Updating the Featherweight Magnetic Switch

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I have used your magnetic switches in all of my bays and plan to continue. My biggest issue is I want to solder my wires and screw it down, which make the screw not sit flat. I have taken to looping the wire and soldering it so it forms a washer of sorts... It would be nice if there was room to solder the wire flat on the board (not through) that would be out of the way of the screw. So maybe a rectangular pad outside the area of the screw head.

Brian, I just use solder lugs to connect to the switch board. Very easy and secure. Heat shrink over the wired lug. Also, you can turn the lug out/up to avoid interfering with your mounting arrangement.

John
TRA #14574 L2
 
I just tested a prototype. This unit had about 7-10 mOhms of end-to-end resistance with 5.0 Amps flowing through That's a little higher than I had predicted but it includes solder and trace resistance. With 5.0 Amps current running continuously it was barely getting warm.

Even better news is that the standby current with the switch off is only about 2-5 micro-Amps. That's not much above the self-discharge rate of a small Lipo battery, so in theory you could leave it attached to a tiny 160 mAhr battery for a 6-month flying season and it would only discharge 10% more than it would if the battery were completely disconnected. I verified that 20V is o.k. on the input. Also, if you have the switch off and disconnect the power, it will remember to stay off if the power source is disconnected for over 45 seconds.

Note, this is with a sample size of 1 at room temperature, and the worst-case standby current performance from the spec sheets over temperature is worse than this, so YMMV.
 
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I have two projects right now that could use your magnetic switch, and one old style switch.... Let me know when you are ready to take new orders.
 
The production run shipped from the surface mount assembler today. This weekend I'll separate and test the new switches.

What were you referring to about the photobucket squeeze?
 
The production run shipped from the surface mount assembler today. This weekend I'll separate and test the new switches.

What were you referring to about the photobucket squeeze?

If you look at your posts, with pictures, there is an image that replaced your pictures which says "Please update your account to enable 3rd party hosting". Essentially photobucket are trying to force you to upgrade your account.

Can you confirm the final hole spacing for mounting? I am designing some new sleds now and need to send them into production but I want to use your new boards. Because my existing boards are the ones with "funky hole locations" that you had fixed I am not confident using them as a template.

Thanks.
 
If you look at your posts, with pictures, there is an image that replaced your pictures which says "Please update your account to enable 3rd party hosting". Essentially photobucket are trying to force you to upgrade your account.

Can you confirm the final hole spacing for mounting? I am designing some new sleds now and need to send them into production but I want to use your new boards. Because my existing boards are the ones with "funky hole locations" that you had fixed I am not confident using them as a template.

Thanks.
I see what you mean about PhotoBucket. Is there a free hosting service people prefer now?

The hole centers are 0.14" from each edge of the board, which is 0.54" x 0.72".
 
The updated switches are ready for sale. I have a handful of the original version that I will be selling first unless otherwise requested. So if you're about to place an order in the near future and would like the updated version just let me know in the order comments.


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