Piper nav light switch/dimmer rheostat

Sac Arrow

Sac Arrow

Touchdown! Greaser!
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Snorting his way across the USA
These appear to be hard to find. Anybody have a source? Arrow II.
 
wentworth call 1800wentworth have the correct part # than you might get good service and price
 
Sac Arrow said:
These appear to be hard to find. Anybody have a source? Arrow II.
Click to expand...

The updated electronic ones are going to be a LOT cheaper in the long run. Chief has them as well as a few others ... I don't have my Spruce catalog handy.

Mouser Electronics still sells the old fashioned rheostat if you've got a resistance and power spec. Their current online catalog page 914 lists the physical dimensions of their rheostat line. Go to

http://www.mouser.com/Passive-Components/Potentiometers-Trimmers-Rheostats/Rheostats/_/N-9q0yj/

and then jump from any of the listed parts to catalog page 914.

Of course, if you have to have Mr. Piper's signature on it ... good luck.

Jim

.
 
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weirdjim said:
The updated electronic ones are going to be a LOT cheaper in the long run. Chief has them as well as a few others ... I don't have my Spruce catalog handy.

Mouser Electronics still sells the old fashioned rheostat if you've got a resistance and power spec. Their current online catalog page 914 lists the physical dimensions of their rheostat line. Go to

http://www.mouser.com/Passive-Components/Potentiometers-Trimmers-Rheostats/Rheostats/_/N-9q0yj/

and then jump from any of the listed parts to catalog page 914.

Of course, if you have to have Mr. Piper's signature on it ... good luck.

Jim

.
Click to expand...
Got more details on the electronic version?
 
weirdjim said:
The updated electronic ones are going to be a LOT cheaper in the long run. Chief has them as well as a few others ... I don't have my Spruce catalog handy.

Mouser Electronics still sells the old fashioned rheostat if you've got a resistance and power spec. Their current online catalog page 914 lists the physical dimensions of their rheostat line. Go to

http://www.mouser.com/Passive-Components/Potentiometers-Trimmers-Rheostats/Rheostats/_/N-9q0yj/

and then jump from any of the listed parts to catalog page 914.

Of course, if you have to have Mr. Piper's signature on it ... good luck.

Jim

.
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I don't really care what goes in, as long as it works. Is it a drop in replacement?
 
Yeah, that POS switch. I had one go out in the Warrior, it was a PITA to put in there. My updated technique is to click it on, which turns on the the nav lights, and leave it there all the time, so the wheel doesn't wear out. I've had my Arrow since '13 and the last time I touched that thing was the day I bought it. Light bulbs are cheaper and easier to replace than the rheostat :D
 
Has your A&P changed the transistor in that circuit?
 
I might have a left over one sitting in my hangar. I'd have to look though.
 
Just bought the entire assembly (two rheostats) for my Lance for $50 on eBay...keep your eyes open and you can find plenty of good items on there.
 
New rotary switch available from airparts west. $325 now. A piper switch. Just the way it is on a certificated airplane. If you whine and go with an STCd dimmer from max dim, you’d still need to install an on/off for the nav lights as the rotary would only control the panel lights. By the time you’re done with that, you’ve had to lengthen wires, cut holes, label the new switch etc. Just buy the right part and be done with it.
 
Charlie S. said:
New rotary switch available from airparts west. $325 now. A piper switch. Just the way it is on a certificated airplane. If you whine and go with an STCd dimmer from max dim, you’d still need to install an on/off for the nav lights as the rotary would only control the panel lights. By the time you’re done with that, you’ve had to lengthen wires, cut holes, label the new switch etc. Just buy the right part and be done with it.
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Gonna have to agree with the newbie here..... Nice first post too...
 
Charlie S. said:
New rotary switch available from airparts west. $325 now. A piper switch. Just the way it is on a certificated airplane. If you whine and go with an STCd dimmer from max dim, you’d still need to install an on/off for the nav lights as the rotary would only control the panel lights. By the time you’re done with that, you’ve had to lengthen wires, cut holes, label the new switch etc. Just buy the right part and be done with it.
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Welcome to PoA. I agree, in my short time as a plane owner, I've found that "just do it right the first time" ends up being cheaper.
 
EppyGA said:
Has your A&P changed the transistor in that circuit?
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Better question: Has he taken his voltmeter and measured the potentiometer's output and the voltages at the transistor? Too many just start replacing parts with no real idea of what is needed. It gets expensive.
 
@Sac Arrow

A Long time ago,
at an airport far far away (in CA)
A part was needed....

What did you do?
 
Ravioli said:
@Sac Arrow

A Long time ago,
at an airport far far away (in CA)
A part was needed....

What did you do?
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I'm sure he is still looking.... Its a hard part to find! I didn't even see the date on the post.... Hell, I even sent Sac a PM with a guy I know. :blush:
 
I split it and went with a switch for the nav lights, and a separate rheostat for the panel lights. Had panel space to do it. Was WAY cheaper than the $325 quoted above, even with labor.
 
Ravioli said:
@Sac Arrow

A Long time ago,
at an airport far far away (in CA)
A part was needed....

What did you do?
Click to expand...

That was a long time ago, but the A&P was able to get a hold of one. They were a Piper Service Center so I guess they had some ins.
 
Most likely suspect is the transistor for the dimmer. These are cheap but your A&P may need to remove some radios to get to the transistor. If it is a bad rheostat, I suggest that you replace with one of the Max dimmers https://www.aircraftspruce.com/catalog/elpages/maxDimUnit.php. It will be cheaper to install and will replace the 30-year old technology with new and better suited as an LED dimmer.
 
I fabricated a solid state dual dimmer to replace the rheostat in my C172D and had it approved on a 337 by the KOAK FSDO. It still works great after 20 years. It was dirt cheap to build. It's safer, uses less power, and is more reliable that a rheostat.

Dual Dimmer Schematic med.jpg Dual Dimmer Photo.jpg
 
Stan Cooper said:
I fabricated a solid state dual dimmer to replace the rheostat in my C172D and had it approved on a 337 by the KOAK FSDO. It still works great after 20 years. It was dirt cheap to build. It's safer, uses less power, and is more reliable that a rheostat.

View attachment 96084 View attachment 96085
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Nicely done. What's the diode bridge for? Doesn't show in the schematic.
 
Dan Thomas said:
Nicely done. What's the diode bridge for? Doesn't show in the schematic.
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Good question, Dan. It's for a separate application unrelated to the dimmer circuitry. It was just a convenient place to mount the bridge and provide a heat sink for it.
 
Suspect it's the transistor as well, but you can often find the entire switch/dimmer assembly on ebay, texas air salvage, flying fish air parts and the like.
 
frtrkap said:
Suspect it's the transistor as well, but you can often find the entire switch/dimmer assembly on ebay, texas air salvage, flying fish air parts and the like.
Click to expand...

Hi-- can anyone provide guidance on proper troubleshooting the circuit? e.g., what voltage to expect across what segments (input/output of Q1/Q2 and R1/R2, etc.)? I have a PA-28-235, SN 28-7310091. Thx.
 
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