EEVblog Electronics Community Forum
Electronics => Projects, Designs, and Technical Stuff => Topic started by: tayexdrums on July 10, 2010, 03:39:43 pm
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I have searched all over the internet for the answer to this but I have yet to find any answer. Maybe someone will be able to help me=]
I have built the PCB using the toner transfer method and it came out pretty good. All I have to do now is buy the components and solder it up. However, on the Bill of Materials list it calls for one 150K (Ra)* resistor. I do not know what the "Ra" means. There is also a call for one 1 uF/NP capacitor and I can't figure out what the NP means. I'm thinking it could mean non-polarized. I will include the PDF of the schematic, layout, and bill of materials.
http://tonepad.com/getFile.asp?id=77
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RA = Resistor Array (Sometimes RN...)
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So what does that mean? I think it is just a way of notation for that resistor.
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Is it just a single resistor? If there's multiple resistors in one package then that's a Resistor Array (or Resistor Network). However, if there's just a single resistor then its just down to the naming conventions used by the program.
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It's the only resistor that has the Ra beside but its not the only resistor on the circuit board. I included a link to the PDF that has the schematic and layout.
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If you read the description to your own links http://tonepad.com/getFile.asp?id=77 (http://tonepad.com/getFile.asp?id=77) you will see Ra is a "Find on Test" style component, or more correctly you can change the behaviour by lowering its value.
In this case speed up the decay time of the attack/decay aspect of the muting circuit.
They even suggest a variable resistor by the schematic (as they do for the attack setting).
the circuit will most likely work fine with a standard resistor in each location, but they are showing you can play around if you so desire.
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Ohhh, I thought it might have been something like that. I read everything on the PDF but I just didn't put the two together. Thanks
:D