Thanks for the good discussions – it’s very informative and helpful. I appreciate all the posts and hopefully they will help others here read or search in the future for spectrum analyzer advice.
Regarding the budget, this is for an amateur/educational endeavor so the budget is driven by what is feasible/practical and not by an absolute figure ($1k is just a benchmark). The budget could be higher and of course it would be nice to go lower but it isn’t going to provide a financial return on investment (as a professional application would) so this spectrum analyzer goes in the nice/want to have bucket vs. the need to have bucket. - So maybe we could set the price aside for a while and look at possible specs and features. Plus, others might have a different budget so I’m inclined not to rule out anything on price just yet – at least until I can better understand the price/performance tradeoffs. Having said that, in my case it’s hard to imagine spending over $2k and at that I would have to have my head examined.
Regarding bandwidth, 1.8 GHz is not an absolute, it could be 1.5 GHz or elsewhere in the 1-2 GHz range. However, if it were possible to get to 2.5 GHz that would reach the Wifi range and if BW could get to 5 GHz that would be even better for Wifi. (Although perhaps with harmonics even more BW is needed?) Obviously, as the bandwidth goes up so does the price – but let’s set the price aside for the time being.
Regarding RBW, it would be good to get smaller increments than 9 kHz. Getting to below 100 Hz would be great to cover audio. On the other hand, if the price uplift (I know I said we were going to set that aside) is too great to cover audio then maybe a separate solution (PC sound card?) might make sense for audio. I had a sense for these tradeoffs before my original post but all the discussions have now surfaced these tradeoffs and more with better clarity.
Regarding possible equipment it seems there isn’t a lot confidence in some of the vintage models. The Tek 49x series looks cool but it doesn’t get a lot of love here. Likewise for the Tek 27xx series? Perhaps as avvidclif said "Tek make's scopes, HP makes everything else". I’m not ready to rain on Tektronix’s parade (I love their analog scopes) but I get the idea that not everything has to be Tek.
The HP units seem to come in at least 3 possible series: 856x, 859xE, and 859xL.
There is also Wuerstchenhund’s Agilent E7595A/B which looks very interesting; I’m inclined to set it aside for a moment and declare it a finalist that can be compared against one or a few other finalists. I’m also inclined to put the Rigol DSA815-TG in the final consideration bucket too. Let's put Rupunzell's HP 141T on the finals table too - it looks gorgeous in a vintage kind of way.
So the question is what other used equipment might outperform these two models on value (ie, price, functionality, and performance; reliability will also ultimately become an important consideration to be made – but for now let’s assume that a good working condition used unit can be found if someone searches hard enough).
In the 859xL series are some contenders:
8590L 9 kHz – 1.8 GHz
8594L 9 kHz – 2.9 GHz dc coupled (100 kHz – 2.9 Ghz ac coupled) - probably going to stress the budget
According to the HP specs both offer RBW of 1 kHz to 3 MHz in a 1,3,10 sequence.
In the 859xE series are some contenders:
8591E 9 kHz - 1.8 GHz
8594E 9 kHz - 2.9 GHz
8595E 9 kHz - 6.5 GHz
According to the HP specs all three offer RBW of 30 Hz to 3 MHz with 10 Hz Nominal.
In the 856X series are contenders:
8560A 50 Hz – 2.9 GHz - probably going to stress the budget
8561B 50 Hz – 6.5 GHz - probably going to break the bank
According to the HP specs both offer RBW of 10 Hz to 1 MHz in a 1,3,10 sequence and 2 MHz.
Any thoughts on the tradeoffs among the above models? (The 8591E, 4E, and 5E look like very good price performers.)
Beyond frequency range and RBW are a bunch of other specs and considerations. Phase and SFDR measurement performance seem to be worthy considerations. Any other considerations on buying criteria and potential models are very welcome.
Thanks, EF
PS, I'm kind of in the same boat with what nixfu says in his post above - I'm betting there are others in this boat too so the wisdom from the experienced users is definitely appreciated.