How can I read data(amlitude signal) from spectum analyzer HP8563E Using GPIB NI-488.2AND labview 6.

[digital]

How can I read data(amlitude signal)and dispaly graph from spectum analyzer HP8563E using GPIB NI-488 and labview 6. DO you have VI application ready to send it to me.

Thank you for your help.

[Dennis_Knutson]

There's a driver that you can download at the instrument driver network at http://www.ni.com/devzone/idnet/default.htm. Or you can get it off the instrument driver CD that comes with LabVIEW.

[RayFarmer]

Hi,

Dennis is correct, you can get the driver off the NI site.

Open the HP8563E Getting Started.vi which will allow you to obtain various measurement as well as obtaining the trace and plotting to a chart.

To obtain a measurement such as amplitude you have to set a marker to the frequency of interest and then read off the marker dtails such as the amplitude. Look at HP8563E Query Amplitude.vi.

The HP8563E Query Trace Array.vi returns your trace data.

Hope this helps
Regards
Ray Farmer

[digital]

Thank you very much for you help.

Now I want to read signal amplitude along distance from analyzer.

So how can I put the frequency sampling of the signal of interset. Then I want to save amplitude and distance in Excel file.

Regards,

[digital]

Hi,

I tried to use just HP8563E Query Amplitude to read only amplitude.

I want now to improve it in order to read amplitude of the signal each 1/3 Wave-lenght (900MHz). Then I want to save these amplitude in Excel file.

I couldn't connect Amplitude Output of HP8563E Query Amplitude VI to the input of this VI "write in file ".

Could you please tell me how can I Do that.

Regards,

[digital]

Hi,

Before I ask my question I prefer explain you what I am going to do exactely.

I want to make measurement of radio coverage along road by using my vehicle. The sweep time of 8563e is 50ms. So with this sweep time I can only make 1 point measurement each 50 ms. The signal of interest frequency is 900 Mhz (11.8 inch). According to Shannon theorem I want to read 1 point each 4 inch.

So, according to my sweep time 1 point each 50ms this equivalent to 20 points each 1 second.

So, 20 points* 4 inch = 80inch each 1 second.

So,the speed of my vehicle must be not more than 80 inch/s.

So, to do this work I think I have just to improve the Query Amplitude.vi. Because I Need just to read 20 points of peak amplitude each 1 second. Unfortunately I c
ouldn't do that work because when I run Query Amplitude.vi the peak amplitude output in labview and in the spectrum analyzer take more time to change to a new amplitude value provided bu my signal generator.

My question is :

Ho can I do using just the Query Amplitude.vi to read peak amplitude as fast as possible ( for example 20 point each 1 second).

Thank you in advance for you help.

[Rob Cole]

If the frequency that you want is always the same. Set the marker at that frequency (Use VISA send to send MKF 900MHz to set to 900 MHz) then everytime that you want the amplitude, just ask for marker amplitude (Use VISA send to send MKA? then use VISA read to get value). This is the fastest way to get values back. The only traffic on the GPIB is the request and the value. Our HP Spec A. is busy or I would try it to see how fast I can get the data.

I hope that this helps. You may have to setup a timing delay in LabVIEW to read 20 times a second. It may be possible that without the delay, you would be reading more than 20 times per second (take the same reading more than once).

Have fun.

Rob

[digital]

Hi Rob,

I am using a same frequency 900 MhZ.

I have attached a VI that I am using to read amplitude and set frequency.


When I run in continuity query amplitude.vi and I change amplitude from signal generator, the analyzer spectrum and Labview takes more time to display a new value.

So I did't understand why they take time to dispaly a new amplitude.

Could you please tell me why and If you have time send me the application that allows me to do what I said to you in my last email.

Thank you very much for oyur help.
Regards,

[Rob Cole]

According to the HP8560E programming manual, the analyzer can not multitask, so it is either taking a sweep or talking on the GPIB, but not both at once. If you ask it for a measurement, it will wait until the current sweep is complete and then send the data. It will only perform another sweep after the data is sent.

I have included a small VI that assumes that the S.A. is already setup with the frequency of interest as the centre frequency. This VI will move the marker to the centre and then query for the amplitude at the marker as fast as it can. This is the VI that I was going to use to test how fast I could get data from the S.A. (if the S.A. wasn't out in the field).

Give this a try and see how fast it acquires
data. If your maximum sweep rate is 20 per second, once the GPIB communication is thrown in, the rate will drop and I wouldn't be surprised if you got less than 10 per second.

Have fun with it.

Rob

[digital]

Hi Rob,

I've got 6 per second.

I have another question about query amplitude.vi that I've sent to you in my last email.

I would like to build a file in order to put Amplitude output in that file. I tried to use fonction/I/O>> but I couldn't connect amplitude output to "write in file VI".

How can I connect amplitude output to write in file VI.

Please send me query amplitude.vi which can write amplitude output in file.

Thank you for helping me.

Regards,