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Six_Shooter
02-13-2013, 06:06 AM
I know there's a few electronics guys here, and I'm looking for a Function Generator to add to my electronics work bench. I have a post in the classifieds forum for that specifically.

For anyone that has experience with function generators, what do you, or have you used, and what do you look for in one?

I have found a Velleman unit locally, that is a portable unit. I would prefer a bench top model, but at $109 this might be a good investment to even use as a portable unit for field diagnostics, I'm just not sure of the quality. I do have a Velleman PC Oscilloscope that seems to work fine, though I haven't used it much, so I'm not really afraid of the unit breaking down, just accuracy. If I get it I plan to take it to school and test it against the Function Generators we have there. http://www.vellemanusa.com/products/view/?id=525983

There is also this Velleman model, that would match my O-scope, but I already have the O-scope as PC required. I'm not sure I want to have both connected to the PC in that sense. http://www.vellemanusa.com/products/view/?id=523616

I'm looking to keep this as cheap as possible right now, since I am in school and need to save up for next year's tuition, and everything else that goes along with school. So give me your ideas.

dave w
02-13-2013, 04:54 PM
My experience using a function generator is mostly from my military service (20+ years ago), radars and aircraft navigation systems. Generally the function generator would create a signal usually sine wave or square wave ranging from a few Hertz to upwards of 10 Giga Hertz. One limiting factor of a function generator is the amplitude and amperage output available. It's not likely an automotive application is going to need 108 Mhz sine wave at 5 watts, something typical to calibrating an aircraft instrument landing system. One practical automotive application for a function generator would be to provide a simulated AC sine wave output from a distributor pickup coil or a simulated square wave output from an ignition module. Changing the frequency output of either simulated the AC sine wave of an automotive pickup coil or simulated square wave from an ignition module will change the simulated RPM read by the ECM / PCM.

dave w

Six_Shooter
02-13-2013, 07:58 PM
I understand the use of a function generator, I use them at school. This work bench is not limited to automotive, it is a general electronics bench, testing, repairing, building, etc.

Just looking for input from people that may have used more brands or models than I have, and what features are used most.

dave w
02-14-2013, 12:47 AM
The one that is used where I work is from Agilent http://www.home.agilent.com/en/pc-2153501/33500b-series-waveform-generators-20-30-mhz?nid=-33134.0.00&cc=US&lc=eng Which can be programmed with the benchlink waveform build pro software. http://www.home.agilent.com/en/pd-1962285-pn-33503A/benchlink-waveform-builder-pro-software?nid=-536902257.977229&cc=US&lc=eng The Agilent equipment is overkill!

Agilent is a spin off company from Hewlett Packard (HP). Many years ago, HP was mostly an electronics test equipment manufacture. The function generators I used during my time in my military were HP products. The most common uses for me were for making waveforms, sine, square, and pulsed DC. I haven't looked for used HP funciton generators, but I'm sure there are decent deals to be found on the older HP function generators. I'm sure similar decent deals can be found if looking for a used Textronix function generators.

As a guess, San Jose (Silicon Valley) or Portland Oregon (Silicon Forrest) are possible areas in the US to look for decent prices on used electronic test equipment. Intel has several sites in Hillsboro Oregon, just west a few miles from Portland.

dave w

bentrod
02-14-2013, 09:52 PM
removed

Six_Shooter
02-14-2013, 10:00 PM
I would love to save up and get one like my school has (brand is not coming to me right now).

I'm thinking that for now I might pick up that hand held Velleman, to use until I can afford a good one. Basically I want to be able to perform my lab assignments at home, to either get some idea of what I need to do before the actual lab period, or try again, without needing to spend the time at school.