I built a Rangemaster workalike according to the
instructions found at the GEOFEX site. The problem is that
the instructions don't indicate WHICH wires coming from
WHICH lugs on the input and output jacks connect to
WHICH on a dpdt switch. For example: does the tip of
the input jack go unused? I'm not sure which lug on the
switch to connect the input cap to. And the black
battery wire? AAAArrrrgh!!!!!!!!! ???
calm down, gun powder.
http://www.tonepad.com/getFile.asp?id=76
My Hero! My (almost ) last question is: if I'm using a terminal strip, where does the red +9v lead go? (btw, I'm using an NPN transistor so I guess that the battery connections are reversed?)
Thanks!
With NPN, you'd reverse the electrolytic capacitor too.
Look at the schem to figure out where V+ hooks up.
I guess this can also help. Just please mind that the pull-down resistors are mistakenly put right on sockets which doesn't make much sense, hihihi :)
http://www.hoho.cz/osobni/rangemaster.gif
It shows 3PDT switch with 2 LEDs for 2 different input capacitors. It also shows an extra anti-pop wiring which was not necessary because the popping was due to wrongly put pull-downs.
Thanks to all for your help. It's getting there. I'm still having a wee problem. I'm using a PNP (OC44) not NPN as I incorrectly stated. I'm using a dpdt switch w/ no led indicator. The pedal works well on bypass. The schematic has the - end of the battery going to the switch. MY BIG QUESTION:Where does the remaining battery connection go? Does it share the lug with the input /input cap? ???
First of all: If you are using PNP, then your ground is positive (+)
Well on my picture the red wire is (+) and it goes to the ground . Wire this one the way as on my picture, using the input stereo socket as a power-switch (the input jack is in - battery is on). I mean:
1. from batery to a shorter input-socket lug
2. From input socket ground ring to the ground on your circuit
The other pole (-) goes from battery to teh spot on your circuit where input C 47uF, R 740k and one of the Pot lugs "meet each other". Basically what you have said already.
While the build instructions DO say that their will be DC on the pot, when I connect the other end of the battery to the terminal that you suggest3ed the signal is quite hot, there is a great deal of constant crackling, and even the pots on the GUITAR are noisy!!! I'm seem to have a lot of DC EVERYWHERE! I built this in a hammond box using a terminal strip. If I built the circuit on pcb would I be less likely to have this problem? The effect sounds very cool other than the snap, crackle etc...
the volume pot on the box crackles since it is placed right at the collector way. That's all right because there is usually no need to manipulate the volume pot at all. Sometimes pots crackle when you destroy them by heat while soldering (it's more common then one would imagine). This happened to me the last time with RM clone. When the pot is damaged you can hear sounds when you even touch the box or while using the foot-switch .... it drove me completely insane as i was not awared of that and had to test every single particle :icon_evil:
I noticed that the pot operates in the reverse direction, and this didn't change when I switched the lugs. I'll try testing/switching the pot. Thanks again
QuoteI'm seem to have a lot of DC EVERYWHERE!
That means that you don't have the input and output DC blocking capacitors hooked up properly. That's what the caps and input and output do - they block the internal DC from getting back to the guitar and out to the amp.
Thanks. I'll double check this. The original build instructions have the black battery wire going to the switch. but I wasn't able to make this work. When I connect to L5 (Power wire) it operates with the symptoms I described.
i guess the easiest way might be to put your instuctions/picture here so we know a bit nore what are we talking about ;)
http://www.geofex.com/Article_Folders/Rangemaster/atboost.pdf
Here's a link to the build instructions. It's a great article, and the device does sound very good other than the the extra crackling. (Thanks for staying with me on this one!)
I've been re-re-reading the build instructions for this project, and I've done everything "by the book". BUT... I noticed that there was a note in there about a gain factor above 150 not being useful for this project; The OC44 in this box tested at 192 (per the packaging). Could excessive gain from the transistor push to much DC through the circuit???