From Fuzz Central, this is a modified Dallas Rangemaster treble booster. Uses an NPN germanium transistor so you can daisy chain it with other pedals that run off a positive 9 volt supply.
Hi David! I built one of these and it's amazing with AC187K. I only had an issue with it. The pedal isn't audible until I turn the boost knob around somewhere 12 oclock. Is that normal, or do I need to change something?
If I'm not terribly mistaken, I'm certain that I used logarithmic. But it wasn't a 9mm pot so, I did a lot of cable and pcb pushing to fit it in the enclosure. Maybe I just damaged the pot or another component doing so. I can't think of any other reason.
I´ve build a Rangemaster NPN versión with an AC127 transistor and switchable input caps, works great. I`ve tried to install 1M ohm pull down resistor mod but it change the tone a little. Don´t know why, pull down resistors are supposed to increase impedance and discharge the input/output caps and not affect the tone. Does somebody knows why this is happening? Thank you
Hi, longtime lurker and avid appreciator of your work. I’m experiencing a significant volume drop when the effect is engaged, well below unity. Can you think of any reason for this, or any way to mitigate it? I’m using a Russian MP37, btw. Thanks in advance!
I think i fixed it for me: I got rid of the Germanium diode, and the sound very much improved with unity being around 12. From what I have read this can count as normal. Concerning the diode mod, I have read that it makes sense to use it with especially leaky transistors. And in this case one has to match the diode with the transistor to get the best results. As my russian transistor has zero leakage, this mod isn't absolutely necessary for me. Hope this helps :-)
Hi David! I built one of these and it's amazing with AC187K. I only had an issue with it. The pedal isn't audible until I turn the boost knob around somewhere 12 oclock. Is that normal, or do I need to change something?
ReplyDeleteSounds like you may have used a linear taper pot. Try switching to a logarithmic/audio pot.
DeleteIf I'm not terribly mistaken, I'm certain that I used logarithmic. But it wasn't a 9mm pot so, I did a lot of cable and pcb pushing to fit it in the enclosure. Maybe I just damaged the pot or another component doing so. I can't think of any other reason.
DeleteAlso, I forgot to mention that when I turn the knob there is a little grinding noise. Can that be an indicator of a bad potentiometer?
DeleteThat's fairly common with Rangemasters (which is basically what the Range Blaster is). I wouldn't worry about it. I think mine does that too.
DeleteHey there,
ReplyDeleteIs the transistor CBE from top to bottom?
It is!
DeleteЧем заменит диод 1н34а? И собрал нет звука в чем может быть проблема транзистор мп37а
ReplyDeleteможет низкий коэффициент напряжения, попробуй МП38А
Deletehfe - 65 и выше
Delete3pdt ? or dpdt?
ReplyDeleteI´ve build a Rangemaster NPN versión with an AC127 transistor and switchable input caps, works great. I`ve tried to install 1M ohm pull down resistor mod but it change the tone a little. Don´t know why, pull down resistors are supposed to increase impedance and discharge the input/output caps and not affect the tone. Does somebody knows why this is happening? Thank you
ReplyDeleteI don't have access to any AC127's or AC187's as mentioned in this thread. Any easily available NPN CBE transistors I could substitute?
ReplyDeleteRussian MP38's have always worked for me in this kind of circuit.
DeleteHi, longtime lurker and avid appreciator of your work. I’m experiencing a significant volume drop when the effect is engaged, well below unity. Can you think of any reason for this, or any way to mitigate it? I’m using a Russian MP37, btw. Thanks in advance!
ReplyDeleteYou read my mind. I just finished mine as well (PNP Version) and have the same problem. I use Russian 1T308V.
DeleteI think i fixed it for me: I got rid of the Germanium diode, and the sound very much improved with unity being around 12. From what I have read this can count as normal.
DeleteConcerning the diode mod, I have read that it makes sense to use it with especially leaky transistors. And in this case one has to match the diode with the transistor to get the best results. As my russian transistor has zero leakage, this mod isn't absolutely necessary for me. Hope this helps :-)