Craig Anderton Frequency Booster and Questions

[CGP]

Hi this is my first attempt at converting a schematic into a veroboard layout, I haven't built it yet but should be able to verify soon. Can anyone see any glaring errors?
Also I want to make the frequency variable, on this design in the book (DIY Projects for Musicians) it suggests using some sort of switching to change between capacitors for C1* and C2*, would it not be easier to replace R5 with a potentiometer (10k in series with a small resistor i.e. 330ohm to set upper limit and 100nF caps for C1* and C2*) or is this going to cause issues with the rest of the circuit? Any help much appreciated

Frequency Booster Schematic.jpg

CA Frequency Booster.jpg

[kaycee]

You might want to compare with this, shows how to do the cap switching, Maplins have the double pole switches.

http://www.aronnelson.com/gallery/main. ... t.jpg.html

[CGP]

Cheers for pointing me in the direction of this layout, I have tried my own version and it works fine as a fixed boost. Experimenting with the pot in place of R5 did not work though seemed to work as another gain control rather than frequency sweeper. Guess I will go with the rotary switch option for now..

[limbe]

I used a miniature toggle switch,on-off-on 2poles for the booster.When the toggle is straight up,nothing is connected to the two poles in the middle.
That means that I could choose 3 of the 5 sounds that Craig suggested.I really don´t think I need more than that.It is also much cheaper than a rotary switch.

[HEAD]

Sorry to pull out this old thread - but can someone help me to figure what the S1 switch does in that schematic? Can't figure at the moment. I'm also very happy I found this original schematic - was searching for the original for an hour without any success. Was too lazy to reverse engineer the general guitar gadgets layout. :/ I'm building me my own home brewed basic audio peak freq workalike with this.

Regards
Helge

[marshmellow]

With the switch open the circuit is just a flat buffer, the frequency boost is disabled.

[HEAD]

With the switch open the circuit is just a flat buffer, the frequency boost is disabled.

Dankeschön! (Thanks!)

Nice. That's even better. So I can make the pedal buffered bypass which I would prefer anyway.

[HEAD]

If someone ever wants to build the booster with the GGG layout - there's something wrong with it I can't figure. http://www.generalguitargadgets.com/wp- ... ooster.pdf First error was easy to spot: in the transfer layout there's one connection missing between pin 1 and 2 of the op amp - but only in the transfer image. Weird. The second I haven't been able to spot. But it doesn't sound as vowel as the one I built up on vero using this layout (same cap value and caps): http://tagboardeffects.blogspot.de/2017 ... leper.html. Too bad. I don't like vero. I like tidy builts with a pcb.

[HEAD]

Just in case someone wants to build a Peak Freq workalike. This is with what I ended up. Surely could be a more sophisticated design but it works as it is. The buffer /clean blend could have been done with a another op amp or by using a quad op amp. But I was lazy and wanted to keep it simple. Nicely fits into an 1590B enclosure. Hope I got the credits right. If not let me know and I'll change that.

Regards
Helge

[HEAD]

Reworked the layout making the power rail less complicated an getting rid of one jumper. Haven't verified it. But I don't see any reason why I shouldnt work.

Cheers
Helge

Edit: Forgot to update the trace cuts in the mirrored view: Just don't do the ones at A11 and B8 and add one at C9 in the mirrored view.

[HEAD]

Finished my work-a-like. It's a bit messy inside and the optics are such a rip off of the basic audio style. But I really like Johns pedal aesthetics and always wanted to copy some of his enclosure style. So yep, here we are and I'm pretty happy with it.

Regards
Helge