Using NanoVNA SAVER, I calibrate and Sweep using 144Mhz Start 148Mhz end.. and you can set sweep x4.. that's 101 points per MHZ.. It takes a but longer.. The display does look real pretty and if you dump it to printer.. Great..... Now if you are making a filter and using a trimmer cap, each full screen scan takes about 3-4 seconds.. So rotate the trimmer SLOWLY..
There is an advantage to attach an external computer. I don't know the limits, but you can scan more than 101 points. There is a multiplier that divides the span, but increases the points recorded at a decrease in time. A times101 points I've gone to 5.. 5 times as many points 505, and 5 times as long for1 scan. I do not know it's limit.. I'd bet as long as the Start STOP Bandwidth versus synthesizer step isn't exceeded your fine.
Larry Macionski