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Yes chirping is caused by the clock signal. . Referring to this circuit, the addition of the buffers provided by the 4049 chip pretty much eliminates the chirping ..At least I have not noticed it with mine..But I'm no engineer.. I just wish someone would chime in with the knowledge to help out my problem!  Lol... Brian, Jacob. .Someone!

Good point, I wonder if meeting half way with a 50k trimmer may help? But having built one of these years ago with the original SAD1024 which chirped with clock noise even in the factory units I'd  played, I will say this unit doesn't have that kind of problem no doubt due to its well buffered clock signal. At the same time it's still having this feedback whine past 10 o clock on the feed back knob.. I may try changing that 100 to 50k and see what happens. . Brian said it was lowered to ease biasing. But I may try anything because it seems we're on our own  with this one I'm afraid.

No takers?

I've read those thanks..     As I said I get a decent flange with no clock noise, but to follow the feedback cal. instructions, it will not allow me to set the feedback control all the way clockwise without horrible whine.  Only about 10 o'clock.. That's with the T1 trimmer at minimum.  Turn that up and it goes crazy! 

Any experienced builders on the latest 2015 edition?  Of course if Brian would chime in that would be great!

Just completed the Current Lover and it sounds great but when I tried calibrating the T1/Feedback limit, with T1 at minimum I cant turn the feedback pot past 10 o'clock no matter where the clock /bias is set...

I'm doing something wrong or screwed up somewhere, please help!
Thanks!

Well there's been a lot of negative press on Mammoth but i will say this, they always get my orders right. I replaced the switch and it still does it, maybe not as bad, but still.  Another observation is the pedal that is ahead of it in the chain will pop when I turn it on when the Quasar is on..  Although it sounds fabulous, it seems like some DC is coming from the output.. I'll poke around and see if there are any errors on my part.
Strange indeed.

Dave

Jesus.. My bad.. sorry.. ADHD.. Just when I thought I would help someone..

Check the area where the 4.7uf cap is. When these go bad, it acts like a volume pedal.  So could be a broken trace possibly in that area of the circuit, like Jacob said.

Dave

Yeah that would be the 2nd out of a batch of 10 of the cheapies at Mammoth.  I guess it will pay to get the tougher ones.. Get what ya pay for!

Hi guys!  I looked around to see if there were any other problems similar to what i have, so if  missed it, I do apologize.

  This pedal sounds awesome!!  EXCEPT, it pops terribly when punching bypass switch in and out.  I tried adding a 4.7m pull down resistor to the input and output of the circuit it didnt help in the least.  Before I desolder the switch form the 3pdt board (smallbear) and try a new one, has anyone had any problems with this and could it just be the switch?

Thanks in advance..

Dave

That would be it!  At least i got some good typing practice! 

I get them at Mouser. I get the 1oz per inch or centimeter.. they have 1/2 oz too but I figure more is better since it may be more forgiving of heat.
But I am sure there are better and cheaper sources. P
erhaps someone could chime in where they get theirs. 

Dave

Oh and by the way, you should wear plastic surgical type gloves as Ferric stains and I'm sure it's not good to have absorb into your skin!. I also run the stove exhaust fan when warming the Ferric. The fumes are nasty.
And it depends on how large your board is as far as ironing times go. Little boards about 4 minutes, larger longer.

Dave

Well you have a couple options.  You  can do the positive photo resist method, which requires a dark room, special chemicals, etc.. It's nice, but by far the simplest, and most inexpensive method is the iron-on toner transfer method.  Which requires a laser printer or photocopier that uses toner (most public libraries have them).
I bought a simple monochrome Brother printer that I use only to make PCBs.  You will also need either glossy inkjet photo-paper or magazine paper to print your layout on.  There is a product available called PnP Blue.  It's a blue film that you can print on as well.  I personally hate the stuff, because it's fussy about iron temp, and it's a bit pricey at around $2 an 8x11 sheet, and I plain just suck with the stuff!
With the paper it's so much easier and all you have to do is crank the iron to the highest temp (make sure there is no water in the iron, you do NOT want steam!).  You then cut your board to size, flawlessly clean the blank board with cleanser under running water.  I use Bon Ami cleanser, it's real cheap. You don't want something with bleach like Comet has.  Clean it until water no longer beads on it. Make you sure you get the edges of the board really clean too. Then, DO NOT TOUCH CLEAN BOARD WITH YOU FINGERS!  When I print my layout, I first print it with my inkjet printer, then I cut the magazine or photo paper a bit larger than the printed layout, then i lay it on where it printed, take 2 pieces of scotch tape and tape the blank paper on, you want to have the blank paper enough wider than the layout so you can tape it without the toner printing on the tape. Just tape it with a piece on each side, no need to tape the top or bottom, just make sure it's nice and flat when you tape it on.  Then I feed into the manual feed of the laser printer, (set to the DARKEST setting) and print.
  You then align your printed toner layout onto the board and kind of work the iron on without letting the paper slide and press down FIRMLY for at least 3 minutes over the whole board, then I will spend pressing the edges as that is the most common place transfer errors happen.  After about 3 to 4 minutes of ironing I will lay a heavy book on the board for like 10 minutes, this helps the paper from bubbling up too bad.  Then soak the board in a bowel of warm water for a couple hours.  Then rub of the soaked paper with your fingers. If you did it right you should see the complete layout transferred. There will be a paper residue thats kind of a pain, but if you take VERY fine scotch brite to it, not too hard, it will clean it without harming the traces.  If you have a few missing pieces of trace or pad, use a black sharpie to draw them in again.
Then you etch in whatever sollutions you want to use that are available for the purpose. Muratic Acid, Ammonium Persulfate, Sodium Persulfate, or Ferric Chloride.  I use the Ferric.  Radio Shack sell bottles of it For $10. I put a pan of water on the stove and pour just enough sollution in a plastic Cool Whip bowel and warm the sollution a bit then put the board in.  You don't want the Ferric too hot though, then agitate it constantly until you see the copper start to disappear around the traces, and when it's gone immediately flush with cold water.  Then you're done.  I drill with my Dremel drill press, then tin mine in Tinnit Bright plate, which you can get from All Electronics and several other sources.  It protects the copper, looks cool, and makes soldering much easier!

  I'm assuming you never etched a board before, but if you have, ignore the redundant info..  Just how I do it.

Dave

I'll check that link out Dave, sounds interesting. Oops right, I put in a 1uf. I like it..