[Test-Equipment] Testing HP Sensors?

[Marco IK1ODO]

Hi Ted,

The 8484A should be ok. I don't remember using it specifically with 
the 435A, but the 435B has interchangeable scales on the range knob; 
one of those scales was for the ordinary +20dBm sensors (8481A, 
8482A, 8485A, etc), another one for the hi-send ones like the 8484A, 
and there was a third to be used with the 3W sensors. So a 40dB 
offset is very like. The usual fault for the 8484A is a damaged 
diode, so you would have low sensitivity, not a 10dB excess.

There is a lot of literature on those sensors on the agilent web 
site; I suggest that you have a look at it, probably you will find a 
cal procedure to be used with the 435A. Otherwise let me know, 
tomorrow at QRL I will check what I have on paper.

73 - Marco IK1ODO


At 20.12 06/12/2006, you wrote:
>On Fri, 24 Nov 2006 19:48:12 +0100, Marco IK1ODO wrote:
>
> >There is a lot of electronics inside. Better to borrow a 435A or 436A
> >from a friend and do a zero and cal test. If it works I need one 8482A
>
>Hi Guys:
>
>Well, I borrowed a 435A (unknown S/N.....I didn't check before
>the owner had to leave) to test the 8482A and 8484A RF sensors.
>
>This is what happened:
>
>The 8482A calibrated just fine to 1mW.
>
>Using the 30 dB pad with the 8484A gave wierd results.
>Upon applying the test signal (1mW at 50Mhz), I had to
>set the 435A to the 10mW scales to calibrate?
>
>After reading, reading and more reading, it looks like
>the 435A needs option 002, which is a different range
>knob for use with the 8484? Could it be that simple?
>
>The more I think about it, the 30 dB pad would provide
>a 1 microWatt signal into the sensor, but the 435A
>doesn't have a 1 uW full scale setting, so how could
>it be calibrated using the supplied range scale?
>
>I also tried using my IFR 1500 service monitor as a
>signal source, but the attenuator is so noisy that a
>stable signal couldn't be had, although the 435A did
>go up and down as the IFR's attenuator was moved.
>
>Does this sound like the sensor is OK?
>
>Thanks a bunch,
>
>
>Tedd Doda, VE3TJD
>www.ve3tjd.com
>
>Lazer Audio and Electronics
>Baden,