Vol. 26: The Luna Mod

Simple, addictive sound effects looper.

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� MAKE: AMENDS Errata for This Article

Correction for page 80
In the schematic for Volume 26's Luna Mod sound looper, the labels for Tempo and Sound were mistakenly reversed. The corrected schematic is online at makezine.com/26/lunamod and makeprojects.com/project/t/974.

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Showing messages 1 through 31 of 31.

LunaMod goes into beep mode
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Hello, I've finally finished my LunaMod and have a weird problem. The Picaxe code loaded correctly once I selected the 08M2 models number. When I turn it on it will work for a little while, but then goes into a beeping mode. Just "beep" "beep" "beep" with about a 1 second interval.If I fiddle with the knobs it will start working again for a while but then go back into "beep" mode. Any ideas? I've checked the circuit board for shorts. I'm guessing something with the capacitors.
Posted by stren on February 20, 2012 at 06:55:07 Pacific Time

Minor typo in the schematic
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FYI: It appears the labels Tempo and Sound are reversed on the schematic.

It's not a bit issue, but if you were hoping to replace the Sound pot with an photo resistor, for example, you might not get the results you expected.

Posted by zazenmaster on January 01, 2012 at 17:12:54 Pacific Time

Minor typo in the schematic
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Thanks for your sharp eyes! We just posted a corrected schematic above.
Posted by Laura Cochrane on January 09, 2012 at 15:28:28 Pacific Time

Fun with a photocell
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http://www.youtube.com/watch?v=NwDMHcYwS2o
Posted by radial77 on December 18, 2011 at 08:37:50 Pacific Time

Schematic without programmer
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I found a link to a schematic that doesn't include the programming input: http://www.instructables.com/files/orig/FGE/IKDL/GAKTU7C8/FGEIKDLGAKTU7C8.pdf
Posted by radial77 on December 18, 2011 at 08:33:53 Pacific Time

Luna Mod program file
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When I went to get the program file off the link up there ^ I realised that there wasn't as much writing there as it shows in the original article and it only used 60 bytes out of 256 instead of 81 in the article. Should i be concerned?
Posted by CitizenKane on November 20, 2011 at 21:17:06 Pacific Time

Not Sure How To Wire Programming Socket
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When I expose the terminals on the 1/8 Audio jack there are three possible locations Not sure where to connect each wire
Posted by dcohen32 on October 25, 2011 at 09:33:05 Pacific Time

My Luna Mod
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Heres a link to my Luna Mod made via these plans. Great build, had lots of fun. Repackaging it to fit into a new, very cool, enclosure now. Thanks
Posted by pbecker83 on September 25, 2011 at 18:13:43 Pacific Time

My Luna Mod
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Oh ya the link lol

http://youtu.be/catGkcbnS8E
Posted by pbecker83 on September 25, 2011 at 18:14:28 Pacific Time

08m2 chip instead of 08m?
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I'm new to picaxe and just got together all the stuff for this project. I have a 08m2 chip though instead of the listed 08m. Will the 08m2 work? If it needs different code does anybody have it?
Posted by j1234567 on September 01, 2011 at 10:58:00 Pacific Time

08m2 chip instead of 08m?
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The 08M2 is backwards compatible with the luna mod program. Just be sure you have the most recent Picaxe programming software and have selected 08M2 under Options > Mode.
Posted by MendoMaker on October 04, 2011 at 08:53:53 Pacific Time

Toggle Switch
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If I'm not mistaken, you only need a Single-Pole-Single-Throw switch for this project. So whether you have the switch with 2 contacts or 3 doesn't matter. Just put them in the right place. I can't remember the horizontal, but the vertical will have contacts at 2 and 3. It's been a while since I've worked on this, so you may want to look at the circuit to make sure. Either 1 or 3 goes nowhere.
Posted by JGoulds on August 09, 2011 at 11:50:03 Pacific Time

Toggle switch
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The radio shack toggle switch I got only has two pins. Should pin 3 go into 14,1 or 14,3?
Posted by recker on August 06, 2011 at 19:21:53 Pacific Time

Toggle switch
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Putting pin 3 at (14,1) will work regardless of a two or three pin switch.
Posted by MendoMaker on October 04, 2011 at 08:59:29 Pacific Time

voltag regulator
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hello! i have a little problem understanding how the voltage regulator is connected.

article says:
pin1 to 3,5
pin3 to 3,3

what about pin2? am i supposed to cut it?

ty
Posted by mrks.js on July 14, 2011 at 16:05:21 Pacific Time

voltag regulator
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Don't cut pin 2, just solder it in place when you have pins 1 and 3 in the correct positions.
Cheers,
Brian.
Posted by grandtippler on July 14, 2011 at 17:22:09 Pacific Time

voltag regulator
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so pin2 goes into 3,4?
Posted by mrks.js on July 15, 2011 at 01:11:39 Pacific Time

Please help
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I also just got done soldering and putting together my board, and when I loaded the software, got the same error:

"symbol Sw_Write = pin3 ;write switch
^

Error: Unknown symbol - pin3"

Does anyone out there know what this means?
Posted by wesp42 on July 05, 2011 at 07:19:46 Pacific Time

Please help
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I'm not 100% sure what has gone wrong but make sure you have the controller type set to picaxe o8m in the options menu.
Cheers,
Brian

Posted by grandtippler on July 14, 2011 at 17:26:47 Pacific Time

Please help
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Brian Thanks,
after setting options to 08M, the program syntax was checked.
Posted by wesp42 on July 14, 2011 at 19:12:11 Pacific Time

Please help
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I gave this a quick look - copied and pasted the code from the page here into the PicAxe editor and clicked the "Syntax" button on the toolbar. It all checked out OK.

See if you're getting a cut-and-paste error on that line of text. It's possible your browser may be adding a character the editor doesn't like. If you just copy the line giving you trouble:

symbol Sw_Write = pin3 ;write switch

into the editor and then click the Syntax button, you should see it gets identified as a Variable on the right side of the window. If it does that then you should be OK.
Posted by Jeff_Haas on July 06, 2011 at 01:18:52 Pacific Time

picaxe compile error
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my compiler bombs out on the first line of code:
"symbol Sw_Write = pin3 ;write switch
Error: Unknown symbol - pin3"
Any hints?
Posted by j0nh3nry on July 01, 2011 at 15:27:14 Pacific Time

Luna mod capacitors
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What voltage do you need for the 10nF and 100nF capacitors?
Posted by KroneckerDelta on May 26, 2011 at 22:23:42 Pacific Time

Luna mod capacitors
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Just use normal ceramic capacitors, I'm not sure if they have a voltage rating, if they do, anything over 5volts will be fine.
Posted by grandtippler on May 29, 2011 at 18:00:31 Pacific Time

Luna Mod to External Speaker?
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I modded the mod a bit and fit a single 8ohm 0.5 watt speaker into my case and would like to have the option to listen to the luna on this speaker in case i don't have the opportunity to plug it into a proper amp. I used a 2 conductor mono jack that shuts off the speaker when it is plugged in and this all works fine... however the speaker is way too quiet. How can i add a super simple and cheap amp to my speaker that is powered by the same 9volt battery? It would be nice to have some volume control but I would settle for just 'louder'. Thanks!
Posted by elstratego on May 26, 2011 at 17:45:30 Pacific Time

Luna Mod to External Speaker?
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An LM386 amp would be simple enough to add to the project. And, if you chose not to add a potentiometer for the volume or gain, it would hide nicely inside your project without having to modify it any further.

Really, any small low power amp will work in this situation.
Posted by alienmeatsack on June 13, 2011 at 16:13:58 Pacific Time

Luna Mod to External Speaker?
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Thanks guys! After a little research I came across a small amp kit that uses the LM386 chip... http://www.canakit.com/0-5w-universal-mini-amplifier-kit-ck026-uk026.html I was able to build it and hook it up to the lunamod, the speaker (with vol control) and share the 9v battery as well... worked great and I'm pleased to say I finished my synth and it's LOUD! Now to mod the code...
Posted by elstratego on June 13, 2011 at 19:02:38 Pacific Time

Power Adapter?
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What voltage/amperage would you suggest so you can plug the Luna Mod in to the wall?
Posted by jahwa on May 25, 2011 at 08:40:22 Pacific Time

Luna Mod Audio Jack
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Does the audio output jack have to be mono, or is there a way (without doing it the way it is in the design and getting an adaptor) to hook it up to stereo headphones?
Posted by jethst on May 14, 2011 at 23:35:22 Pacific Time

Luna Mod Audio Jack
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Just use a stereo jack instead. If you get a 1/8in stereo jack you can use normal headphones.
Posted by grandtippler on May 15, 2011 at 02:22:17 Pacific Time

Luna Mod Audio Jack
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Thanks!
Posted by jethst on June 24, 2011 at 12:13:29 Pacific Time

Showing messages 1 through 31 of 31.

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