[NLRS] RF Frequency Counters

[John P. Toscano]

Hello out there.  I'm looking for an opinion (or several) from the group 
on RF frequency counters.

What I have now is a real inexpensive Radio Shack model that tops out at 
about 1300 MHz (practically DC for some of you folks).  I am interested 
in something that will work at least up through the 10 GHz ham band, 
with good accuracy.

I'm looking at a used HP 5342A microwave frequency counter with Option 
001 (high-stability timebase) and Option 002 (amplitude measurement) 
installed.  It has two inputs, Input 1 rated at 10 Hz to 520 MHz, and 
Input 2 rated at 500 MHz to 18 GHz.

If anyone has experience with this model (good or bad), or has better 
suggestions, I'd like to hear them.

Also, I'm wondering about accuracy, i.e. what is reasonable resolution 
at 10368.1 MHz?  The specs on the Option 001 say:
       Aging rage: < 5e-10 per day after 24-hour warmup
      Temperature: < 7e-09 over the range of 0C to 50C
       Short term: < 1e-11 for 1 second average time
   Line variation:   1e-10 for 10% change from nominal
          Warm-Up: < 5e-09 of final value 20 min after turn on, at 25C

The specs say that ACCURACY is +/- 1 count, +/- time base error.  The 
time base (internal or external) is 10 MHz.  I can't believe that they 
mean what (I think) this says, i.e. if the time base is accurate to 
1e-10 (for example), times 1e6 Hz, that the time base is accurate to 
1e-4 Hz and therefore the display at 10 GHz is also accurate to 1e-4 Hz, 
plus or minus 1 display digit.  I would think, that at best, if the time 
base was accurate to 1e-10 (for example), that 1e-10 x 1.3681e11 would 
be 1.3681e1 HZ or 13 Hz, plus or minus 1 Hz on the display, or +/- 14 
Hz.  The problem is that they don't seem to state the ACCURACY of the 
timebase anywhere, only its stability.

The meter has 11 digits, and can DISPLAY 10 GHz to a resolution of 1 Hz, 
but I wonder what the true ACCURACY is.  The specs above only talk about 
stability, but who cares if it is stable to 1e-11 if it is 10 MHz off 
frequency?  Obviously, my need to measure 10 GHz to 1 Hz accuracy is 
limited, but I want to do a whole lot better than being 10's of KHz off 
frequency like I am now, based on the IF rig readout.  (Yeah, I do know 
how to subtract, but the apparent offset is so odd that it can be a 
challenge to do in my head under pressure, and I'd rather not have to!)

Supposedly, the instrument I'm looking at has been calibrated against a 
GPS-locked OCXO.  It also has an external timebase input, and I have 
(but have not yet put together) a GPS-disciplined OCXO that could 
potentially be attached.  Is it likely to be worth the effort?

Thanks in advance for your collective wisdom.

John (W0JT)