Hi,
I try to help a fellow radioamateur to get a HP8596E to work. First look at the analyser show that the levels are shown much to low. (The CAL-output is ok and checked with another instrument.) When the attenuator is set at 40dB the signals dissapear indicating that the attenuator might be blown.
Has anybody seen any similar before?
What I feel strange is that if I select "Analog+" the levels are displayed right - of course not when the 40dB attenuator is engaged. Could this indicate that the input mixer is ok and that it's "only" the attenuator that is damaged?
(When the analyzer is started with the CAL connected to the input it shows levels 40-50dB below what it should show.)
Any hints would be apreciated. Any information about CLIPs would of course be of dramatic help compared to where I am right now without any schematics.
Is there any way of reset the instrument to be as it was when delivered from the factory? It seems as there are many things stored in the instrument and I just wanted to be sure that none would interfear with the readout.
Regards
Jens
I try to help a fellow radioamateur to get a HP8596E to work. First look at the analyser show that the levels are shown much to low. (The CAL-output is ok and checked with another instrument.) When the attenuator is set at 40dB the signals dissapear indicating that the attenuator might be blown.
Has anybody seen any similar before?
What I feel strange is that if I select "Analog+" the levels are displayed right - of course not when the 40dB attenuator is engaged. Could this indicate that the input mixer is ok and that it's "only" the attenuator that is damaged?
(When the analyzer is started with the CAL connected to the input it shows levels 40-50dB below what it should show.)
Any hints would be apreciated. Any information about CLIPs would of course be of dramatic help compared to where I am right now without any schematics.
Is there any way of reset the instrument to be as it was when delivered from the factory? It seems as there are many things stored in the instrument and I just wanted to be sure that none would interfear with the readout.
Regards
Jens
You can easily test the integrity of the input attenuator but you will need another functioning spectrum analyzer; perhaps a power meter would work also, but a power meter measures broadband, so any harmonics of your input signals will be measured by the power meter. If you inject a signal of known amplitude into the RF input, you can then disconnect the semi rigid cable on the output. Let’s say that you injected a signal at 50 MHz at -10 dBm. If the input attenuator is set to 0 dB, the output of the attenuator should measure -10 dBm. As you increase the attenuator in 10 dB steps, you should see the output power decrease by 10 dB as well. Since you are measuring raw hardware performance, there are no digital or video corrections to be concerned with. With 40 dB of input attenuation, the functioning spectrum analyzer should measure -50 dBm (-10 dBm – 40 dB) at 50 MHz. If you see any jumping around or signals disappearing on the spectrum analyzer display as you change attenuation settings, then one or many of the attenuator sections are blown or defective.
The input attenuator itself is no longer available, but it appears the internal circuits are: The 10 dB section is part number 1GT1-3737, the 20 dB circuit is part number 5086-2380 and the 40 dB circuit is part number 5086-2381. Contact www.agilent.com/find/parts to order.
Regards -