help on useing test equipment right

W

windtech

New Member

• Jan 15, 2011

• #1

OK i have a frequency counter. now I'm using this for RF. what probe setup do i need for this. or can i just use a scope probe set on 10x. measuring Chrystal's and such, mostly I'm well below 30 MHz. some around 10hrz. i know how to use a scope but this thing is new to me buy the way its a fluke 1900a

 

K

KMoffett

Well-Known Member

• Jan 15, 2011

• #2

10X scope probe should work OK.

Ken

 

MikeMl

Well-Known Member

Most Helpful Member

• Jan 15, 2011

• #3

KMoffett said:

10X scope probe should work OK.

Ken

Click to expand...

Assuming that the counter input is 1meg, with a similar input capacitance you would find on the Oscope vertical input.

 

K

KMoffett

Well-Known Member

• Jan 15, 2011

• #4

That Fluke has a 1M input, and most probes have an adjustment for capacitance. https://bama.edebris.com/manuals/fluke/1900a/ This doesn't mean that a 10X probe can't de-tune a circuit some, changing its frequency.

ken

 

Sceadwian

Banned

• Jan 15, 2011

• #5

Just keep in mind that when measuring crystal circuits even with a 10X probe you're loading the crystal slightly so the frequency you measure is not going to be 100% the same as when the scope probe isn't attached.

 

Mr RB

Well-Known Member

• Jan 15, 2011

• #6

I agree. If this is for Microcontroller PIC AVR etc timing applications, what I do is program the PIC with simple code that toggles an output pin every 256 cycles (ie in a 256 cycle timer interrupt so it is exact).

Then measure the freq on that pin with a frequency counter and any scope lead you like.