| Products > Test Equipment |
| OWON XSA1032-TG 3.2G Spectrum Analyzer |
| << < (5/8) > >> |
| TomC:
--- Quote from: mawyatt on May 10, 2023, 12:47:09 pm ---What you are likely seeing at these lower frequencies is the phase noise of the SA sweeping oscillator which has a 1/f^n characteristic. The better the oscillator 1/f PN the better noise floor in this low frequency region. BTW great buy for the OP, ~$600 :-+ Best, --- End quote --- Thanks for the tip! Looks like you nailed it! I see at least a 10dB difference by just changing the Sweep from Auto (about 29ms in this case) to Manual 500ms. So at least at the very beginning of the sweep that made a big difference. I set the reference level to -30 in this set of attachments for better accuracy. Thanks again! :) |
| TomC:
TG Output at Different Frequencies Part 1 Some of the XSA100 series SAs can use the TG output as an independent CW generator. However, the XSA1032-TG is not one of them. The soft menu selections for this feature are grayed out as can be seen on attachment 2. But as is the case with other TG SAs, it's still possible to set the Span to Zero, turn on the TG output, and use the FREQ soft menu to set the output frequency (see attachment 1). The output level can then be set via the Source soft menu (attachment 2). 0dBm is the highest level and what I'm using for all the screens I captured from my SDS8202 DSO. Attachment 3 is a screen of one of my favorite dB calculator websites showing some conversions for 0dBm. The website is at: https://www.analog.com/en/design-center/interactive-design-tools/dbconvert.html |
| TomC:
TG Output at Different Frequencies Part 2 The bottom left of the OWON SDS8202 screens shows a few automatic measures, but the names may be confusing, Vk is what they use to identify the RMS measurement, and Vp is what they use to identify volts peak to peak (Vpp). One other thing that may be confusing is that on the FFT screens the scale is on dBV, which is not mentioned anyplace as far as I know. The SDS8202 is rated as a 200MHz DSO, but on attachment 14 I think the drop in signal strength is due to the DSO being at the limit of its bandwidth. Note: I had to replace the attachments because they were hard to read. |
| TomC:
9kHz to 100kHz Spectrums and Frequency Response For these tests I'm using an OWON AG1022F Arbitrary Waveform Generator (AWG or ARB). The relevant specs for the Sine output and Sweep function are attached. Attachment 3 shows the AWG setup to output a 25kHz Sine at 633mVpp, since I'm using 50Ω that's around 0dBm. There's just a short 20" cable between the AWG and the SA. Attachments 4-7 show a few spectrums for AWG outputs in this range, including the 25kHz shown in attachment 3. They look pretty clean to me, don't even see any notable harmonics, and the dB levels seem fine. Attachment 8 shows the AWG's setup to output a Sweep from 9kHz to 100kHz. I set the sweep length to 220 seconds to try to capture the frequency response using the SA's Trace Max Hold function. The idea is to let the SA sweep several times before the AWG changes the frequency (SA's sweep is set to auto which in this case is 404ms). Attachment 9 shows the SA's screen halfway thru the process, and attachment 10 shows when the process is completed. The entire process takes about 4 minutes. I don't know if there is an easier way to do this! So any one with a better idea please chime in. :) |
| TomC:
Frequency Response Test To perform this test, I need a signal generator with a range that at least covers 100kHz to 3.2GHz with a nearly flat response. Unfortunately, I don't have a generator that matches those requirements. My AG1022F has an adequate response, but maxes out at 25MHz. I also have the Windfreak SynthUSBII that has a 34MHz to 4.4GHz range but has an uncalibrated output and the response is around plus or minus 4dB. So, I tried to do the test in two sections, 100kHz to 25MHz, and 34MHz to 3.2GHz. The first section gave me what I think are fairly accurate results, but the second section is just showing the response of the generator, not the SA. |
| Navigation |
| Message Index |
| Next page |
| Previous page |