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Thanks, this isn't road rage specific but def LT1054 specific, I have 7815cv and 7915cv from Tayda and Futurlec which are MAR and CHN labelled at the bottom (country they're made maybe) and the ones from Futurlec (CHN) are working better... The ones from Tayda are reading all over the place on the diode test function on the mm.

The voltage drop of 1n4001's I have is all over the place too which is affecting input voltage to the regulators, not sure how this is affecting the output of the regs. Haven't tried 1n5817 yet, will try 1n60p.

Apparently the cap between pins 2 and 4 needs to be low ESL and ESR which can be achieved with a ceramic or tant in parallel. Same goes I think on the caps to ground at the voltage outputs.

This is quite pertinent, to me anyway.

http://brettcave.net/howto/circuits/PowerSupply_DualRail-LT1054-Straight.pdf
http://brettcave.net/howto/circuits/PowerSupply_DualRail-LT1054-Boosted.pdf

I am trying to draw upwards of 50mah though from the 1054, and have 2 of them paralleled, but the components seem to influence outcome more..

Andy

Back on the oiginal topic, if that is possible please.

I solved my problem.
The current the dirtbag draws (24 ma and slightly higher on startup) is on the edge of what the charge pump delivers. That is why it is dropping the voltage.
Apparently the combination of diodes, lt1054 and the 15 volt regulator ( i used a L7815CV) is more specific then I tought.
I breadboarded different combinations of different samples of the same part and noticed that this could make a difference of almost 1 to 2 volt!
Finally found the right combo that gives me a steady 14.95 volt with the dirtbag connected.
One to remember.

Thanks Djaaz for thinking wih me.
I
It is working fine now.
With 250k time pot (250k resistor parallel to that) instead of he 100k and a 270pf instead of the 250pf at the clock I have 560 ms of delay time.

Marc

Hey Marc, just wondering what that final combination was?

I am getting different results every time I build a supply using the LT1054. The voltage drop of the 1n4001 seems to change results the most. I've also found for some reason LM7815 seems to work alot more consistently than 7815CV?

Andy

Andy

Sorry, no I haven't noticed any problem with the stock values, even raising C35 to 1n only just makes a difference for me. Is it possible you might have the wrong value in 1 of those 2 spots?

Can't tell otherwise unfortunately.

Andy

Hey, C35 seems to have the most affect on the highs cutting from dry signal.

I have around 1n there which only just cuts very highs, I think, standard is 100pf.

Lowering C1 (470pf) might help too?

The trimmers do adjust the bbd voltage a little bit (.20v or so)

I have a 1k resistor to the striped end of a 7.5v 1w zener diode (other end goes to the ground pad there) then a 1n4148 to the remaining pad, where R19 would usually be. Striped end of the 1n4148 goes to that pad which bleeds of some more voltage so the chips get 7v.


          (R19)
           
*---1k-- --1n4148 | --*
            |
           --
      7.5v zener   
            |
            |
        ground

Andy

Maxim 1044 shouldn't whine. LT1054 will if pin 1 isn't bent up before going in the socket.

Hey, I might be a bit late buit I just checked out the MXR 117, which seems to have a really smooth and nice lfo driving it, which I imagine would sound amazing on the 'deluxe' aquaboy. Doesn't seem that much more complex than the current lfo judging by the schematic.

Hmm.. its def coming from the circuit, its by itself but its not boxed up though. Its a 50hz hum, NZ.. The hum eliminator is totally working for now at least. I've used a 1054 CN8 charge pump

Hey, does anyone else have a hum with their fatpants?

I've built v1 and v2 both with the same hum, but I am using s/h random 9v adaptors. I've minimized it using one of these

http://www.beavisaudio.com/projects/Huminator/index.htm

Anyone else with the hum?

Andy

Awesome man! is that a gain trim I see for the input level to the v3205's?

Also is it possible to make the minimum rate for the lfo really slow? like < 1hz?

Andy

Apparently, and from personal experience, the v3205 chips work best at 7v and get more distorted above 7.3, and I guess the same when 'undervolting'.

Check this build report and thread

http://www.madbeanpedals.com/forum/index.php?topic=1553.0

It describes adding a resistor in series from the + leg of c15 (33k, 39k) which lowers the signal  going into the chips, clearing up the delay sound. This is when using 2 chips though, not sure if its necessary or whether it works with just 1 chip.

Andy

I've fried a TCL2272 in the serendipity at 18v..,.

its gotta be a phaser? crossed fingers

Those diodes are upward of $20 each!, they must sound fantastic, did you have them already for a time?

Sorry I am tripppin, when bypassed the pedal is def quieter, so it is boosting but with the gain on full though and the tone control semi bypassed as described.

I'll remove the jumper to see.

The tone control on the pot is using this guide

http://www.beavisaudio.com/techpages/BigMuffToneControl/

with component values found from using the tone stack calculator further up the page

Could I put the tone control before the gain stage on the Fatpants? Also is there another cap or component which the whole signal passes through, other than C4, where the tone could go?

In and out in place of C2 maybe? would the pot need to be grounded in that case?

Sorry one more, would changing the resistor at the input R1 100k to a lower value raise the input level?

te choice
Andy

I'll post some audio soon, hopefully a video with an actual guitarist..

I've done this tone control and its behaving exactly how I'd hoped, except there *is* quite a volume drop.



Signal is on the white wire and goes to lug 3 of the pot (100kb) and goes back to the board from lug 2. Ground is connected by the green and purple from the other side of the cap from lug 1

I've found bridging lug 3 and 2, brings some volume back but the tone control is very mild after that.

Also removed R4 (47k) which makes it slightly louder again.

Now its pretty much at unity but its function as a booster has definitely gone...

The tone control is supposed to take away 8 - 10db at 12 oclock with the freq at both ends only minus 2 when the control is full up or full down

Does this seem correct? Is there anything anyone can see which is out of place, or just plain wrong??

cheers
andy

ps what looks like a 220n in C3 was just an experiment..