FG-100 Review

Thread Starter

Wendy

Joined Mar 24, 2008
22,647
This May I bought this function generator. This is my review. Overall I was very impressed. $30 American I thought it was a fairly good deal. It does clip badly with the level turned all the way up.Frequency stability was excellent, I do miss the ability to sweep through a frequency on both sides. For a pure waveform it is more than adequate.

FG-100.jpg
Please bear with me while I acquire images of all the modes. I will post them as I get them.
Bad news first:
Loads are 75Ω
I will start off using extreme settings, 500KHz maximum level.
500 KHz.png 500 KHz 75 ohm.png 500 KHz 75 ohm clipping.png 500 KHz 75 ohm adj.png
...................1........................................2..........................................3.........................................4

1.No Load. Looks pretty good.
2 Loaded, maximum output, pretty ugly.
3. Loaded,Output adjusted to just before it stopped clipping.
4. Loaded,Output adjusted to maximum value having a clean output. Looks pretty clean.

Now for the fun part, from here on I will keep the level adjusted to put out a clean waveform. So the level shown will be assumed that will be the maximum output that this device can give. It is understood that it can offset DC to wherever you need it (to create digital pulses for example). I use a five Volt power supply using a USB cube I have at my workstation, this does limit the output somewhat. If you need more amplitude, you are just going to have to build your own amplifier.

As it happened, none of the other waveform functions worked 500KHz, everything came out as a sine wave. So I dropped the frequency down to 100KHz and tried it again.

100KHz

1a.png 2a.png 3b.png 4b.png 5b.png
..................1.........................................2.......................................3...........................................4.......................................5
1. Sine wave.
2. square wave.
3. Triangle wave.
4. Sawtooth
5. Ramp.
6. Reverse ramp.

<continued on next post>​
 
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Thread Starter

Wendy

Joined Mar 24, 2008
22,647
Now we will try 1KHz:

1b.png 2b.png 3b.png 4b.png 5b.png 6b.png
................1...........................................2.........................................3.........................................4......................................5.........................................6
1. Sine wave.
2. square wave.
3. Triangle wave.
4. Sawtooth
5. Ramp.
6. Reverse ramp.
7. Close up view of the triangle wave. I thought it was interesting because it shows the digital steps.

Overall I would rate this device a good value for your money. I was very impressed by the frequency accuracy as shown by the scope displays. It is not perfect, but I have been trying to be impartial in showing what it does. I hope you have enjoyed this review.

I will address the output adjustment issue in my next Completed Project submission.

Wendy Marsden
 
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DickCappels

Joined Aug 21, 2008
8,000
It looks like a nice, clean little package.

How are the settability and jitter?

What is the range of P-P output and offset?

My analog function generator developed dirty pots over the years and is now unusable and I don't really care to replace all those pots, so DDS synthesizers are attractive.
 
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