Pedals2Paddles
Cleared for Takeoff
This is hanging down under the panel of a C150G. Any guesses? I have a feeling whoever did avionics work on this thing in the past was a moron.
Hyper-drive variac or a modulator for the di-lithium crystals.
"Where's the kaboom? There was supposed to be an earth-shattering kaboom!"
Well I haven't tried turning it with the big red switch turned on yet. I was busy with some other things and figured maybe I'd ask first. However I have a feeling everyone here's guess will be as good as mine with this silly thing.
What seems exceptionally stupid is that the only actual connected wires are on the outer two pins. On most potentiometers, those two cancel eachother out. You would always wire it in with an outside and center pin. So theoretically, the way it is wired, it actually does nothing at all.
Why do pictures like that always seem to come from a 150?
Well I haven't tried turning it with the big red switch turned on yet. I was busy with some other things and figured maybe I'd ask first. However I have a feeling everyone here's guess will be as good as mine with this silly thing.
What seems exceptionally stupid is that the only actual connected wires are on the outer two pins. On most potentiometers, those two cancel eachother out. You would always wire it in with an outside and center pin. So theoretically, the way it is wired, it actually does nothing at all.
Actually, the way it's wired it is a fixed resistor. Probably 150K ohm as that is a very common value. Why that was needed there and why somebody had a pot and didn't have a regular resistor I have no idea. But if you are correct on what's wired, you are correct in that turning the shaft will make no difference.
John
I will bet anything that this plane was owned by a HAM at some point. Here's a guess, that resistor is needed in the microphone circuit to deal with modern mics. He knew he needed a 150k Ohm resistor and that was the one he found in his pocket with his change, so that's the one that went in.
As a ham myself, I resemble that remark.
Except I'm < 100 yrs old
It's most likely a dimmer for the light on something - perhaps a radio or transponder? Not the whole panel or anything that draws a lot of current.
Volume control for something would be the distant second guess.
What seems exceptionally stupid is that the only actual connected wires are on the outer two pins. On most potentiometers, those two cancel eachother out. You would always wire it in with an outside and center pin. So theoretically, the way it is wired, it actually does nothing at all.
Probably 150K ohm as that is a very common value.
If that is a 10 watt wirewound as I suspect that it is, getting much above 5 or 10k ohms is going to be difficult as that is a LOT of hairfine wire, even nichrome, and large resistor values and high wattage don't go hand in hand.
And I resemble the ham comment. We can be as clean and neat or as slobby and haywire as the next guy. I'll show you a sanitary 2 meter installation next time I take pictures of the airplane and I defy you to find the antenna installation.
Jim
I'm not saying that it's impossible to beat genetics, after all, Gingers exist, but a Pilot and a HAM has two genetic strikes on the 'Cheap' board. If he has a sailboat too, he is genetically destined to do things as pictured.
That would be
Thanks,
- 1750867CFI A&G, IA
- WX6RST Extra
- Sail #422 Catalina 22
Jim
I dunno, that looks awfully like a 10 watt wirewound pot. That SHOULD take a whole lot of panel lights. Wouldn't probably use this hefty of a pot on volume unless I was controlling speakers on a rock band.
Jim