Bottlehead Forum
General Category => Technical topics => Topic started by: 4krow on April 05, 2016, 01:59:19 PM
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Let me start over. In another thread, I asked what equipment that I might need to accomplish measurement of filters that I work with. After buying the recommended equipment (or at least some of it), I found that it would require graphing out responses on paper. While I wouldn't mind doing this, I can promise that it is an opportunity for me to make even more errors than I usually do. I almost bought a third piece of equipment, i.e. a sweep frequency generator, but then stopped short until I get a better idea of the right equipment needed. First of all, I have purchased an Oscilliscope, and a benchtop DMM capable of signal generating. That's fine. These are great pieces that I have ended up with, and will keep, but I need to complete the set in order to measure the effect of these notch filters that I work on (among other filters). Soooo, what is the recipe? Thanks in advance.
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The easiest way to do this stuff these days is usually with a sound card, a laptop and the right piece of measurement software. I haven't been keeping up with the latest, but there are usually inexpensive and even free software packages out there tailored to making frequency response measurements.
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Thanks Doc. Actually, I was afraid that this might be the reply. Thing is, I still like the old stuff...go figure, but you know, it wouldn't be that big of a deal I guess to go with the flow.
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Well, as far as old school goes I used to one of these and it was very nice.
http://www.ebay.com/itm/HP-35665A-2-Channel-DC-to-102-4KHz-Dynamic-Signal-Analyzer-with-manuals-/152012654982?hash=item2364a90986:g:fcEAAOSwoBtW47zU (http://www.ebay.com/itm/HP-35665A-2-Channel-DC-to-102-4KHz-Dynamic-Signal-Analyzer-with-manuals-/152012654982?hash=item2364a90986:g:fcEAAOSwoBtW47zU)
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Thanks Doc,
That's Exactly what I am trying to describe. This one is out of my budget now since I spent the money on the other two pieces of equipment, but at least now I know specifically what to look for.
Greg
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You can pick up an inexpensive signal generator. With your scope on the output, a lot can be gleaned by just turning the frequency knob back and forth and observing the trace. Once you get close to what you are looking for, you can drag out the graph paper...John
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ohn,
I appreciate the input. There is a lot of these things for sale out there, but I mean to get a bit more specific before I just buy one. What I mean one like you are describing would most likely have a dial to adjust the frequency, which is what I am looking for. The Keithley that I own can adjust frequency, but each freq is like a new setup, making the simple, unsimple :o
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Yea, something like this. I'm sure there are a zillion used ones out there...John
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A $40 sound card, a 10-year-old PC, and a free piece of software will do exactly what you're looking for, and you won't need a 300 page instruction manual.
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Believe me, even though I have purchased most of the equipment, I am very much thinking about doing just that concerning a simpler way. The money has to come first...it's on 'backorder'