KW output. Grid driven, of course. The neutralizing capacitor's plates would look like the covers from an oil drum. No guidance on drive power needed for linear operation. 3-inch heliax might be too small. Unless it's located...

One word. Enshittification. 73

Bias setting is all about device current draw with no drive. Manufacturing tolerances cause the exact gate voltage needed to differ from one part to the next. That's why there is a trimmer pot, to compensate for the gate-voltage difference from one MOSFET to the next. Yeah, measuring gate...

Trust me, the type number really is LM3086. It was National Semiconductor's licensed copy of the RCA CA3086. The type number prefix "LM" on a Nat Semi linear chip was supposed to mean "Linear Module". Or so I was told. 73

Sure looks like a tweety bird to me. https://www.worldwidedx.com/threads/and-now-for-something-completely-stupid-the-tweety-bird-noise-toy.270184/ 73

I'll guess that a close look at the band switch with a bright light will reveal burned spots on the contact points for 40/80 meters. Probably never cleaned the oxide from the silver plated contacts. Once the arc begins, metal gets destroyed. Sounds as if the previous owner liked 40 and 80...

I would recommend 40 mA just to be safe. 73

Not to pick nits here, but didn't the suffix letter "D" indicate a desktop model? Those are safer to ship than the floor console models, especially since they don't have a heavy filter choke in the HV supply. Still a big beast to package and ship., 73

Better you than me. 73

Probably can't just pull out melted plates until it frees up. Is there a safety choke in parallel with the Load control? Leaving it off can cause arcs on the Load control's plates. Depends on the antenna you use. A series-fed antenna that tests open-circuit allows DC voltage to build up on the...

Clicked on his avatar, says last seen Dec 7, 2025. 73

Owner's manual says 1S2076. A generic 1N4148 is a near-identical substitute. 73

Could it be confusion between the four-see-ecks four hundred tube and your tube? The "four" is a tetrode. The drive requirements are scandalously small. The "three" is a so-called power-grid tube. The data sheet says the grid's power rating it 5 Watts. That's average power. That tube has a power...