[time-nuts] HP53132A vs SR625

Hui Zhang ba6it at 163.com
Fri Mar 15 23:33:30 EDT 2013

Hello SAID:
  I am very sorry I almost missed this email in my inbox, and say sorry for reply so late, and I am very appreciate you wrote so many useful word for me.  I answred your in quote part in this email. Thanks a lot.

  After a short consideration, finally I bought SR625, now it on my workbench, I am very satisfied with its work.

  I still have few quesiton:

1) When I use long gate time to mesure fequency (like as 10s or more), the STOP LED in channel B will light up, at moment in the reading result, the STOP will off few second, and light up again, is this normal?

2) When I use TI mesurement function, I connect GPS's 1PPS to CH1 and use a BNC tee split signal with 1.5m cable to CH2, in the TIME mode, I saw the 999999990xx etc, if I changed cable length the reading will change, what mean of this reading?

>rent one of each if you can before you make your choice. I have both, and  
>the HP unit is much easier to use once you know which button sequence to 
>push to  get more than just "Frequency/Time-Interval" type measurements - these 
>can be  single-button events on the HP unit.
>Even offsetting and normalizing frequencies becomes very easy after a  
>couple of days of using the unit, there is no setting that takes me longer than  
>about 5 seconds to set up, so while not perfect, the user interface can be  
>learned easily. I find the SR620 to have too many buttons(!) I always find  
>myself searching for just that one button. Anyways, more buttons are just 
>more  things that can fail. If you are a pilot, and have used a Garmin 430W  
>GPS in your life, then the HP user interface is no challenge whatsoever and  
>seems very easy to use..
>The SR-620 has it's advantages, especially when you just do one single type 
> of measurement, but for me it has a huge number of disadvantages, and I 
>mostly  use the 53132A for that reason:
>1) I paid quite a bit of money and I had it "calibrated" and fixed by SRS,  
>and it still exhibits a significant frequency offset with a "perfect" 
>reference  and "perfect" DUT!!!

>SRS says a small frequency error is "normal", well that prevents me from  
>using the unit as a frequency counter, for me it's only useful as a relative  
>display frequency counter. HP doesn't have such a frequency error, so no  
>worries there.

I will pay attention and observe those problem....
>2) The SRS unit is soooo loud that it's totally annoying and unacceptable  
>for long measurements. Many folks reported this here before. It's just bad.  
>Whining like crazy.

Indeed this is little problem but really troube me.
>3) The SRS unit is 19" wide, huge, heavy, and clunky. I need my  counter 
>portable, only the HP unit will do

No problem, I like huge and heavy device, they are usually reliabe.
>4) The SRS unit has a much lower MTBF because of all the parts inside, and  
>it needs finicky adjustments, see item 1) above. The HP unit either works, 
>or is  just dead. Not much to adjust. Different technology generation. And 
>the coolness  factor: a nice florescent tube display is so much more modern 
>looking than those  clunky old 7-segment LED's..

Yes I agree you, the SR625 is 90's product, sort of old and vintage, I am very worry about his lift. The only thing I can do it pray god I can have good luck. 
>5) The SRS unit is usually $1000 more than the HP unit, and you don't know  
>how good the unit is you are buying because of all of the calibration 
>stuff.  Usually there is no hit-or-miss issue with the HP units, they either 
>work, or  are dead.

My SR625's price not bad, very close with HP53132, although it's old. I hope it can work five to ten years that I will be satisfied.
>That said, the HP unit doesn't measure well at 10MHz, so I mostly use a  
>divide-by-two to get one more digit of resolution out of it, and it's time  
>interval resolution is not as good as the SR620. But for time interval  
>measurements I use a Wavecrest DTS unit that blows the SR620 and the HP out  of 
>the water anyways..


>>In a message dated 2/7/2013 16:39:04 Pacific Standard Time, ba6it at 163.com  

>>Hello  Dear Group:

>>I am very glad to see so many replies in  the morning, and I am very 
>>grateful to every time nuts gave me useful  information, your proposal has 
>>strengthened my determination, in fact, I am  also very like SR625, So I will to 
>>find and buy a good shape SR625 for my new  time interval measure instrument.

>>Thanks again for everyone's  advice, which is very useful to make a choice 
>>for me. Sorry for not reply  everyone's mail. 

>>Best Regards!

>>Hui  Zhang
[time-nuts] HP53132A vs SR625

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