Testing a Quark with Featherweight magnetic switch

TomSmith58

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I am attempting to test my Quark with the Featherweight magnetic switch. I read the manual and tested with only one jumper as per the instructions. I succeeded in testing the drogue side ok. The ematch fired as expected. However when I hook the battery up to test the main side the ematch fires the instant I attach the connector. When I hook the battery up the magnetic switch cycles to on. I am guessing that allows a power surge that fires the ematch. Is it the switch that is doing this ? I ordered some simple screw switches from MissileWorks because I suspect the switch is the culprit.

Thanks
Tom
 

Cl(VII)

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I am attempting to test my Quark with the Featherweight magnetic switch. I read the manual and tested with only one jumper as per the instructions. I succeeded in testing the drogue side ok. The ematch fired as expected. However when I hook the battery up to test the main side the ematch fires the instant I attach the connector. When I hook the battery up the magnetic switch cycles to on. I am guessing that allows a power surge that fires the ematch. Is it the switch that is doing this ? I ordered some simple screw switches from MissileWorks because I suspect the switch is the culprit.

Thanks
Tom

I had the exact same thing happen to me with a magnetic switch and a quark. Mine resulted in a scary/embarrassing moment at Airfest 2016 because I had my charges loads when I hooked up the battery...my sled left the prep table, and I nearly ruined my shorts. I assumed I had messed something up in the quark assembly, so it has been in my altimeter box since.
 

Worsaer

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The Featherweight mag switch starts in the ON state when power is applied. When connecting the battery, you need to be prepared with a magnet to switch it off.
 

djs

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The Featherweight mag switch starts in the ON state when power is applied. When connecting the battery, you need to be prepared with a magnet to switch it off.

I'm curious as to why this is. Seems like it would cause more problems this way?
 

Worsaer

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I'm curious as to why this is. Seems like it would cause more problems this way?

Here is Adrian's explanation from another thread when asked why default ON versus OFF...

Also consider that there is a safety downside to having the default state be off, namely that if someone has a brownout due to charges firing or a temporary battery power disconnection in flight (not all that uncommon), having the switch turn on when power is re-applied could prevent a lawn dart. For ground safety, the best practice for this switch is to connect the battery and then turn the switch off before connecting charges. That way the altimeter need never be on with charges connected until you get to the pad. The switch can stay off for weeks while connected to the battery, so that provides a lot of flexibility in how and when the av-bay preparation is done.

-Adrian
 

Adrian A

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I had the exact same thing happen to me with a magnetic switch and a quark. Mine resulted in a scary/embarrassing moment at Airfest 2016 because I had my charges loads when I hooked up the battery...my sled left the prep table, and I nearly ruined my shorts. I assumed I had messed something up in the quark assembly, so it has been in my altimeter box since.

So without a magnetic switch, if you have charges connected to a Quark and then plug in a battery, does the charge go off?
 

Cl(VII)

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So without a magnetic switch, if you have charges connected to a Quark and then plug in a battery, does the charge go off?

Never tried. Haven't had a problem like this with any other altimeter, and I use mag switches exclusively. My bench is overwhelmed with other stuff right now, but I'll test it at some point. Like I said, I assumed my assembly was the problem.
 

cerving

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Sounds like you got a dead short on the main channel power transistor... check your soldering very carefully. I HIGHLY recommend testing any configuration with Christmas tree lights before you try to fly it. BTW, the magnetic switch should not be a problem... I know several people that fly them that way. Just have the magnet handy to turn it off right after you connect the battery.
 
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