WOLF COMPUTER

[eatyourguitar]

as far as I know mellowtone Eric is never coming back. been gone for a while so here we go. found these two things floating around. the problem with a regular starve control is you will eventually have a transistor with C and E sitting on the power rails and you will have your unprotected base of another transistor pulled up directly to V+ with no current limiting resistor. I don't like it. therefor I chose the schematic that looks like no warranty dead pedals come back.
http://www.neuron.xyz/Wolf%20Computer_schem.pdf

http://www.neuron.xyz/wolfcomputer.gif


I started working on my own and made a 7 knob. PCB soon. not sure about punch being 100k or 500k. not sure about the tone stack at the out. I might add a ground lift switch on the cap. might change the pot and cap values slightly. I don't want to change the sound of the wolf computer by adding a tone stack.

http://www.neuron.xyz/WOLF7SCHEM.jpg

[multi_s]

i think the base current actually is limited by the 1k on the emitter side. without thinking too hard you can see that the current is limited to worst case (Vcc-Vbe)/1K < 10mA, less than 10% of max Ib for a run of the mill 2n3904.

looks safe to me?

s

[eatyourguitar]

i think the base current actually is limited by the 1k on the emitter side. without thinking too hard you can see that the current is limited to worst case (Vcc-Vbe)/1K < 10mA, less than 10% of max Ib for a run of the mill 2n3904.

looks safe to me?

s

what did you get for Vbe? most datasheets say Vbe > 5v = you pooped your pants go buy another 2N3904. I know this depends completely on thermal dissipation of the delicate BE junction and this depends again on Ice which we can see is limited by 1K + 10K. but it is my understanding that the 5v rule is more likely followed in some way most of the time and people may accidentally be putting ESD protection into the design of many transistor circuits. the texas instruments book I have on transistors was pretty paranoid about this stuff. probably because of the potential applications it was intended for are much more critical than the toys we build with them.

but anyway, I can go back to a regular starve control. in that case I can maybe bring back the coarse and fine starve that was on the deluxe wolf computer. there was debate over 5k vs 10k. I could do 10KA with a 1KB in series it should be very versatile at the expense of being less convenient. anyone building this can change the starve control how they want. you have options. do I put the starve pads on the PCB or off board? are people buying more PCB's with board mounted pots or off-board pots?

[eatyourguitar]

[Jero]

Eric was here just a couple months ago, and sold some Wolfs via Ebay

[eatyourguitar]

Eric was here just a couple months ago, and sold some Wolfs via Ebay

do you have a link to the ebay? I could not find a mellowtone website anywhere. I searched all the forums and never found anything from him or mentioning him in 2016. there were threads on ILF where the moderators are saying he stole money and never delivered the pedals. I thought he was shamed and never to return to ILF. was ebay his only appearance? I am also not selling a 4 knob wolf computer so I might just do it anyway. I would respect his original circuit if he is still selling pedals. I know the rules.

[multi_s]

i think the base current actually is limited by the 1k on the emitter side. without thinking too hard you can see that the current is limited to worst case (Vcc-Vbe)/1K < 10mA, less than 10% of max Ib for a run of the mill 2n3904.

looks safe to me?

s

what did you get for Vbe? most datasheets say Vbe > 5v = you pooped your pants go buy another 2N3904. I know this depends completely on thermal dissipation of the delicate BE junction and this depends again on Ice which we can see is limited by 1K + 10K. but it is my understanding that the 5v rule is more likely followed in some way most of the time and people may accidentally be putting ESD protection into the design of many transistor circuits. the texas instruments book I have on transistors was pretty paranoid about this stuff. probably because of the potential applications it was intended for are much more critical than the toys we build with them.

i think you have Veb max and Vbe confused. Vbe will almost always be ~.7volts fora si transistor if Vb > Ve. no pants will be pooped. You can see these specs on a data sheet. For Veb to be 5 volts it means that Ve is greater than Vb by 5 volts. In the schem Vb will most certainly be greater than Ve, (ie Veb is actually negative).

[eatyourguitar]

I see it now in the datasheet it is reverse breakdown voltage -6v for fairchild 2N3904. the datasheet here has it listed as 6v not -6v but I do understand it is actually saying -6v Vbe will destroy the 2N3904 now that you explained it to me. it makes sense when you consider it says breakdown (not forward) voltage.

http://www.mouser.com/ds/2/149/2N3904-82270.pdf

[veteransdaypoppy]

Eric was here just a couple months ago, and sold some Wolfs via Ebay

do you have a link to the ebay? I could not find a mellowtone website anywhere. I searched all the forums and never found anything from him or mentioning him in 2016. there were threads on ILF where the moderators are saying he stole money and never delivered the pedals. I thought he was shamed and never to return to ILF. was ebay his only appearance? I am also not selling a 4 knob wolf computer so I might just do it anyway. I would respect his original circuit if he is still selling pedals. I know the rules.

As far as I know, Eric was using his "letsgocoyote" eBay account to sell some WCs some time ago, but it appears as though his eBay acct has been inactive for ~6mos.

I have one of these deluxe guys from years ago:


It's been on my board forever. I'm thinking of building a clone though, so

[skullservant]

He sold me a guitar around Thanksgiving

[multi_s]

I see it now in the datasheet it is reverse breakdown voltage -6v for fairchild 2N3904. the datasheet here has it listed as 6v not -6v but I do understand it is actually saying -6v Vbe will destroy the 2N3904 now that you explained it to me. it makes sense when you consider it says breakdown (not forward) voltage.

http://www.mouser.com/ds/2/149/2N3904-82270.pdf

ya usually the naming convention/polarity implied is, say on this data sheet, they call it "Emitter-Base breakdown Voltage" and give 6V. The key is the order they list the terminals. Emitter to base, as if conventional current was flowing emitter to base and you measured with the positive side of a voltmeter on the first terminal mentioned. This is the reverse of normal operation as you said. Like saying Vbe max is -6V, as you said exactly.

But now if you look at the "Base emitter saturation voltage" that is implying, since base is mentioned first, conventional current flows from base to emitter, then this is the typical voltage drop.

They are both measurements of the same 2 terminals, but under different operating conditions.

[eatyourguitar]

I have one of these deluxe guys from years ago:


It's been on my board forever. I'm thinking of building a clone though, so

all my research would indicate the deluxe you have is just a wolf computer with a high five boost in front. the footswitch toggles the boost. i just don't know if the right footswitch is bypass all or does it just work like two pedals in one box? does anyone have schematic for the high five? is it opamp, fet, or transistor?

[veteransdaypoppy]

The right footswitch is not a bypass all... It works like two pedals in one box. Also, it's always sounded more like WC -> Boost than Boost -> WC to me, but i could be wrong.

[eatyourguitar]

If you start with a not so bright fuzz and then you kick on the boost does it get brighter? Or does it stay the same fuzz with more feedback, noise, compression?

[eatyourguitar]

comming soon