Radio Shack 220-306 frequency counter -- fried?
 

I bought one of these last year and it worked OK for RF measurement.

I am now for the first time trying to use it to measure the [digital]
frequency at a chip pin. I set it for CMOS/TTL range. It reads 4.9
MHz open circuit and shorted out. Sometimes it reads zero. Nothing
changes when I test the chip pin. I get the same result using an
oscilloscope probe and solid copper leads.

There is supposed to be a 5KHz signal at the pin. I can hear a tone
roughly of that frequency (very high) when I put that pin on the
input of an amplified speaker.

Is my meter fried? Or am I doing something wrong?

Ken KC2JDY


Ken
(to reply via email
remove "zz" from address)