Howdy Guys,
Some of you may remember me from a prior circuit design thread that modulated the obstacle light ("ob Light") on a 42ft tower on my property at a residential airport. That project ran on AAC from Aug 2016 to Jun 2017 (https://forum.allaboutcircuits.com/threads/antenna-tower-obstacle-light-flasher-circuit.126328/ ) and I couldn't have done it without the fantastic help from AAC-regulars Crutschow, Doktor Jones, and several others. (THANKS AGAIN GUYS! That circuit is still working perfectly!) The purpose of the modulator was to apply a very slow sinewave to my tower's ob light that would get a pilot's attention but would not distract or blind that pilot like a strobe would. A side benefit of a slow sinewave is that the incandescent bulb's filament would last longer. I'm happy to say that it's been running for almost three years now on the original 2 bulbs!
Anyway, while that circuit activates an ob light on top of a tower, I now need a way for an inbound pilot to turn on/off the spotlights that illuminate our windsock on that tower. This is typically done by the pilot keying his/her microphone (breaking the squelch) 3, 5, or 7 times on a designated aviation frequency. After a preset time (usually 5 to 15 minutes), the ob and windsock lights would automatically shut down. (This is known in FAA-parlance as PCL, or Pilot Controlled Lighting. This kind of lighting control is very common at unattended airports or those with very few night ops.)
Back when we were working on the light modulator design, "hobbyist quality" PCL boxes (squelch-break detectors) were readily available from several sources. (Ramsey Electronics, Wag Aero, and Hamtronics, to name a few.) Unfortunately, now that I'm ready to purchase one, affordable ones have gone away, only to be replaced by "Major Airport-priced" systems! Sooooooo, here I am, back again with hat-in-hand asking for your help!
Back before Ramsey Electronics closed its doors, I purchased one of their AR2 Aircraft Receiver Kits and its companion AR2L Runway Lighting Controller Kit. However, I started hearing that Ramsey was in trouble (which would leave my kits unsupported if they folded) so I started looking at the Hamtronics R123 Runway Lights Controller. Unfortunately, Hamtronics has also since gone out of business. And while Wag Aero is still in business, they no longer offer their cheap ($750) lighting controller. Big-Airport, Commercial-grade lighting controllers ARE available but they run many thousands of dollars!!!
Sooooooo,
I figure that an old aircraft receiver can provide the frequency-specific input that I need for a homemade decoder that can count 3, 5, or 7 squelch breaks. The challenge would be designing the decoder to ignore squelch breaks that contain voice modulations.
About me: I was very active in military radar electronics many years ago so I'm not completely clueless. (Ignore what my wife says!!!) But while I still know the basics, I'm not up to date on all the new stuff that's out there. (But I CAN solder!!!)
Also, I'm sure that some well-meaning individual will point out that the FAA will undoubtedly have issues with a homemade lighting controller; however, the truth is that they won't because I live on a private airstrip. It would be different if this was for a Commercial airport but all the FAA cares about on private strips is that we follow accepted norms. In other words, don't use blue lights to mark a runway. (White lights are used to mark runways; whereas, blue lights indicate taxiways.)
Anyone up for a challenge???
Harvey
Some of you may remember me from a prior circuit design thread that modulated the obstacle light ("ob Light") on a 42ft tower on my property at a residential airport. That project ran on AAC from Aug 2016 to Jun 2017 (https://forum.allaboutcircuits.com/threads/antenna-tower-obstacle-light-flasher-circuit.126328/ ) and I couldn't have done it without the fantastic help from AAC-regulars Crutschow, Doktor Jones, and several others. (THANKS AGAIN GUYS! That circuit is still working perfectly!) The purpose of the modulator was to apply a very slow sinewave to my tower's ob light that would get a pilot's attention but would not distract or blind that pilot like a strobe would. A side benefit of a slow sinewave is that the incandescent bulb's filament would last longer. I'm happy to say that it's been running for almost three years now on the original 2 bulbs!
Anyway, while that circuit activates an ob light on top of a tower, I now need a way for an inbound pilot to turn on/off the spotlights that illuminate our windsock on that tower. This is typically done by the pilot keying his/her microphone (breaking the squelch) 3, 5, or 7 times on a designated aviation frequency. After a preset time (usually 5 to 15 minutes), the ob and windsock lights would automatically shut down. (This is known in FAA-parlance as PCL, or Pilot Controlled Lighting. This kind of lighting control is very common at unattended airports or those with very few night ops.)
Back when we were working on the light modulator design, "hobbyist quality" PCL boxes (squelch-break detectors) were readily available from several sources. (Ramsey Electronics, Wag Aero, and Hamtronics, to name a few.) Unfortunately, now that I'm ready to purchase one, affordable ones have gone away, only to be replaced by "Major Airport-priced" systems! Sooooooo, here I am, back again with hat-in-hand asking for your help!
Back before Ramsey Electronics closed its doors, I purchased one of their AR2 Aircraft Receiver Kits and its companion AR2L Runway Lighting Controller Kit. However, I started hearing that Ramsey was in trouble (which would leave my kits unsupported if they folded) so I started looking at the Hamtronics R123 Runway Lights Controller. Unfortunately, Hamtronics has also since gone out of business. And while Wag Aero is still in business, they no longer offer their cheap ($750) lighting controller. Big-Airport, Commercial-grade lighting controllers ARE available but they run many thousands of dollars!!!
Sooooooo,
I figure that an old aircraft receiver can provide the frequency-specific input that I need for a homemade decoder that can count 3, 5, or 7 squelch breaks. The challenge would be designing the decoder to ignore squelch breaks that contain voice modulations.
About me: I was very active in military radar electronics many years ago so I'm not completely clueless. (Ignore what my wife says!!!) But while I still know the basics, I'm not up to date on all the new stuff that's out there. (But I CAN solder!!!)
Also, I'm sure that some well-meaning individual will point out that the FAA will undoubtedly have issues with a homemade lighting controller; however, the truth is that they won't because I live on a private airstrip. It would be different if this was for a Commercial airport but all the FAA cares about on private strips is that we follow accepted norms. In other words, don't use blue lights to mark a runway. (White lights are used to mark runways; whereas, blue lights indicate taxiways.)
Anyone up for a challenge???
Harvey
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