To buy a function generator

Discussion in 'General Electronics Chat' started by TBayBoy, Jun 5, 2011.

  1. TBayBoy

    Thread Starter Member

    May 25, 2011
    Next for consideration is a function generator, I've looked at some kits but am worried that these may be a bit flaky.

    Mostly what I intend to wok on is clock and radio type circuits, maybe some audio, that kind of work.

    What features should I be looking for? What are some of the things I should avoid?

    Thanks in advance for your input.
  2. monster_catfish

    Active Member

    Mar 17, 2011
    You can't go wrong with a B&K Precision unit. Check out Test Equipment Depot for a selection.
  3. someonesdad

    Senior Member

    Jul 7, 2009
    It's mostly driven by what you want to spend. At the low end are the inexpensive analog-type function generators. As you go up in price, you start getting into the DDS generators (direct digital synthesis). At the top end you encounter the arbitrary waveform generators, which provide typical function generator behavior along with the ability to let you define your own waveform and play it back. This latter feature is very useful for custom testing situations. You can go to B&K's download site and get their guide to function generators -- it might have some useful information. Go here to see a variety of generators.

    Another option is to buy a used piece of equipment. This is what I first did and got an older Wavetek 144 sweep generator. It's quite nice and the sweeping ability is occasionally useful -- for example, to characterize a circuit's response as a function of frequency using a scope. You can sometimes find beautiful old lab-quality stuff for pennies on the dollar. I had a friend who bought 10 or 15 HP 3326 dual synthesizers as government surplus and sent me one for free; it works perfectly and is a gorgeous piece of equipment (it's two of the famous 3325 generators in one box).

    If I was starting out, I'd probably buy B&K's 4003 generator, as it has all of the basic features I'd want -- and the 5 digit frequency counter would be nice to have (the low end generators typically have a low-resolution dial to set the frequency).

    If I wanted a DDS generator, I'd spend the extra bucks and get the B&K 4075 arbitrary waveform generator because it would fit my needs the best (I have a 4076 generator on loan and it's a nice generator).

    For the type of stuff I do, it's seldom that I need to go over 1 MHz and quite rare to go over 10 MHz. I find most of the stuff I work with I'm interested in frequencies from 0.01 Hz to around 100 kHz. So it's also worthwhile knowing what kind of stuff you're going to be working on to help you pick a frequency range.
  4. TBayBoy

    Thread Starter Member

    May 25, 2011
    Thank you for your opinions, helpful as always. Currently I am looking at a B&K 3011B or a QUAKKO SFG 2003 DDS. They both seem to fit my needs, so will have to do some more research.