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Idea: Measuring parameters at different drive levels

 

Does any VNA measure and show parameters at different drive levels.
Active circuits saturate and class C amplifiers are not linear at all. Using different levels could give more and better information about the circuit.

Showing cloud of parameters like waterfall display in spectrum analysers, would tell usable range of the circuit (and require 3d display?).
 

My 8510 does, but then it's 100 kg heavier than the Nano.? Kent

On Monday, January 16, 2023 at 08:23:39 PM CST, Leif M <leif.michaelsson@...> wrote:

Does any VNA measure and show parameters at different drive levels.
Active circuits saturate and class C amplifiers are not linear at all. Using different levels could give more and better information about the circuit.

Showing cloud of parameters like waterfall display in spectrum analysers, would tell usable range of the circuit (and require 3d display?).
 

Some high-end commercial units can do measurements at swept power levels, but none of the nanoVNA or its relatives.
Also note that the nanoVNA stimulus is not sinusoidal but is a square wave, so active devices will not act the same as they will with a sine wave stimulus.
In general they are not suitable for characterizing active devices,
73, Don N2VGU
 

Oh. Does NanoVna2 also use squarewave measuring signal? I mainly use V2 Plus4

Yes, any NanoVna would require large HW changes I think. Maybe sometime.
Jim Whartenby
 

DonIt seems that this thread is headed in the direction of Load Pull measurements.? Those interested can get a heads up here:,Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy

-----Original Message-----
From: Donald S Brant Jr <dsbrantjr@...>
To: [email protected]
Sent: Mon, Jan 16, 2023 8:32 pm
Subject: Re: [nanovna-users] Idea: Measuring parameters at different drive levels

Some high-end commercial units can do measurements at swept power levels, but none of the nanoVNA or its relatives.?
Also note that the nanoVNA stimulus is not sinusoidal but is a square wave, so active devices will not act the same as they will with a sine wave stimulus.?
In general they are not suitable for characterizing active devices,
73, Don N2VGU
 

On 1/16/23 6:23 PM, Leif M wrote:
Does any VNA measure and show parameters at different drive levels.
That's the kind of capability you get when you step up to the multi-thousand dollar level.

Active circuits saturate and class C amplifiers are not linear at all. Using different levels could give more and better information about the circuit.
Showing cloud of parameters like waterfall display in spectrum analysers, would tell usable range of the circuit (and require 3d display?).
Yes. and there's all kinds of interesting measurements and analyses possible.

If you look at the Keysight/Agilent/HP PNA analyzer literature, you'll see a lot of this kind of thing



Pulses, various amplitudes, etc.
 

Take out the "Regards,Jim" and you won't get a "404"

On 1/16/2023 10:35 PM, Jim Whartenby via groups.io wrote:
DonIt seems that this thread is headed in the direction of Load Pull measurements.? Those interested can get a heads up here:,Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy

-----Original Message-----
From: Donald S Brant Jr<dsbrantjr@...>
To:[email protected]
Sent: Mon, Jan 16, 2023 8:32 pm
Subject: Re: [nanovna-users] Idea: Measuring parameters at different drive levels

Some high-end commercial units can do measurements at swept power levels, but none of the nanoVNA or its relatives.
Also note that the nanoVNA stimulus is not sinusoidal but is a square wave, so active devices will not act the same as they will with a sine wave stimulus.
In general they are not suitable for characterizing active devices,
73, Don N2VGU

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