Testing two H-P Microwave Frequency Counters Added To Lab and Field Instruments Inventory

Over the past few days, I’ve added two Hewlett-Packard frequency counters to the list of test instruments for use at the lab bench and in the field. Both can measure both frequency from a range of 10 Hz up to well into the microwave range, and will measure signal levels as well.

H-P 5342A Microwave Frequency Counter. This one measures from 10 Hz to 18 GHz, and measures signal levels as well.
H-P 5347A frequency counter. Measurement range 10 Hz to 20 GHz, including signal level display.

Testing Frequency Accuracy On 11/20/21

To test and verify accuracy of both instruments, I set them up on the bench, allowed them to warm up properly, and utilized my 10 MHz GPS Disciplined Oscillator (GPSDO) as both an external frequency/clock standard.

10 MHz GPSDO, built by myself and a friend. This is the device which makes sure that the accuracy of the frequency reference for instruments in the lab are traceable to NIST standards, since the GPS satellites are all synchronized to the NIST/atomic clock sttandard.

I also used the GPSDO as a 10 MHz external clock reference for my TPI-1005-A test signal generator.

The TPI-1005-A signal generator can produce signals in the range of 35 MHz to 4.4 GHz.

For purposes of testing the two frequency counters, I chose to use a signal of 4.0 GHz.

TPI-1005-A set for a frequenc of 4.0 GHz.

Here are the test measurement results for the two frequency counters.

The 5242A measured precisely 4,000,000,000 Hz — precisely 4.0 GHz with no error all the way down to the 1 Hz position.
The 5347A measured exactly 4,000,000,000 Hz as well, also accurate all the way down to the 1 Hz position.

In summary, both instrument showed extremely precise frequency measurements and will be well better than the required frequency tolerances necessary for all the types of equipment which I maintain for clients. I’m very pleased with how well both of these frequency counters perform, especially for instruments which were built back in the 80’s to 90’s. Hewlett Packard test equipment is built like a tank and holds up well to decade after decade of use if treated well.

I will be periodically running these same performance and confidence tests on these two instruments, just as I do with other equipment in the lab such as spectrum analyzers, etc.