Stupid question, I am stumped. The new version Road Rage is all done, hooking it up to a Pasty Face.
Do I take off the power pad labeled -9v, or 9v?
And then hook that up to the round hole that says -9v on the main Pasty Face? I would assume -9 on the Road Rage, to -9 round pad on the Pasty Face, but am thinking I may also destroy something.
Thanks,
Pat
You got it! If you are using PNP germaniums, you must hook up the -9v pad from the RR to the -9V pad on the Pastyface. The Pastyface is a "positive ground" effect, so the RR uses a charge pump to get you that -9v you need to make the PNP transistors sing.
Thank you. One last question (hopefully) - do I run just one ground from the road rage to the pasty face, or two? The Pasty Face has two ground spots
You only need one ground to go to the PastyFace board. It doesn't need to come from the RR board really. You can ground both of them from a star location if you want. It's best to avoid setting up a situation where the grounds form a complete loop though.
Positive and negative ground are misleading terms. Ground is ground. Negative nine volts is negative nine volts, relative to ground. Pastyface runs on -9V. It's like saying you're driving on the center-right side of the road, rather than just the left side.
Thanks again. Finishing it tonight. You guys are great.
I have perfect bypass, but no power.
What does the square pad on the three pin voltage regulator indicate? I wonder if I have that in backwards. I put it in the way the picture looked, with the flat end toward the side.
I also put in every road rage component. Not sure if that was unnecessary for just positive ground.
Quote from: dont-tase-me-bro on May 11, 2014, 06:48:54 AM
I have perfect bypass, but no power.
What does the square pad on the three pin voltage regulator indicate? I wonder if I have that in backwards. I put it in the way the picture looked, with the flat end toward the side.
I also put in every road rage component. Not sure if that was unnecessary for just positive ground.
The square pad represents Pin 1 of the Volt Reg.
The orientation of the regulator would have the square pad going with the input pin of the regulator.
You don't need to use the regulator for the -9V output. You don't need most of the parts to get the 9V output. The doc has a section that will tel you what to omit. But, the -9V out should still work with those parts in place, it'll just be less efficient.
So, you aren't getting any power at the -9V pad?
One thing to note is that the orientation of an indicator LED will depend on which voltage you hook it up to, the input 9V or the -9V from the RR. Either will work, but you have get the orientation the right way around.
Thank you. That's part of where I went wrong. When I always looked at the omit section, I misinterpreted it, thinking -9 was not what I was doing.
If I were to not use a inverter, and just leave the pedal normal, could just use a positive tip power cable, like a moog pedal? I know you can't daisy chain them. My power supply has all the taps individually isolated.
I didn't jumper the pads on the 8 pin chip, because I bought the item below from small bear.
http://www.smallbearelec.com/servlet/Detail?no=794
one last thing I thought of - can I use any ground off of the road rage, or does it have to be the one next to the -9?
sorry for all the questions
Quote from: dont-tase-me-bro on May 11, 2014, 12:18:53 PM
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If I were to not use a inverter, and just leave the pedal normal, could just use a positive tip power cable, like a moog pedal? I know you can't daisy chain them. My power supply has all the taps individually isolated.
If the power supply is truly isolated, galvanically isolated, then you can power pedal from the same supply as others pedals that use a +9V power rail. But, you don't need to use a different power jack/plug arrangement. The standard negative tip will work fine. Think of it this way, the power supply doesn't care which side of the power you consider to be ground. It just has two potentials coming off of it, one 9 volts more positive than the other. If you hook the more positive side to ground, that makes it zero and the more negative side is at -9V compared to that. But, the reason it has to be isolated to do this is that if in one pedal you hook the positive side to ground and in another you hook the negative side to ground, you've created a dead short in the power supply. If it is a truly isolated supply, then each tap is an independent, floating potential and you can do with them whatever you want.
In general, I think it is still a good idea to pretend like you don't have an isolated supply and solve the issue with something like the RoadRage. The reason I say that is that if you need to get a power supply in an emergency, or borrow one some time, it's harder to find a truly isolated supply.
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I didn't jumper the pads on the 8 pin chip, because I bought the item below from small bear.
http://www.smallbearelec.com/servlet/Detail?no=794
You did this the right way. Also, I think the LT1054 is the better choice. It is overkill for this effect's supply current needs, but my experience with them has the LT1054 being the cleanest and most stable of the charge pumps I've tested.
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one last thing I thought of - can I use any ground off of the road rage, or does it have to be the one next to the -9?
sorry for all the questions
No problem at all on the questions, everyone here is happy to help. The ground pads of most any effect PCB will all be hooked together by the ground plane (or ground traces) on the PCB. So, unless there is something really subtle going on with the circuit, which ground pad you use won't matter.
But, I did just go look at the new 2014 RoadRage. If you are doing that one, you want to hook the positive terminal of the power supply to the + and the negative terminal (ground) to the - pads on the PCB. I assume the grounds and "-" pad are all still hooked directly to each other, but this could be one of those cases where using that pad for the ground connection has purpose in the layout. Charge pumps are more finicky than most circuits we work with. The "+" pad is important to hook the supply up to for sure, because this is the pad that is before the 1N5817 and the 10Ω filtering resistor.
Thank you again. This was definitely a learning experience, but I get the positive ground thing now. My next project is the bumble bee, which is in a drawer, ready to go with both PCBs, so now I know what to do for its road rage. I have some 1776 3pdt boards coming in the mail tomorrow, so I think I might finish the pasty face with that. after this, now I know to flip ground and power. my current road rage literally has every possible component soldered in
as I was doing this road rage and populating every single space, it did seem excessive to have that many components on the board. noob thinking was to omit nothing, because positive ground means +9, which isn't listed on the omit section
i have another set of different PNP transistors, so I'll make a another road raged pasty face in the near future. Thanks again for the help. I would not have figured this out
You're welcome, I'm glad I could help a bit. Like alanp said above, the term positive ground is misleading. It would be good if it would be replaced by something like negative power rail effect, but I'm afraid it's too entrenched to go away. The good side of having a completely populated RR is that you can use it to build a split rail design now ;). I keep a a fully populated RoadRage at hand with my breadboards because it's an easy way to try all sorts of circuits. Good luck on the next builds. It can be confusing at first, but after just a little experience the weird quirks get to be more predictable.
it's me again. sorry to bother you all.
I removed my road rage / connected 3pdt, and put in a 1776 3pdt board and a new switch. I have perfect bypass, but zero effect
from the PCB, I wired everything as normal, in to in, ground to ground, power to power, out to out.
from the DC jack, I flipped the wiring. Negative from the DC to the power pad (marked +), positive from the DC to the ground pad (marked -).
http://1776effects.com/wp-content/uploads/2012/01/3pdt_wiring.pdf
I am using a positive tip 9v wall adapter i have for a moog pedal. did I screw up by flipping the power wiring?
Thanks,
Pat
Yes. You flipped the wiring. Just wire up the 3pdt as normal (positive is positive etc). The charge pump takes care of making the voltage negative in the board itself.
Most guitar pedals are wired so the center pin is negative. I would highly recommend you get an adapter which has center pin negative just to keep everything the same.
Thank you. Just to clarify, when you say charge pump, do you mean the moog plug which is positive? I removed the road rage and put on a regular 1776 3pdt board. This is the plug
http://www.moogmusic.com/products/accessories/moogerfooger-power-supply
So if I just flip the wiring back to normal, the plug takes care of the inversion, and all is good?
Those 3pdt boards are pretty sweet, and are far noob friendlier than wiring the switch the traditional way
Quote from: dont-tase-me-bro on May 13, 2014, 01:45:03 AM
Thank you. Just to clarify, when you say charge pump, do you mean the moog plug which is positive? I removed the road rage and put on a regular 1776 3pdt board. This is the plug
http://www.moogmusic.com/products/accessories/moogerfooger-power-supply
So if I just flip the wiring back to normal, the plug takes care of the inversion, and all is good?
Those 3pdt boards are pretty sweet, and are far noob friendlier than wiring the switch the traditional way
Glad to help. :)
A "charge pump" is a microchip-looking package (usually a DIP8 which looks like a common TL072) and can either change a positive voltage to negative (+9v to -9v) and/or upconvert a voltage to almost double (ie: +9V to about +17v). Common charge pumps are the TC1044SCPA, LT1054, ICL7660, MAX1044.
For a positive ground effect the charge pump is useful as it isolates the power supply from your other pedals, while sharing a common ground. The Pastyface has a built in charge pump so it takes care of this for you. If you were building a board which was "postive ground" and didn't have a charge pump, you would use a RoadRage or similar circuit (which has the charge pump and circuit built in it) or power the effect by a 9V battery. Common positive circuits are some PNP Fuzzes and Rangemasters. They are not that common but do exist.
Other times, charge pumps are used to run a circuit at +18v from a +9V source (provided the components are rated for this voltage). Running at a higher voltage can increase headroom and lend a different (usually more cleaner) sound to a circuit. You have to be sure your caps and ICs are rated for the +18v...if you use a 16v rated cap and feed it more than that...you may hear a "pop" and the magic white smoke will be let out of the component.
Your Moog power adapter indeed will "work" however, most pedal effects have a "center-pin negative" DC jack. While you can wire your pedal up to be compatible with the Moog, if you plugged that Moog adapter into any Boss or Ibanez (or most common guitar pedals) you run the risk of blowing something up (either the protection diode in the pedal if it has one or the adapter itself).
It would be my suggestion to get a proper power supply (such as the Visual Sound One-Spot) or any other Boss/Ibanez +9V power adapter just to be on the safe side as I imagine you are going to build/amass more pedals as you are hooked now ;D. Plus if you lend a pedal to someone else, or borrow one, you will have the correct (more common) power supply. The One-Spot is a great choice, especially with the daisy-chain cable which is capable of powering numerous effects.
If you want something nicer (and much more expensive) the Fuel Tank Jr. or Pedal Power have isolated regulated outputs.
the road rage is definitely definitely being used on the bumble bee. I rewired the power to the normal terminals on the 1776. i get perfect bypass, and now instead of no effect, I get a low hum. I think I might just pull the transistors and start from scratch. I used the moog wall adapter so that should be good I think.
here's another dumb one - on the pasty pace pcb, where it says -9v and G, the power goes to the -9v pad?
Plugged it into this with a positive polarity cable. This already has a mix of pos and neg connected and has always worked
http://www.jimdunlop.com/product/mc403-power-system
Get bypass, no effect, no hum now with effect engaged
Maybe I'll yank the bumble bee's road rage, and go for switch number 3