Power measurements and testing Voltmeter DVM ---R&S RTM3K Oscilloscope Road-Test Review

RE: Power measurements and testing Voltmeter DVM ---R&S RTM3K Oscilloscope Road-Test Review

geralds — Tue, 19 Feb 2019 20:46:25 GMT

Hi,

Fantastic! This is one of the best review I've seen.

I've bookmarked all your parts of your review.

Thanks

Best Regards

Gerald

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RE: Power measurements and testing Voltmeter DVM ---R&S RTM3K Oscilloscope Road-Test Review

DAB — Mon, 30 Jul 2018 19:17:35 GMT

I remember having to do all of those measurements by hand.

These new scopes are very powerful.

DAB

RE: Power measurements and testing Voltmeter DVM ---R&S RTM3K Oscilloscope Road-Test Review

jc2048 — Mon, 30 Jul 2018 10:47:40 GMT

The tools that the oscilloscope provides look really useful for doing these measurements. Thank you for showing us this in addition to your main review.

A couple of questions for you.

I don't know much about spectrum analysers (never having used one), but don't you need to set a RBW of much lower than 4MHz to pick out a 4MHz fundamental and its harmonics sensibly? The RBW defines the resolution, doesn't it?

With the transient test, what was the transient that you were measuring? Did you have a switched load on the output? The results look much too good to me (although a 4MHz converter is going to be fast, you wouldn't expect the control loop to recover things that quickly - a rough 'rule of thumb' is that the control loop bandwidth might be something like a tenth to a twentieth of the switching frequency). Or were you just showing us how the measurement might work by simply letting it measure the rise time of the ripple?

BTW It might not be a good idea to run your analogue PSU with a rug blocking the ventilation for the power transistor heatsink inside. Won't matter for the situation in the picture, where it's only supplying 20mA, but it might matter at higher output currents. You might know to remove it under those circumstances, but it sets a bad example to others who don't.

RE: Power measurements and testing Voltmeter DVM ---R&S RTM3K Oscilloscope Road-Test Review

rachaelp — Mon, 30 Jul 2018 10:28:18 GMT

I've got a similar option in my Keysight MSO-X3054A but unfortunately I can't use it as it requires a Keysight specific AC/DC current probe which costs thousands of pounds in order to work :-( I assume there is no such requirement for this or did you have access to an AC/DC current probe which worked with your scope?

RE: Power measurements and testing Voltmeter DVM ---R&S RTM3K Oscilloscope Road-Test Review

three-phase — Sun, 29 Jul 2018 19:44:42 GMT

Another good blog, seems like quite a useful feature to have.

Kind regards

RE: Power measurements and testing Voltmeter DVM ---R&S RTM3K Oscilloscope Road-Test Review

snidhi — Sat, 28 Jul 2018 15:37:19 GMT

Thank you Gene [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-09af92f9-4349-4431-aa1c-8d79a71272fb/contentimage_5F00_1.png:16:16]

RE: Power measurements and testing Voltmeter DVM ---R&S RTM3K Oscilloscope Road-Test Review

genebren — Sat, 28 Jul 2018 15:26:31 GMT

Another great addition to your roadtest review. The layers of detail that you have generated in this review are quite impressive. All of these features are making less and less satisfied with my present oscilloscope.

Gene