EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: asadullah mir on March 04, 2017, 02:16:18 pm
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EDIT: Deleted a duplicate
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I own both a B&K 4017 and a B&K 2017. I highly recommend giving them the miss.
Reasons;
1. Very poor waveform above about half the rated max freq.
This is a common problem with most function generators. DDS function generators get around it by limiting the maximum frequency of most of their waveforms so they are no better and usually worse.
2. B&K have kept service information under wraps. No schematics available and B&K refuse to issue one, upon request. Repair is a bitch and I would rather give them away than attempt a repair.
I agree but would apply this to any recent function generator; service documentation was discontinued around 1990 although B&K did not have it even before then. At the same time though, I would not recommend buying an older function generator which has service documentation unless you are prepared to maintain it.
I have one of the older B&K function generators and a Beckman Industrial one and it looks to me like they were all ultimately designed or manufactured by the same company. Even the Tektronix CFG ones seem to be identical. It is not a bad design but the old HP and Tektronix FG models are better.
3. They do have frequency meters built in but at fixed 0.1Sec 1 Sec and 10 Sec gate time, the resolution accuracy and speed are abysmal.
4. They drift like a rudderless ship at sea. Freq stability is next to none.
Considering the stability, the resolution of the frequency counter is adequate. Some designs are better than others but if you want higher stability and lower jitter, then a synthesized or DDS design is required. Considering that active circuits are usually no better than 1%, even a calibrated dial without a frequency counter is good enough.
I suggest you look at something like say a S3200s they can be had for as little as 50US$ and the performance is miles above B&K. Take a look at some YT videos and you will know more.
I will give away my two B&K free if someone will pay for the freight charges.
I live in Pakistan so it might be that the SY3200 will cost less to get.
I now like the old Tektronix function generators but HP has some old nice ones also. One way to get better waveform accuracy at higher frequencies is simply to get a higher frequency generator.
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I just bought a non working B&K 3020. I was easily able to find an instruction manuel, schematic and even suggestions on how to use it. I suspect it will be easily repairable. Looking inside it may not be up to HP standards but that probabily is a good thing, since it appears to have no propriatary chips, no markings were scraped off to hide the identities.
It only costs 25usd shipping included.
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I just bought a non working B&K 3020. I was easily able to find an instruction manual, schematic and even suggestions on how to use it. I suspect it will be easily repairable. Looking inside it may not be up to HP standards but that probability is a good thing, since it appears to have no proprietary chips, no markings were scraped off to hide the identities.
It only costs 25usd shipping included.
Where can I get one of these? Was this the only one or one of several on sale?
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This is a common problem with most function generators. DDS function generators get around it by limiting the maximum frequency of most of their waveforms so they are no better and usually worse.
That would not be a problem. The produce what they claim
I agree but would apply this to any recent function generator; service documentation was discontinued around 1990 although B&K did not have it even before then. At the same time though, I would not recommend buying an older function generator which has service documentation unless you are prepared to maintain it.
Yes! that is generally true but from what I have seen of the new crop of sig gens from china, since they are based heavily upon standard ICs of which the data is available they present a much smaller problem fixing.In fact they can be easily improved ( ground runs, bypassing, filter redesign etc)
I now like the old Tektronix function generators but HP has some old nice ones also. One way to get better waveform accuracy at higher frequencies is simply to get a higher frequency generator.
Absolutely. I have an HP 8116A and I love that one + will buy another when ever a good bargain shows up. ( Yes I am one of theme silly collectors)
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This is a common problem with most function generators. DDS function generators get around it by limiting the maximum frequency of most of their waveforms so they are no better and usually worse.
That would not be a problem. The produce what they claim.
Some are much better than others and even some old style analog function generators change frequency ranges on different waveform settings but that is rare.
My ancient 2 MHz B&K 3022 which shares a very common design has pretty poor triangle and square wave performance at the upper end of its frequency range. But my even older Tektronix 11 MHz FG502 which uses a completely different design not shared by anything modern is much better even at the upper end of its frequency range. The FG502 also has pulse and ramp output selections to go with the standard square, triangle, and sine selections which operate at 1/10th the frequency which is like what a modern DDS function generator does but that is rare on an analog function generator.
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The B&K I got was a one off, listed as non working, which it is. If it can get it to work like its claimed I can start using it for some hearing aid experiments. I will also start giving free hearing screenings at the local schools.