SatSig topic:

General Spectrum Analyser question

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Jul 1^st, 2013 at 8:53am

I've never owned a spectrum analyser but I've installed C & Ku band earth stations using a handheld Anritsu which went to 3GHz. What would be a good (say reburbished priced - starting off model) Spectrum Analyser to start with? There's a lot of different types, I sort of know what I want but I'm no expert. I will be doing any type of satellite work I can get. Any feedback would be great.

Jul 1^st, 2013 at 6:01pm

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Hi,
Please share with us what do you expect from the spectrum?
Some guiding questions:
1. Are you looking for L-band spectrum analyzers that can provide DC to the LNB or not? If not, you can get SA with better performance in terms of RBW, VBW and sweep.
2. Are you looking for hand-held, portable or fix SA?
3. Frequency range - L band will be good enough or C band or beyond...?

Jul 1^st, 2013 at 7:23pm

Your experience so far will be a good guide as to what facilities you need.

Think about:

Portability: Weight. Can you carry it up vertical ladders. Handle good for a rope ? Protective carry/flight case. Rain, ice, dust, sand, dropping things on it, including the tea.
All applications: Is a DC block on the input incorporated ? If not, buy one.
Frequency range: DC to 3 GHz is good for 70 and 140 MHz IF tests as well as L band. For some situations you need to monitor the BUC or HPA output spectrum for spurious transmissions and intermod products. You need a very high loss, calibrated, cross-waveguide coupler and an analyser that goes up to the respective RF frequency or a loop test translator.
G/T tests: Useful to have Marker Noise function to display noise power density.
Subreflector alignment: Long single sweep time (~60 sec), trace print or plot.
Sidelobe tests: Need for narrow filter (say 1 kHz), high frequency stability, long single sweep time (~60 sec), trace print or plot.
Illumination: Can you see the buttons to press in the dark ? Is the screen visible in sunlight ?
Interfaces: HPIB/IEE488, plotter, Ethernet, printer.
Your experience: It takes time to learn how to use and once you get good with say Agilent or Anritsu then there is good reason to stick with that type.
Consider renting a spectrum analyser and power meter if doing a contract for a big dish.

If considering buying:
Try eBay and search for spectrum analyser. That will give you an idea of what is available second hand.
Look also at https://www.newerasystems.net/nes-stock-category.html

I hope other will make observations and suggestions also.

Best regards, Eric.