Switch-Jack FAQ
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Frequently Asked Questions...
about Switch-Jacks and Micro Switch-Jacks

Is a Switch-Jack as reliable as the standard slide switch that comes with my radio?
Most of the time, yes it is. There is no way to qualify your particular slide switch for a fair comparison. Slide switches have the unique advantage of having built in wiping action, every time they are switched on or off. This cleans the contacts. Some slide switches are junk however, and fail during flight. You would do better to give up the wiping for the high quality metal contacts and high current capability of the Switch-Jack. When properly cleaned and cared for, the Switch-Jack is extremely reliable. I would guess that a slide switch that comes with a JR 10 channel radio is pretty good, and one that comes with a Tower Hobbies 2 channel/2 stick is not so good. In either case, you will still need a way to charge your batteries, right? Get a Switch-Jack!

Should I use the the Switch-Jack or the Micro Switch-Jack?
This depends on your application. If you are using more than 2 servos in your plane, use SJ. If your airborne radio will draw more than 1 amp at full load (peak), use Switch-Jack. If you are cliff flying EPP foamie combat wings and crash accidentally every 10 minutes, use SJ. But, if you are seeking to reduce your plane's weight by a couple grams and have the very smallest volume possible, and have a peak current load of <1 amp at 6vdc, then you can use the Micr Switch-Jack. With that said, some people are using the MSJ in slope planes, combat and 4 channel HLGs with no problems. It is a tough little bugger, but Hollyday Designs will not overexaggerate the current rating capability of the MSJ. Your mileage may vary. We intend to do some real world torture tests on both SJ and MSJ and we will publish the results online.

Is the Switch-Jack available with the cool anodized aluminum handle on the plug, like the Micro Switch-Jack?
No, only red plastic is available. This is a cost savings of $2! If plastic were available for MSJ, we would specify that instead of the standard metal. But is cool... ;)

What are the technical Specifications of the Switch-Jack?
Jack (flying) weight 5 grams
Jack dimensions 0.828 Length, 0.430 Max. Diameter (inches)
Fuselage hole size 0.313 inches; fuselage wall thickness up to .125 inches
Jack configuration 2 conductor jack, with sleeve shunt spring switch
Split center pin shaped to hold mating plug firmly. Adjustable for plug tension!
Plug contact dimensions .375" long, 0.218" diameter sleeve, 0.99" center hole
Jack hole dimension .226" diameter
Life 10,000 insertion/withdrawal cycles minimum
Operation force 3 pound insertion (maximum), 4 ounce withdrawal (minimum). Adjustable with a small paper clip!
Contact Resistance 0.01 ohms maximum (initial),
0.02 ohms maximum (after humidity, durability exposure)
0.1 ohms maximum (after salt spray)
Jack and plug are tested to mil-std 202 method 101d, condition b (48 hours) salt spray
Dielectric Withstanding Voltage 500 VAC maximum
Contact Rating 5.0A, 12VDC resistive
Jack terminal soldering spec: 485°F for for 5-7 seconds
Housing: Molded plastic
Mounting Bushing and Hex Nut Plated copper alloy
Pin, Spring and Terminals Plated copper alloy
Insulators Rigid plastic

What are the technical Specifications of the Micro Switch-Jack?
Jack (flying) weight 1.3 grams
Jack dimensions 0.505" overall length, 0.350" width, 0.515" height (including terminals), 0.306" height (with terminals bent away)
Fuselage hole size 0.203 inches; fuselage wall thickness up to .062 (1/16") inches
Jack bushing threads #10-48
Jack configuration 2 conductor jack, with sleeve shunt spring switch
Plug contact dimensions 0.096" diameter, 0.450" length
Jack hole dimension 0.100" diameter
Life 10,000 insertion/withdrawal cycles minimum
Operation force 11 ounce insertion (minimum), 11 ounce withdrawal (minimum).
Contact Resistance 0.01 ohms maximum (initial),
     0.10 ohms maximum (after Humidity: Per MIL-STD-202, method 106.)
     0.10 ohms maximum (after Salt Spray: Per MIL-STD-202, method 101.)
Dielectric Withstanding Voltage 500 VAC maximum
Contact Rating 1.0A, 6VDC resistive. Original rating is 1.0A at 12VDC. Manufacturer would not generate new current spec at 6vdc for a small peanut like me. This a very conservative continuous current rating for this high quality jack. It can handle two micro servos and receiver current easily.
Jack terminal soldering spec: 485°F for for 5-7 seconds
Housing Glass reinforced plastic
Mounting Bushing and Hex Nut Nickel plated copper alloy
Tip Spring, Shunt Terminal, Sleeve Terminal Silver plated copper alloy