Jumper for 125MHz

[luky315]

I need something to manually select between 2 clocks, one of them is 50MHz and the other one 125MHz. I have never used a classic 3 Pin header with a jumper for this frequency range, but I am expecting problems. So what would be a simple, mechanical alternative which performs better?

[tooki]

I doubt it’ll be a problem, 125MHz isn’t all that fast.

Alternatives/variations:

-headers and jumpers smaller than 2.54mm pitch
-small SMD DIP switch
-small SMD SPDT slide switch
-solder jumper
-simple circuit using jumpers to control some logic gates to select the clock electrically

[PCB.Wiz]

I need something to manually select between 2 clocks, one of them is 50MHz and the other one 125MHz. I have never used a classic 3 Pin header with a jumper for this frequency range, but I am expecting problems. So what would be a simple, mechanical alternative which performs better?

Why do you expect a 3 pin header to be a problem ? It's not 125GHz.
You could always pay a little bit more, and go for a 2mm jumper, which has a smaller footprint. You can even buy 1.27mm shunts/jumpers.

[moffy]

If using a jumper, which should be fine, you might want to surround the header with ground plane, to reduce emissions. The 125MHz is not that high but the edges are pretty fast if we are talking square wave/logic signals.

[SiliconWizard]

It shouldn't be a problem unless the jumper itself is really loose.
One problem I see with that though, if you're using TH jumpers, is the antenna effect of the pin header. Outputting a clock on a pin header can ruin EMC. Done and tested.
So I would favor a solder jumper.

[Terry Bites]

CK make a nice little switch TDD01H0SB1R, will you feel the benefit. Probalby not.