so have you made any pcb making to sell process, a very nice tidy worth buying board
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by the sounds of it you could order 12 + of these and sell them to cover your cost + . I think everyone is interested in this one .
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I was Finally able too get past this Design Error. After A lot of reading Books and Trial and error I was able to linearly Display the Voltage output on a Red and Blue LED By Converting the Voltage too a Current Source For the LED
Thanks for Pointing me in the Right Direction. I know it was a small problem, But I really liked Working on fixing this error.
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So do you now have pcbâs to sell? Great pics and beautiful design so far.
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I donât have any boards to sell yet. I plan on redoing the board layout correcting a few errors and some further testing Here is where the project updates are
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I can wait , will buy 2 definitely and just let me know, thanks happy synthing
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Yeah this would be great! Sign me up for 1 please!
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Maybe my brain is too tired and I should just go to bed, but what difference in effect is there between the range pot and the passive attenuator pot? It looks like the former sets the gain of the first amplifier stage and the second attenuates the output of the second stage. Why is that not redundant?
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It can be kinda redundant. But the attenuation pot allows you too turn off the signal completely if needed. Thanks for your input. If you have any-other suggestions for the design for usability I would like to hear it.
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I am thinking of removing the passive attenuator section. Because it is pretty redundant and will look into adding a inverted X/Y Jack as a option. Project Update
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One thing about inverters and offsets, if you just add an offset and then have outputs before and after an inverter stage, then youâre also inverting the offset, meaning that if you turn the offset knob up then the offset on the non-inverted output goes up, but the offset on the inverted output goes down. Or vice versa. Which isnât the end of the world but itâs a little counterintuitive.
If you look at Ray Wilsonâs Quad DC Mixer he does something more complicated to make the offset go the same way on both outputs. It took me some time to figure out what he was doing, especially since he has multiple inputs mixing and that affects the scale of the offset. But what it boils down to is he adds an offset in the first (inverting) stage, and then he adds double the same offset in the second stage. So the first stage output is -signal+offset and the second stage is -(-signal+offset)+2*offset = signal+offset. Now if, for instance, youâve offset a ±5 V signal to make a 0 to 10 V signal, then the inverted signal also is in the 0 to 10 V range instead of 0 to -10 V.
But things get even more complicated if, unlike Wilson, you have a variable gain. Then you have to add double the offset times the gain to the second stage, which is a complete mess. Or you have to separate the first stage into two, doing the gain in one stage, then adding the offset in the second stage, then adding double the offset in the third stage. Which means the amount of offset is independent of the gain⊠which makes more sense to me anyway.
Or you can do it Stereopingâs way, which is simpler. But more oddly behaved.
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Thank you for the reading material. Iâll read more into it. Probably wont do a full redesign. Might just have it as a optional feature.
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