Building a saltwater dummy load

[295 antenna]

Cool looks like you got it working !

[Bluerunner]

I have a relative who is a chemistry teacher. For years he had his students used salt water to demonstrate electrolysis. A whole classroom of kids doing the project didn't produce enough chlorine to even be detectable by scent. He stopped using salt to avoid hyper-protective parental complaints and potential BS litigation. There is more chlorine given off by filling a glass with tap water than the experiment produced.

To avoid abandoning the experiment or crowding everyone around a fume hood he switched to using baking soda as the electrolyte. Worked just as well, less corrosive on the electrodes & wiring too.

No uninformed soccer moms wringing their hands over the perception of "toxic" gas. After all the **Censored** used chlorine gas to murder thousands of people in the war, and they have the students making it in class! I can see where the lawyers could have a field day beating that drum. After all this is Louisiana with more starving lawyers per capita than any other state in the union. (Lions & Tigers & Chlorine.. Oh My!)

I wonder if baking soda might do as well or better? Might try it when I get around to making a salt water dummy load.

I have wanted to try the Wilkinson Divider / Combiner to have one radio drive two parallel amps and then combine the amps output to a single antenna. Often done for banks of microwave radio amps, but the principal is the same for HF, and not too unwieldy in size at 10-11 meters because the coax can be neatly rolled up to reduce the footprint.

The Wilkinson Divider uses two 1/4 wave lengths of coax that join together like a Y (like a co-phase dual antenna harness). A resister is placed across the Y to help with impedance matching if needed and to absorb any reflected power that may occur (typically insignificant, often the resistors are not even used).

Since I am inexperienced, I want to include the resistors in case I foul up the calculations and hopefully avoid equipment damage or bothering the Fire Dept.

Obviously, the problem for the home experimenter is where to get the needed values of non-inductive resistance at such very high wattage ratings. That is why I haven't tried it for several years even though it is so simple. The salt water / baking soda dummy load looks like just the ticket to get the project off of a diagram and calculations scribbled on a napkin to the test bench.

The Wilkinson Divider is very interesting. Supposedly, the 1/4 wavelength elements provide a near infinite resistance to to currents trying to go the wrong way. That is why, when properly constructed, the resistors are often not needed in practice.

Whether it works or not, thanks again for the inspiration and collective wisdom.

Yum! pass me another jar of peanut butter.

[dime196604]

Well i decided to just plug it in and try it. Had a SWR of 1.7 from 1-40. Added a pinch more of salt, now have it down to 1.1 - 1.2 threw the band.

See easy enough. I didn't want to just hook my radio up the first time as well. But i did it and all was well. But i do keep an old RS radio i use for testing. Don't care if i hurt that one.