• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

Shameless plug for SWR meter cal plugs.

nomadradio

Analog Retentive
Apr 3, 2005
7,422
12,208
698
Louisville, KY
www.nomadradio.com
Yes, I sell stuff on fleabay. Mostly I restrict hawking it here unless it serves to answer someone's question, or to announce a new toy.

This falls in the latter category. A shameless plug, if you will.

Maybe that's what I should call this set of four RF load resistors, the Shameless Plugs.

Maybe.

What they will do is tattle on a SWR meter that's not calibrated strictly to a 50-ohm match reading one-to-one.

Nearly every simple SWR/wattmeter will have no way to calibrate the SWR scale. There will be trimpots for wattage and modulation scales, but that's it. The SWR accuracy is usually dictated by the mechanical tolerances of its construction.

I haven't posted these yet, but I'll offer a set of four "shameless" plugs. Each a proper PL-259 with a 5-Watt metal-oxide resistor inside. No, they are not proper "non-inductive" resistors. They are low-inductive resistors. Plenty good enough for 27 MHz or below. Probably not outstanding past 50 MHz. Haven't made any measurements up there. Probably should.


9bYXFB.jpg



The resistor inside each one is rated for 5 Watts. It should withstand a 4-Watt carrier for as long as it takes to flip a switch, set the "Cal" knob, flip a switch back to the "SWR" side and observe the reading.

Just not an all-day dummy load.

The four steps are 24 ohms, for a two-to-one reading. 50 ohms, 100 for a two-to-one above 50 ohms, and 150 ohms for three-to-one.


0jhfoI.jpg



Should also serve to calibrate the SWR warning light on a radio that has that feature.


kvh9ZM.jpg



Bear in mind that these are five-percent resistors. Should be close enough for the average SWR meter.

Haven't made enough of them to list for sale yet. Still working on the price. Kinda depends on how much labor it takes to build four of them.

But it's a sneak peek, anyway.

73
 
Last edited:

dxChat
Help Users
  • No one is chatting at the moment.