Looking for a sampling oscilloscope

[dlabanowski]

Hey everyone,

Sorry if a good answer to this has already been posted somewhere, but I can't seem to find it using the search. I have an application where I have some relatively high frequency (1.5-2.5 GHz) signals with a very small (<1 MHz) bandwidth. In this system there are multiple legs which need to have a precisely matched phase and amplitude (basically it's set up as an RF interferometer). I am able to pull out the summed signal, and was hoping to use the readout from a sampling oscilloscope as a guide as I tune each leg to match. Amplitude and frequency accuracy don't have to be perfect as all I'm really doing is adjusting the two signals to line up with each other.

I'm thinking this is an ideal application for a sampling scope which might be able to save me some money compared to a storage scope, but I'd be grateful for any suggestions you may have on what might be best for me to pick up!

Thanks!

[ADT123]

Most sampling scopes on the market today have higher bandwidths than the 2.5 GHz you mention so you may end up with a choice between a 2 or 3GHz real time scope and a 20GHz sampling scope at about the same price. 

If you needed 5GHz or more then the sampling scope argument is stronger - you fall into a middle ground unless perhaps you look second hand or rent?

Pico offers sampling scopes from 5GHz to 25GHz - https://www.picotech.com/oscilloscope/picoscope-9000-series  (see disclaimer below - I am biased!)

Keysight, Tek & Lecroy all either do or have recently offered sampling scopes as well.

[Mechatrommer]

good answer needs good question... your budget?

[MrW0lf]

https://us-shop.ichaus.com/ProductDetails.asp?ProductCode=iC227_Dual_11GHz-_Oscilloscope
iC227 Dual 11 GHz Sampling Oscilloscope
Price: $3,472.75

http://www.fastsampling.com/
Dual Channel 11 GHz Sequential Sampling PC USB Oscilloscope.
Price: $999.00

[dlabanowski]

Thanks for the quick replies! My budget is $5000, but if I can get it cheaper that's all the better! I saw the fastsampling scopes - do they work well / are they still in business? The website looked somewhat derelict.

[nctnico]

How about using a spectrum analyser in zero span mode if the signals have a small bandwidth? Some spectrum analysers (like the Advantest R3477) allow to view the signal in zero span mode giving you an oscilloscope view of the downconverted signal.

[Mechatrommer]

Thanks for the quick replies! My budget is $5000, but if I can get it cheaper that's all the better! I saw the fastsampling scopes - do they work well / are they still in business? The website looked somewhat derelict.

thats a hefty budget. your BW is mere 2.5GHz, cant you consider a used real time DSO? 5 - 6GHz RT DSO is well within your reach, why consider sampling scope that only has 1 application when RT DSO can probably give you 100 other applications for future projects? not including its main usage for analyzing non-repetitive signals? for example this $2.5K 5GHz Lecroy DSO (while its still in my Signature ) and also you can find in ebay few Lecroy's 3 - 6GHz scope for $3 - 6K. at $2.5K, you'll have more room to buy specialized higher impedance probe for the scope, a 3 - 6GHz differential probe for example fwiw ymmv.