Forum Replies Created
- Justin Crooks March 29, 2023 at 9:18 am in reply to: Understanding differences between BB60C and D
It is a hardware preselector (band pass filter before any amplification or mixing). There are 12 bands but only 10 of those are true preselector bands. DC-30 MHz is direct to ADC, and 30-130 MHz is a push-pull amplifier.Justin Crooks March 24, 2023 at 10:46 am in reply to: New to SA
The DC block will only affect signals below 100 kHz. Remember when you connect an antenna to use ESD precautions (i.e. ground yourself to the case before and during any antenna adjustments)Justin Crooks March 23, 2023 at 10:40 am in reply to: New to SA
Our accessory kit includes a 20 dB pad, which is enough to make measurements up to 1 watt (+30 dBm). As long as you attenuate enough to keep your signal below +10 dBm, and set your reference level to +10 dBm, and your attenuator is rated for the input power, you should be fine.Justin Crooks March 1, 2023 at 9:37 am in reply to: TG44A Problems
I’m glad you found a workaround. The TG44 is occasionally a challenge to connect the first time, but the Spike software tends to connect easier on subsequent cycles. Hopefully this is your experience as well.Justin Crooks March 1, 2023 at 9:35 am in reply to: SA44B self test fail
If you double check your cables and connectors, and everything looks good, I would recommend requesting an RMA from service (at) signalhound.com. We can take a look at it and let you know what we find.Justin Crooks February 9, 2023 at 10:18 am in reply to: SM4335B
Pulses can be measured using markers in “zero span” mode. Resolution is about 5 nanoseconds.
FM linear chirp / triangular FM can also be viewed and measured using markers in zero span, up to 160 MHz bandwidth
Frequency hopping and pulsed radar: either real-time mode or zero span, depending on the metrics you need.
Barker code: We have wifi tools but no radar tools.
Comprehensive result table: no.
For radar-specific analysis, our hardware plus Sceptre software from 3 dB Labs is a go-to for a lot of people.Justin Crooks January 13, 2023 at 4:55 pm in reply to: Missing SH Port Used in Device Manager
When everything is installed correctly, the SA44B should use the FTDI D2xx driver, not the FTDI virtual com port. It should show up under USB devices, but not under your list of COM ports. Hopefully this helps.Justin Crooks January 5, 2023 at 10:03 am in reply to: GPS signal measurement
I would recommend an active GPS antenna. As long as it has >20 dB of gain, you probably won’t benefit much from an additional amplifier. But these will be low level signals, and might be difficult to measure directly. More accurate measurements could be made by capturing I/Q and processing it using GPS algorithms.
Justin Crooks January 5, 2023 at 9:47 am in reply to: VSG25A output amplitude
- This reply was modified 5 months ago by Justin Crooks.
Into a 50 ohm load, +10 dBm is about 1 V(peak), or 2Vpp. You would probably want a 1-2 watt amplifier with >20 dB of gain if you need 10 V(peak). You would probably also want to filter out harmonics before and maybe after amplifying to make it a good sinusoid.Justin Crooks December 20, 2022 at 4:59 pm in reply to: indicator for Reference Level Offset
Thank you for your recommendation. We’ll add this to our customer feature request list!Justin Crooks November 3, 2022 at 12:56 pm in reply to: Understanding differences between BB60C and D
We also added a preselector to the BB60D. It is a sub-octave preselector designed to greatly reduce any second-order nonlinearities (IP2) above 130 MHz by rejecting out-of-band energy.
Below 130 MHz, we have a direct conversion band to 30 MHz, and above that a band that uses a push-pull amplifier to improve IP2 (but to a lesser extent than the preselector).Justin Crooks November 3, 2022 at 12:45 pm in reply to: Understanding differences between BB60C and D
The BB60D uses the same ADC as the BB60C. It’s a very good 14 bit ADC. The dynamic range improvements came from using high IP3 amplifiers and mixers, and carefully balancing gain through the entire signal chain (too much or too little gain anywhere in the signal chain and either your noise floor or linearity pay a price).
Distortion free dynamic range is 2/3 (IP3-DANL). With a -10 dBm reference level, IP3 at 1 GHz (on the most recent unit calibrated) is +15 dBm, and DANL at the same settings is -142 dBm for a 1 Hz bandwidth, so dynamic range would be about 104.7 dB at 1 GHz, normalized to a 1 Hz RBW. It would be lower at 6 GHz than 1 GHz, and obviously lower at higher RBWs as well.
We do not spec dynamic range, but we do specify worst case DANL and IP3. Hopefully this helps.Justin Crooks August 10, 2022 at 9:49 am in reply to: Chirp Modulation Signal generation
Both devices have an Arb mode, but the VSG25 is limited to 2k symbols (very small buffer). It looks like these chirps are often clustered together in a sequence, and never wider than about a MHz, so the VSG60A would be the right choice, since its buffer is on the PC/laptop and can be very large if needed.Justin Crooks April 20, 2022 at 4:54 pm in reply to: VSG60 reference
Glad you found it. +/- 1 ppm initial, +/- 1 ppm/year. A typical unit will be quite a bit tighter than this.Justin Crooks April 14, 2022 at 10:21 am in reply to: Extended Power Range?
Unfortunately we have several switching regulators in our power supply that have a maximum operating input voltage of 16 volts. We could have added an additional DC-DC conversion in front to extend this, but this would have reduced efficiency and added heat for all customers.
There are quite a few 24V – 12V DC-DC converters on the market. I realize it’s not an ideal solution, but hopefully it will work for you.Justin Crooks January 24, 2022 at 10:26 am in reply to: load a saved trace
You should be able to export your good trace, offset by some amount (e.g. 2 dB) in spreadsheet software, and then import it as a limit line. This might be another approach to consider.Justin Crooks January 14, 2022 at 9:53 am in reply to: GPS Signal Generation
I know Matlab has some tools for GPS signal generation. You could also just use one of our receivers, a bias tee, and a good GPS antenna + preamp to capture a GPS signal and then play it back with the VSG60A.Justin Crooks January 11, 2022 at 4:24 pm in reply to: smSyncErr errors suddenly with SM200C
Thank you for bringing this to our attention. I will alert our software team to this issue, and see if they can duplicate it.Justin Crooks January 11, 2022 at 9:54 am in reply to: SM200C noise at lower frequencies
You will notice in the specifications that the DANL (noise floor) specification is 4 dB higher below 700 MHz vs. above 700 MHz. A 4-5 dB step in the noise floor is normal. This is due to a design decision to optimize for noise figure in the 700 MHz – 2700 MHz communications band, and to push for better linearity at low frequencies.Justin Crooks January 10, 2022 at 10:28 am in reply to: SM200C noise at lower frequencies
I’m not sure what signal you’re looking at there, but it is possible that level of noise is actually on your signal. You can turn the preselector on and off below 640 MHz, and change your reference level by 10 dB. If the noise level changes considerably, it may be partially from intermodulation inside the SM200C. Otherwise, it is likely part of your input signal.