Author Topic: Dirtbag Delay  (Read 13734 times)

jkokura

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Re: Dirtbag Delay
« Reply #60 on: December 07, 2011, 09:19:54 PM »

Got a breadboard and a spare 4047?

It's not a great way to test it but if you find the schematic for the EHX Full Double Tracker (I redrew the original, you should be able to find the 3005 version I did on Freestompboxes) remove R15,16,17 - C12 & D2 and then wire a 100k pot between Pins 2 & 3 of the 4047 which will now be your delay pot. Oh and ignore all the power supply stuff.

You should be able to test the chips to some extent with that and it's ridiculously simple, don't expect great signal quality and definitley expect some clock whine but it might just help to give you an idea, if only to find out if they work at all.

Got a link for all that? The reason I was waiting was because I don't have all the parts, but I might scrounge and see if I have a 4047, though I doubt I do.

Jacob
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Scruffie

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Re: Dirtbag Delay
« Reply #61 on: December 07, 2011, 10:14:04 PM »
MN3101? 4013? 4046? You can even make a clock with 2 NPN transistors at a push.

I'm too low on my net allowance to go searching but on Freestompboxes, I did post a redrawn schematic or an EHX Full Double Tracking/Tracker, give google a search.

Yes I gathered that's why you're waiting but if you have a reasonable breadboard stock and even a load of wrong values, you should be able to pull something off.

You could even make it simpler and just have an input and output buffer with opamps or transistors, a 100k trim connected via 9V & Gnd biasing the 3005 and the clock although with no low pass filtering it will become even harder to tell if the poor sound & clock whine is the bbd or the poor circuitry.
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nzCdog

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Re: Dirtbag Delay
« Reply #63 on: December 08, 2011, 09:44:27 PM »
Very cool mod Josh... so how much delay time can you squeeze out of your Dirtbag now??

gtr2

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Re: Dirtbag Delay
« Reply #64 on: December 09, 2011, 12:49:13 PM »
Around 750ms with no modulation

When I add the modulation I get clock wine at the longest delay settings.

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claytushaywood

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Re: Dirtbag Delay
« Reply #65 on: December 30, 2011, 05:20:17 PM »
i'm new to this forum... and ive been searching quite a bit with the box but i cannot find anything on sourcing mn3005's... i'm sure this has been covered... but it appears not.  if someone could help me get some i would be forever indebted!!!

jkokura

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Re: Dirtbag Delay
« Reply #66 on: December 30, 2011, 05:54:34 PM »
There are no guaranteed methods. If you have some though, let me know cause I need 4.

Jacob
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