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-   -   Single Landing Light Flasher? (not wing wag) (https://vansairforce.net/community/showthread.php?t=13191)

BruceW 12-04-2006 09:35 PM

Single Landing Light Flasher? (not wing wag)
 
I have a single landing light and want to add a flasher to
the electrical system. I read somewhere that the
"wing wags" will burn out if you attach them to
only one light.

Any single light "flashers" that are recommended???
Thanks.

Bruce W.

svanarts 12-04-2006 10:04 PM

I put one of these on my RV-4 to flash my landing lights. Been in there for two years with no problems.

B and C Specialties Solid State Flasher

Forgot to say and it should work just fine on one bulb. Just modify the schematic B and C has on their web site.

Bryan Wood 12-04-2006 10:17 PM

Quote:

Originally Posted by BruceW
I have a single landing light and want to add a flasher to
the electrical system. I read somewhere that the
"wing wags" will burn out if you attach them to
only one light.

Any single light "flashers" that are recommended???
Thanks.

Bruce W.

You might measure the resistance of your landing light bulb and put a resistor with the same resistance on the other output of the wig wag. The wig wag won't know there isn't a bulb there. So that you don't have to do a bunch of math to come up with a wattage just go with something kind of big like a 3 watt resistor and it should work out.

Regards,

az_gila 12-04-2006 10:59 PM

Add the resistor
 
Quote:

Originally Posted by Bryan Wood
You might measure the resistance of your landing light bulb and put a resistor with the same resistance on the other output of the wig wag. The wig wag won't know there isn't a bulb there. So that you don't have to do a bunch of math to come up with a wattage just go with something kind of big like a 3 watt resistor and it should work out.

Regards,

This resistor will also prevent the needle of your ammeter (if you have an old fashioned analog one... :) ...) wiggling and distracting you...

Bryan's power calculations are a little bit shy.... ;)

If you have a 100 watt landing light bulb, a 1.2 ohm resistor should do it... needs to be about 50 Watts though (100 watts - same as the landing light, but with a 50% duty cycle, makes it 50 watts dissipated in the resistor).
I would use two 2.4 ohm resistors of 25 watts each in parallel to get the 1.2 ohms...

Mouser has them cheap... bottom right of this page...

http://www.mouser.com/catalog/628/526.pdf

gil in Tucson

Grumman does this with the old fashioned red flashing quartz bulb on top of the rudder...

Bryan Wood 12-05-2006 12:57 PM

Quote:

Originally Posted by az_gila
This resistor will also prevent the needle of your ammeter (if you have an old fashioned analog one... :) ...) wiggling and distracting you...

Bryan's power calculations are a little bit shy.... ;)

If you have a 100 watt landing light bulb, a 1.2 ohm resistor should do it... needs to be about 50 Watts though (100 watts - same as the landing light, but with a 50% duty cycle, makes it 50 watts dissipated in the resistor).
I would use two 2.4 ohm resistors of 25 watts each in parallel to get the 1.2 ohms...

Mouser has them cheap... bottom right of this page...

http://www.mouser.com/catalog/628/526.pdf

gil in Tucson

Grumman does this with the old fashioned red flashing quartz bulb on top of the rudder...


Gil,

Yeah, I didn't do any math, just a weak guess.

http://www.angelfire.com/pa/baconbacon/page2.html

Best,

mlw450802 12-05-2006 01:19 PM

Quote:

Originally Posted by Bryan Wood
Gil,

I'm missing something here. If one channel has a 100 ohm light on it, placing a 100 ohm resistor to simulate a like bulb on the other output would require a 1.44 watt 100 ohm resistor. It is basic ohms law. I=E/R or 12/100 to find current. Then I squared R to get power. 12/100=.12
Square .12 and get .0144. Multiply times 100ohms = 1.44 watts. Here is an ohms law calculator that you can use to check the math. Using a smaller resistor (physically) will keep you from having to do a new weight and balance afterwards. :D

http://www.angelfire.com/pa/baconbacon/page2.html

Best,

Bryan, you mixed up the ohms and watts. The bulb is 100 watt. Power = E^2/R so R=E^2/100.

R= 144/100 = 1.44 ohms.

-mike

Bryan Wood 12-05-2006 01:36 PM

Mike, You were to quick! I realized my mistake and couldn't fix it as fast as you were able to correct me on it. Anyway, with the above calculator you can enter the 100W and 12 volts to come up with the resistance in the bulb quickly. Then you can do the same to figure the resistor value and wattage needed. Oops!!! The point of the original post was to suggest using a resistor and I was busily watching deal or no deal on tv. Your right that I locked in on the 100w thing and reading it as if Gil was implying the lamp had a 100 ohm filiment. This locked me up because it just didn't compute. My mistake.

Best,

Jekyll 12-05-2006 03:33 PM

Quote:

Originally Posted by BruceW
I have a single landing light and want to add a flasher to
the electrical system. I read somewhere that the
"wing wags" will burn out if you attach them to
only one light.

Any single light "flashers" that are recommended???
Thanks.

Bruce W.

Bruce:

Contact Eric Jones at Perihelion http://www.periheliondesign.com/
Eric can easily modify his wig wag for 1 light.

Jekyll

Tom Maxwell 12-05-2006 06:49 PM

Auto Equipment
 
Is there some reason we can't just use an auto emergency flasher? I don't know, maybe the auto manufacturers have gone to a solid state flashing system by now. It just seems to me that some of these auto systems could be used in non-critical flight systems for less cost.

BruceW 12-05-2006 10:15 PM

Thanks for the replies
 
See, that's why I love posting on this site. There is no way I could have figured out the electronics math. You guys are great. I barely know an ohm from a watt. I'll take your posts to the local aeroelectric expert who will translate for me. I understand the "put a resistor on it" part, just which one. Thanks again.

Bruce W.


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