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The precision 10 MHz option is handy if you don’t have access to a GPS-disciplined 10 MHz. As long as your external 10 MHz is clean, an external reference will generally perform about as well as an internal reference, and will perform much better for close-in phase noise (think 10 Hz offset). If your 10 MHz input is not clean, it may actually degrade your system performance.
I should mention as well that for the SA124 broadband channel power measurements, you would need the signal to have a 100% duty cycle.
Our new software release (Feb 2015) will enable the SA124B to make occupied bandwidth, channel power, adj. CP, harmonic distortion, as long as all signals analyzed fit within 40 MHz, and are roughly “white” when viewed as narrow-band. Our current software supports everything but occupied bandwidth.
You can easily measure devices with any bandwidth using the TG and SA. However, these would generally be swept scalar measurements (no vector information for impedance matching). We have single-frequency vector capabilities with our Smith Chart utility, but it does not have all of the VNA length correction features, etc, so you might need a calculator and a few complex multiplies to get a useful vector impedance measurement.
The current TG software is really touchy. It sounds like you are trying to make sensitive measurements. Before you enter TG mode, try setting your reference level to -30 dBm, then attenuator to 0 dB. Then enter TG mode, set reference level to 0 dB, store thru. This should keep the 0 dB attenuator setting and give you a flat response.
The new software will be so much better for this.
We are planning on adding tracking generator compatibility with the BB60C, but we have not established a timeline yet. The down side is that the speed would be limited to 300-700 points per second, about the same as the SA-series. I’ll post more information as it becomes available.
You’d need an ESD-safe work area with hot air. Be sure to get an SMA end-launch connector with the longer barrel. The internal shield will have to be removed–it is soldered down with low temperature tin-bismuth solder. And, of course, it will void any warranty you may have. If you’d like, you can send it to us for a quote instead.
I’ll look into what it would take to add sweeping for these devices. Would a 50-100 point sweep be sufficient? Would a minimum bandwidth of 150 Hz be OK? Would a minimum span of 1 kHz and maximum span of 100 kHz (or 200 kHz) work? Would a dynamic range of 80-90 dB be enough? With 80-90 dB of dynamic range (vs 100+ dB) I think I could display the updated points in real-time so you wouldn’t have to wait for the complete trace…
Andy,
We are moving to the “fast, high dynamic range” sweeps. This should work well for any filter with at least 10 kHz of bandwidth, group delay of less than 100 microseconds, and a starting frequency of > 10 kHz. It will give you about 90 dB of useable dynamic range. Do you have filters that fall outside these specs? If so, we are planning on including an enhanced TG CW utility that allows you to, for example, tune to a single frequency and adjust for maximum insertion loss. You should be able to measure well below 100 dB insertion loss this way, and manually step across your frequency of interest. Similarly, for filters with less than 10 kHz bandwidth, you can manually step across them in increments as small as 10 Hz.