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DIY Stompboxes => Building your own stompbox => Topic started by: richardk on May 30, 2012, 11:09:31 AM

Title: pulsar
Post by: richardk on May 30, 2012, 11:09:31 AM
hi everyone, i've just subscribed to the forum! ;D i would like to ask a question about an effect that i've just finished building, here is the schematic: http://www.tonepad.com/getFile.asp?id=29
It works fine but i would like to increase the rate of the tremolo, does anyone know how i could do that?
Title: Re: pulsar
Post by: Jdansti on May 30, 2012, 12:47:07 PM
Welcome to the forum, Richard! 

I wish I could give you an eact answer-I mainly wanted to welcome you. Hopefully someone with more knowledge will respond.

My guess would be to change the value of C8.  If you've already built this on a PCB, a simple test would be to temporarily hold another 0.47uf cap in parallel with C8 and see if the rate goes up or down.  This would be the equivalent of about 1uf. 

Again, welcome and please let us know how it turns out!

Title: Re: pulsar
Post by: Jdansti on May 30, 2012, 01:09:11 PM
BTW- there's a lot of information on the forum for this tremolo. Do a search on "Tonepad tremolo".
Title: Re: pulsar
Post by: richardk on May 30, 2012, 01:54:03 PM
thank you for the answer and the welcome john! ;D i'll try that mod, there is loads of info on this forum, it's not bearly comparable to the italian forums!
Title: Re: pulsar
Post by: richardk on May 31, 2012, 10:47:40 AM
in the end i put an LED between the collector of Q2 and the ground...now i've got a pulsating light and more rate! :D
Title: Re: pulsar
Post by: Joseeduardosn on May 31, 2012, 08:06:07 PM
Effect works? Because many say the tonepad schematic errors. I armed myself and did not work.
Title: Re: pulsar
Post by: Jdansti on May 31, 2012, 11:18:26 PM
Quote from: richardk on May 31, 2012, 10:47:40 AM
in the end i put an LED between the collector of Q2 and the ground...now i've got a pulsating light and more rate! :D

Cool!  Two birds with one stone!  I'm thinking that a tremolo will be my next project after I clear my plate of the several that I've already got going.  I'll have to remember that mod. Thanks for sharing!
Title: Re: pulsar
Post by: richardk on June 01, 2012, 06:36:02 AM
Quote from: Joseeduardosn on May 31, 2012, 08:06:07 PM
Effect works? Because many say the tonepad schematic errors. I armed myself and did not work.
well actually it muddys up a bit the sound, and it has quite a big volume drop...but i think that can be resolved:)
Title: Re: pulsar
Post by: richardk on June 01, 2012, 08:58:22 AM
Quote from: Jdansti on May 31, 2012, 11:18:26 PM
Quote from: richardk on May 31, 2012, 10:47:40 AM
in the end i put an LED between the collector of Q2 and the ground...now i've got a pulsating light and more rate! :D

Cool!  Two birds with one stone!  I'm thinking that a tremolo will be my next project after I clear my plate of the several that I've already got going.  I'll have to remember that mod. Thanks for sharing!
you're welcome! here's a thread with a few improvements i'm going to try today:
http://www.diystompboxes.com/smfforum/index.php?topic=52531.msg397020#msg397020
i also think i'm going to stick an AMZ buffer on the output...
Title: Re: pulsar
Post by: hannibal827 on June 01, 2012, 08:33:59 PM
Quote from: Joseeduardosn on May 31, 2012, 08:06:07 PMBecause many say the tonepad schematic errors.

If you build the circuit from the schematic, it works fine.  The pcb layout has an error [having to do with the rate pot--read the build reports on the Tonepad site].

In my build, I perceived a slight volume drop using the suggested value for R4 [33k].  Increasing R4 to 47k solved the problem for me.
Title: Re: pulsar
Post by: richardk on June 02, 2012, 09:46:38 AM
ok, i'm fed up with this pedal: C1=.047uf  R4=150k that's what works for me...it's cleared up quite a bit and now it sounds boosted! ;D :icon_twisted:
i will post some photos when the job is finished...
Title: Re: pulsar
Post by: Joseeduardosn on June 04, 2012, 04:42:56 PM
Quote from: hannibal827 on June 01, 2012, 08:33:59 PM
Quote from: Joseeduardosn on May 31, 2012, 08:06:07 PMBecause many say the tonepad schematic errors.

If you build the circuit from the schematic, it works fine.  The pcb layout has an error [having to do with the rate pot--read the build reports on the Tonepad site].

In my build, I perceived a slight volume drop using the suggested value for R4 [33k].  Increasing R4 to 47k solved the problem for me.
Thanks!
Will try to design the PCB with software, and follow your advice of resistance. I made the EA tremolo and distorts something, but very little, very little, a certain volume. OffTopic: What software do you use to design the PCB?
Title: Re: pulsar
Post by: hannibal827 on June 04, 2012, 09:00:02 PM
I generally build on perfboard, so I don't use PCBs.  I use DIY layout to work out my perf layouts, though.

The Tonepad PCB can be used if you do the rate pot fix that is illustrated here:
http://users.telenet.be/orangefg/pulsar_pcb_fix.gif

Regarding the R4 substitution, test it out on your breadboard and see what value works best.  47k worked for me; 150k seems to have worked for richardK.  It's subjective.

Good luck!
Title: Re: pulsar
Post by: Joseeduardosn on June 06, 2012, 12:31:37 AM
Thanks!...
I plucked up the Pulsar did not work. I made the cut and ran. But nothing, began to pop out of nowhere, because so far made ​​no noise, unless the change is made​​. Anyway, try again. Thanks again.
Title: Re: pulsar
Post by: hannibal827 on June 06, 2012, 08:34:57 AM
Sorry it isn't working.

Try reading this thread http://www.diystompboxes.com/smfforum/index.php?topic=29816.0, and the build reports at Tonepad, or even emailing Francisco.  The circuit does work; keep trying and you'll get it.
Title: Re: pulsar
Post by: Jdansti on June 06, 2012, 09:53:42 AM
Quote from: Joseeduardosn on June 06, 2012, 12:31:37 AM
Thanks!...
I plucked up the Pulsar did not work. I made the cut and ran. But nothing, began to pop out of nowhere, because so far made ​​no noise, unless the change is made​​. Anyway, try again. Thanks again.

Could you post photos of both sides of your board and the off board components?
Title: Re: pulsar
Post by: richardk on June 08, 2012, 09:26:14 AM
here is, finished!

http://imageshack.us/photo/my-images/337/sdc10456ql.jpg/
http://imageshack.us/photo/my-images/441/sdc10458z.jpg/

not one of my best builds, i think someone is going to have a present of it very soon... ;D
Title: Re: pulsar
Post by: Jdansti on June 08, 2012, 10:54:07 AM
Quote from: richardk on June 08, 2012, 09:26:14 AM
here is, finished!

http://imageshack.us/photo/my-images/337/sdc10456ql.jpg/
http://imageshack.us/photo/my-images/441/sdc10458z.jpg/

not one of my best builds, i think someone is going to have a present of it very soon... ;D

Still a nice build-looks better than most of mine! :)
Title: Re: pulsar
Post by: Joseeduardosn on June 09, 2012, 08:46:14 PM
anyone have any proven layout? because the software I have will not be used. Thanks.
Title: Re: pulsar
Post by: richardk on June 09, 2012, 09:20:23 PM
i used the tone pad one, you can fix it with a very simple mod...take a look at the thread above...
Title: Re: pulsar
Post by: Joseeduardosn on June 11, 2012, 07:25:27 PM
ok... thanks!..