I was just using my waveform generator to trace a circuit when all of a sudden the signal just disappeared gone. I thought maybe I did something wrong but nope I didn't. reset didn't help and other than no output the unit seems to be working as it's supposed to. The only thing I have left is a signal injector I built in my teens. It works but It's a pain in the rear to use. I'll have to look into the one that quit on me and see if I can get it running again. It was not the top of the line either and plans were in the works for a new one but that was up the road a bit. Like I said great week first a blown up fish finder and now no signal generator. Lovely. :-(

 

Well I got it sort of working again. It would seem that the unit blew something as when I generate A sine wave I get a flat spot on every cycle. starts out at 0V and then about 1/2 way through the upper positive going wave it wakes up and completes the rest of that cycle and the process repeats again on the next cycle. So I'll have to look very carefully and see exactly what may be causing the problem. I have a feeling it's a MOSFET or a transistor I'm not sure which one they may have used on the output. It is not that complicated a design and the thing runs on a 5 volt supply. It's not the best and it was due to be replaced in the future I was just figuring out the features I would want in a signal generator.

 

I took the thing apart and I am presented with a board that every single number that could be used to identify a part has been laser etched off. They didn't want anyone to try to repair it. I have taken pictures of the parts I think could have caused this problem. there is only one near the channel 1 output. It is under a heat sink so it could be the offending part. I'll pull that heat sink in a bit here but I think it will be laser etched also. It's all SMD parts and me and SMD don't get along well at any time but if need be I can de-solder and solder them back in I just hate having to do it. I get a headache from eye strain. Also can I assume that the part of the board in the third photo is a boost converter I don't see a point in using a buck converter in a powered by 5V unit. Does anyone have any Idea where I turn now to repair it or is it now E-waste.

 

I was just using my waveform generator to trace a circuit when all of a sudden the signal just disappeared gone. I thought maybe I did something wrong but nope I didn't. reset didn't help and other than no output the unit seems to be working as it's supposed to. The only thing I have left is a signal injector I built in my teens. It works but It's a pain in the rear to use. I'll have to look into the one that quit on me and see if I can get it running again. It was not the top of the line either and plans were in the works for a new one but that was up the road a bit. Like I said great week first a blown up fish finder and now no signal generator. Lovely. :-(

This baffled me "reset didn't help and other than no output the unit seems to be working as it's supposed to".

How does a working signal generator behave when it doesn't produce an output signal?

 

Any outstanding IC?
Is it old?

 

This baffled me "reset didn't help and other than no output the unit seems to be working as it's supposed to".

How does a working signal generator behave when it doesn't produce an output signal?

Something like not having one. but I sort of do still have one just one of them is fiddley as hell and as unstable as it's operator. the other one is part of a multimeter that I use nearly exclusively and you can't have the signal generator at the same time it's doing other functions. So also a pain in the rear. So it's fix this thing or use the other stuff and work towards another one. that is going to cost at best 150.00 up to 270.00. the second one is feature rich but I don't need features I need reliability. Having to replace them every couple of years is not what I want. I have had my one meter since I was a snotty nose 15 year old and the other one I bought about 2 years ago. Here is what was under the heat sink at channel 1. As can be seen the identifying numbers have been laser etched off. I think I am in possession of a pile of E-waste here.