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Rangemaster help..Resistor values

Started by codyraptor, December 20, 2012, 05:39:48 PM

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codyraptor

I think I might be missing something on this build possibly. (still considered a noob)  I ordered the OC44 transistor from Smallbear and it came stating to use 43k for R3 and 3k for R5.  I'm guessing these were the values used to bias the transistor.  Neither of these values are in the actual build and there is no R5, so I'm getting a bit confused.  Should the transistor be fine going with the madbean values...or will I need to bias the transistor again?  If so..any good instructions out there on how to go about doing that?  Thanks!!!

DutchMF

I think I remember seeing some good info on that on Smallbears website... Not sure where though, but search a bit, or drop them an email.

Paul
"If you can't stand the heat, stay away from the soldering iron!"

midwayfair

Quote from: codyraptor on December 20, 2012, 05:39:48 PM
I think I might be missing something on this build possibly. (still considered a noob)  I ordered the OC44 transistor from Smallbear and it came stating to use 43k for R3 and 3k for R5.  I'm guessing these were the values used to bias the transistor.  Neither of these values are in the actual build and there is no R5, so I'm getting a bit confused.  Should the transistor be fine going with the madbean values...or will I need to bias the transistor again?  If so..any good instructions out there on how to go about doing that?  Thanks!!!

They're R1 and R2 in MadBean's version.

codyraptor

Gotcha...so I'm assuming the R5 at 3k is taking the place of R2 at 3.9k on madbean's parts..and the R3 at 43k is taking the place of R1 at 68k?  Then I can use the 470k for R3 as normal.

midwayfair

Quote from: codyraptor on December 20, 2012, 07:04:01 PM
Gotcha...so I'm assuming the R5 at 3k is taking the place of R2 at 3.9k on madbean's parts..and the R3 at 43k is taking the place of R1 at 68k?  Then I can use the 470k for R3 as normal.

I highly recommend reading RG Keen's article on Geofex for more information about these resistors.