Wiring Bundle?

[Steve Mavronis]

If you bundle say 4 PCB wires (input, output, voltage, ground) plus wiring from 2 pots together is that an issue? I remember reading something  in the past about not bundling power wires with signal wires but want to make sure.

[mth5044]

Subscribed, I am curious also.

From what I read, wires should cross at 90 degree angles, making cross like patterns where ever the meat.

[petemoore]

  Inductance.
  AC pulses when circuit AC is 'let in' from the power supply may ripple the power supply, try a BFC.
  Sensative input wires may catch inductance from 'dc' wires that have some AC ripple on them, mainly a deal with amps [probably because there is very little bundling because of the inductance issues, of course it will vary as the definition of ''what a circuit can get away with'' does.
  Neatness aside, unless ready to undertake the re-prototyping which might be needed or put up with noise levels that are higher than 'conventional' layouts [keeping sensative input wires away from, or X crossing, so as not to form inductance like transoformer].
  9v being low tension, chances are you could get away with some of it, personally, unless low noise was the result I'd feel strong inclination to build a comparator circuit box with attention to convention [commonly accepted wiring practices] to use as noise floor reference.

[Steve Mavronis]

In my internal layout because of the input/output jacks vs PCB wire pad locations due to using soldered mounted pots, the 4 wires criss-cross from opposite sides. This pedal is somehow quieter than expected and it shouldn't be the case (with a 741) so maybe the wiring pattern is helping to cancel some noise as they weave in and out past each other (at near right angles) on their way to the strain relief loop holes? If you follow the wire colors in my pedal gut shot below you can see exactly what I mean:



This internal arrangement was to be like a template for my future builds. But I may be forced not use the right-angled PCB mounted pots any more, since they are hard to find in stock at any given time when I want to place a parts order (like right now) which really frustrates me!

And going to regular pot lugs insead will add extra wires to the mix. This is unfortunate because I really wanted to avoid a rats nest inside which is why I went for PCB mounted pots in the first place, plus it does provide a nice solid fixed PCB mount to the enclosure. I had hoped to keep a standard of clean and tidy wiring in my builds but oh well.

[John Lyons]

Keeping the output away from the input is always a good thing.
Sometimes it's not THAT sensitive but it is good practice
especially in distortion/fuzz/OD circuits.

Power connections are less of an issue but do what you can.

[stringsthings]

... I may be forced not use the right-angled PCB mounted pots any more, since they are hard to find in stock at any given time when I want to place a parts order (like right now) which really frustrates me! ..

that's an excellent looking pedal.

why let a little thing like an out of stock part frustrate you when you know that you'll eventually be able to build exactly what you want with the component(s) that you want?

[Steve Mavronis]

that's an excellent looking pedal. why let a little thing like an out of stock part frustrate you when you know that you'll eventually be able to build exactly what you want with the component(s) that you want?

Thanks and good point. Not meaning to deviate too much from the wiring topic but waiting 2-3 months for any one part just sux. By then some other part could become out of stock. I could order things piece meal here and there to cover my bases but then the extra shipping costs add up and I order everything from 2 places to get everything I want, but would prefer to order everything at once for a couple sets of pedals. I can probably only get away with buying parts fro two pedals at a time without my wife killing me, LOL. Sometimes I wonder how far can one go with making these hard to get parts yourself; being like a DIY version of unabomber Ted Kaczynski who made his own screws!

Joking aside, I wish more manufacturers made right angle PCB mount pots like Alpha's. How would you get the CTS ones that DOD uses anyway? Then again, that just adds another place's shipping charges which are probably more than the part cost.

[Steve Mavronis]

Half the time after asking a question it prompts me to figure out the answers. Could this be something like what I'm looking for in pots?

http://www.ctscorp.com/components/Datasheets/296.pdf



Scroll down to UM 296RE Molded Shaft, Shaft Perpendicular to P.C. Board. Have to make sure they have them on 100K audio and 500K reverse log. On this model the spacing of the standoff leg pins look closer together at about 0.15 inches apart vs 0.2 inches for the Alpha's. Still looking though. There are probably other brands out there with perpendicular to the board legs.

[petemoore]

Blackfire IIRC had such high gain the output wire was 'emitting' and the input wire was 'recieving', moving them to the outsides of the switch [led in the middle] seemed some help, but then Joe Davisson figured...put another stage so the output, inverted with the input broke the cross-feed.

[Alex C]

RG has written about this in the context of tube amps, but the same ideas apply for wiring in low-voltage stompboxes.

Crosstalk is picked up three ways: capacitively, inductively, and by shared resistance. Capactive pickup is maximized by wires close together and parallel, with high voltages on one wire and high sensitivity on the other. It is minimized by wires far apart, nonparallel or crossing at right angles, and by electrically grounded shielding between the wires.

http://www.geofex.com/article_folders/lead_dress/lead_dress_in_tube_amps.htm