# The Protoboard Chronicles: The Replacement Fuzz



## Big Monk (Dec 15, 2021)

So, I can never leave well enough alone.

I went in to change the emitter cap on my hybrid Fuzz Face and all hell broke loose. Crazy ground hum, oscillation, etc. I had an issue with my instrument cable which confused the matter. In the end, I did not really feel like troubleshooting it. I have a few Universal Boards left so I thought I’d go Breadboard to Real Board.

I’m not 100% sure what I’m going for yet but I believe it will be a MK II/Supa with a Silicon Q1 and Q2 and Germanium Q3.


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## BuddytheReow (Dec 15, 2021)

What’s a universal board? Can you show a pic? Or is that a stripboard with breadboard-like copper tracks


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## Big Monk (Dec 15, 2021)

BuddytheReow said:


> What’s a universal board? Can you show a pic? Or is that a stripboard with breadboard-like copper tracks



This is the VanderScott Universal Fuzz Board:







It’s not completely universal. It will allow you to build either the Tonebender MK II, Marshall Supafuzz, Tonebender MK 1.5 or Fuzz Face. 

It allows for bias trimmers on all transistor slots, an output/Mids trimmer, base to collector caps on all transistor slots, and a base to power resistor for using Silicon transistors in Q1. There is also a Pre-Gain control. 

Technically you could do something along the lines of the Ramble FX Twin Bender as well. 

I have another iteration planned for this that will serve as the Fuzz 2022 giveaway or “The Fuzz”. 

This revision will add slots for emitter resistors on all three transistors, the option to put the input cap before or after the Pre-Gain, a dedicated slot for a cap across the feedback resistor and a few extra components slots for configuring Q1 as a unity gain buffer with adjustable series resistance on the output to the 2nd stage. 

I had originally planned on doing 2 more Universal Boards, 1 for the Tonebender MK I types and 1 for the Tonebender MK III types. I still might do that.


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## Big Monk (Dec 15, 2021)

So I had a chance to do a bit or Protoboard if tonight. 

I decided to redo the Hybrid Fuzz Face with a few changes:

1.) Make the Q1 bias fixed. 36k locked the collector voltage in at around 1.08 vDC, which is where I had it set. 

2.) Tweak the volume pot down to 100k to brighten things up a touch. 

3.) Tweak the emitter cap down to 10 uf and keep the input cap down to 0.82 or 1 uf. Not sure yet. It was at 1 uf and I might keep it that way until I see how the rest of the circuit plays out. 

4.) Put in a a larger output/Mids trimmer. 470 ohm and 1k combo. 

5.) Go for a larger sweep on Q2 bias trimmer. 3 vDC-8.2 vDC depending o. The position of the output/Mids trimmer. 

I dialed in the bias voltages tonight and I am traveling to pick up my in-laws at the Albany Airport tomorrow so I probably won’t solder this up until Friday. I need some time to determine feedback bypass, Q1 and Q2 base to collector caps if they are needed. 





Transistor set is an Amperex A115 (hFE = 86) for Q1 and a General Electric 2N169 (hFE = 120) for Q2. 

I have 2 boards left and an old Ball Silver enclosure so I maybe throw a full Hybrid MK II together as well. 

These are the last 2 Rev. 3 boards I have left and then I’ll make the tweaks for “The Fuzz” or Rev. 4.


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## BuddytheReow (Dec 16, 2021)

Do you tend to keep your indicator LED fixed to your board for other builds? Same question but with the power supply jumpers for both boards. Looks great so far!


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## Big Monk (Dec 16, 2021)

BuddytheReow said:


> Do you tend to keep your indicator LED fixed to your board for other builds? Same question but with the power supply jumpers for both boards. Looks great so far!



The green is a power indicator. The red is the bypass LED for the circuit. 

Yup. I keep all the jumpers in. Also, I have a trim pot between power in and the actual power rail to adjust voltage down on my Snark adapter.


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## finebyfine (Dec 16, 2021)

Have you thought about doing a ground plane copper pour or are you specifically avoiding it? Defaulting to them on my boards has had a big noticeable reduction in hum and stray noise for me.


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## Big Monk (Dec 16, 2021)

finebyfine said:


> Have you thought about doing a ground plane copper pour or are you specifically avoiding it? Defaulting to them on my boards has had a big noticeable reduction in hum and stray noise for me.



Frankly, I’m a neophyte when it comes to PCB design. This was originally a proof of concept that I could even make a functional PCB and that has proved fruitful. 

I’m not avoiding it I just have very little practical experience with it!

I’d welcome any tips and I’m always looking to keep noise and hum down. I use DipTrace.


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## finebyfine (Dec 16, 2021)

Big Monk said:


> Frankly, I’m a neophyte when it comes to PCB design. This was originally a proof of concept that I could even make a functional PCB and that has proved fruitful.
> 
> I’m not avoiding it I just have very little practical experience with it!
> 
> I’d welcome any tips and I’m always looking to keep noise and hum down. I use DipTrace.



I have only started using them very recently, and only even more recently have become close to happy with some of my pcbs. @Chuck D. Bones laid out a great bullet list that helped me immensely: https://forum.pedalpcb.com/threads/pcb-layout-guidance.8843/post-81358 I went from basically botching every attempt at making an effect pcb to having 3 or 4 that I am content with since digging into everything in that list.

I can post how to do a ground plane fill for a 2 layer pcb when I have the time in an hour or two today but it's very easy in diptrace.

Edit:

I'd be surprised if there are parts of how I'm explaining doing this that can't be done better but I just wanted to give a rough idea. This is also just specifically a ground pour fill.

Basic ground pour fill​Let's assume this board is entirely routed, with the exception of our ground net. The ratlines here are that net. Blue is top, red is bottom.





(For the sake of easier routing, I'll hide the ground net's ratlines until the rest is routed, which can be done in the Design Manager's Nets panel)





Then we use the tool. We'll use it on both the bottom and top layers, but I'll be walking through doing the top layer before the bottom.
We're gonna snap it to the board outline after it's placed so I just quickly do it oversize of the board





For the fill options:

In the `Pouring` tab, check `Use Net Clearance`.
I'll leave other parts of this tab unchanged for now to show why the settings become important.

In `Connectivity` a few things:
`Connect to Net` set to your ground net
`Hide Net Ratlines` to `Automatically`.

Under `Border`:
Check `Depending on Board`
Check `Snap to Board Outline`

I've dimmed the blue of the top layer to show here why *not* to `Hide All Net Ratlines`. Despite being poured, the ground net is broken and the top left corner pad does not make a connection to the bottom pad of 2M, and the bottom pad of the 3K3 does not connect to the bottom right ground pad. You can also confirm this under `Verification -> Check Net Connectivity`. Using `Hide All net ratlines` can make you forget that a pour fill does not always route the entire net if there are gaps, which is a fun thing to only realize once you're holding a board in hand.





Once we repeat this for the bottom layer, the Ground net might become unbroken without changing anything else - although in this case it did not fix this.

I'll do a combination of a few things at this point:

Double check non ground routing and component placement to see if there's an easy way to fix the breaks
In this example, they were fixed completely after I realized that the outer pads don't need to be this large for the component

I prefer the above but worst case scenario:
I'll incrementally creep down the `Line Width` and `Line Spacing` in the `Pouring` tab a bit
I'll also change the `Border Clearance`, or alternatively make the board itself larger.
I don't recall the values off the top of my head but it isn't hard to find suggestions for safe values for these.

I've only had a ground pour fill not automatically grab all of the grounds once before I sent off my pcb, but understanding how it can fuck up is knowing how to avoid it. There are tutorials out there that go more in depth that are worth reading, to reiterate this is just a rough cover.


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## Big Monk (Dec 16, 2021)

finebyfine said:


> I have only started using them very recently, and only even more recently have become close to happy with some of my pcbs. @Chuck D. Bones laid out a great bullet list that helped me immensely: https://forum.pedalpcb.com/threads/pcb-layout-guidance.8843/post-81358 I went from basically botching every attempt at making an effect pcb to having 3 or 4 that I am content with since digging into everything in that list.
> 
> I can post how to do a ground plane fill for a 2 layer pcb when I have the time in an hour or two today but it's very easy in diptrace.
> 
> ...



This is great stuff.

Is there a way to do this for manual routing of a board? I don’t currently use both sides and I route everything manually.

You are WAY ahead of my PCB abilities for sure.


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## Big Monk (Dec 16, 2021)

I was able to play this for a few minutes today:





As expected, had some noise that was part being on the Protoboard and also just standard Fuzz pedal circuit noise. 

I tried to remember the sleep deprived days of my EE undergrad studies and my knowledge of high and low pass filters. 

We know the Tonebender MK II uses a cap to ground on the input to roll off highs. I thought that maybe it would also help when combined with my pre gain control to form a high pass filter for eliminating some circuit noise and RF as well. 

I subbed in a 2200pf and it worked very well. Still some residual noise but no RF that I could hear at lower volumes. I can try and handle the leftover noise at other points. The good news is that this cap does not seem to affect the treble response but really squashed the noise. 

I started with a 1 uf input cap and 10 uf emitter cap. It was a touch mushy at lower volumes so I tweaked down to 0.68 uf for the input and 6.8 uf on the emitter cap and full volume testing will tell me where to go from here.


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## fig (Dec 16, 2021)

Just curious as to why you aren't using the terminal blocks instead of shoving those pots in your breadboard?


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## Big Monk (Dec 16, 2021)

fig said:


> Just curious as to why you aren't using the terminal blocks instead of shoving those pots in your breadboard?



When I bought the parts for it I mistakenly purchased 2 terminal blocks instead of 3 terminal. I did not have 3 terminal 45 degree blocks but did have 90 degree 3 terminal blocks. 

The 90 degree blocks are a pain in the ass to use. 

I need to order 6 45 degree term blocks. Until them, I’m using pots on the boards themselves.


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## fig (Dec 16, 2021)

Coming your way...


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## Big Monk (Dec 16, 2021)

fig said:


> Coming your way...



Oh jeez! 

The most charitable builder on the forum! 

Now I’ll just have to carefully remove the others! 

I’ll make sure your copy of “The Fuzz” is extra special.


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## BuddytheReow (Dec 16, 2021)

@fig i always wonder how much of your stock is giveaways and how much you use. You are very generous


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## fig (Dec 16, 2021)

There are some extremely kind and generous members ( and owner ). I could not possibly give back as much as I've received. 😘


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## Big Monk (Dec 16, 2021)

fig said:


> There are some extremely kind and generous members ( and owner ). I could not possibly give back as much as I've received. 😘



Somebody put that on a T-Shirt. Quote of the year!


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## Harry Klippton (Dec 16, 2021)

I went to the pedalpcb forum and all I got was this lousy headache


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## Big Monk (Dec 16, 2021)

finebyfine said:


> I have only started using them very recently, and only even more recently have become close to happy with some of my pcbs. @Chuck D. Bones laid out a great bullet list that helped me immensely: https://forum.pedalpcb.com/threads/pcb-layout-guidance.8843/post-81358 I went from basically botching every attempt at making an effect pcb to having 3 or 4 that I am content with since digging into everything in that list.
> 
> I can post how to do a ground plane fill for a 2 layer pcb when I have the time in an hour or two today but it's very easy in diptrace.
> 
> ...



I think there is enough info here for me to do a ground pour even with my simple manual one sided approach.


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## finebyfine (Dec 16, 2021)

Big Monk said:


> I think there is enough info here for me to do a ground pour even with my simple manual one sided approach.


Lemme zoom back out and talk about the advantage of them too. Should have done that first probably lol

It allows you to prioritize routing signal traces as short as possible by removing the most cumbersome net trace from the routing process
The larger ground surface (compared to a regular track) has lower impedance, which means that there’s less impact and chance of noise from voltage differences across ground from active components
The pour around signal traces effectively does the job of a shielded wire, reducing crosstalk between parallel signal paths


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## Big Monk (Dec 16, 2021)

finebyfine said:


> Lemme zoom back out and talk about the advantage of them too. Should have done that first probably lol
> 
> It allows you to prioritize routing signal traces as short as possible by removing the most cumbersome net trace from the routing process
> The larger ground surface (compared to a regular track) has lower impedance, which means that there’s less impact and chance of noise from voltage differences across ground from active components
> The pour around signal traces effectively does the job of a shielded wire, reducing crosstalk between parallel signal paths



And is the concept of the pour applicable for someone like me not using the typical schematic to PCB conversion in these programs?

I typically do rough drafts of layouts in DIYLC and then single side manual routes in DipTrace.


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## Big Monk (Dec 17, 2021)

Figured it out using the instructions from @finebyfine!


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## fig (Dec 17, 2021)

boo-yah! Looks good Derek.


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## Big Monk (Dec 17, 2021)

Since I'm single sided, I'm thinking the ground pour should only be on the bottom.


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## fig (Dec 17, 2021)

Big Monk said:


> Since I'm single sided


There are groups for this...🧐


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## Big Monk (Dec 17, 2021)

Some white sock noodling on what I have so far. This has a real edge to it which is nice but I need to reclaim so oomph and note bloom for feedback tones. Might try bumping the emitter cap back up to 10 uf. The Q2 bias pot has a subtle but noticeable, and broad, sweep to it:


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## Username123 (Dec 17, 2021)

Big Monk said:


> Some white sock noodling on what I have so far. This has a real edge to it which is nice but I need to reclaim so oomph and note bloom for feedback tones. Might try bumping the emitter cap back up to 10 uf. The Q2 bias pot has a subtle but noticeable, and broad, sweep to it:


My favorite part was when it went wahwahwaaaaahwahwahwahwahwahwah.


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## Big Monk (Dec 17, 2021)

Username123 said:


> My favorite part was when it went wahwahwaaaaahwahwahwahwahwahwah.



The modified PedalPCB buffer did the trick!


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## Username123 (Dec 18, 2021)

Big Monk said:


> The modified PedalPCB buffer did the trick!


Interesting. Might have to take a look at your thread about that. My 1990s crybaby is being a little weird in bypass. I might just take the whole board out and put a tearjerker board in, as it sounds kinda crappy for whatever reason. The person who gifted it to me also replaced the pot on it without choosing the same value, so that could also be a problem.


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## Big Monk (Dec 19, 2021)

So, worked on this today and came up with the following:







Full volume tests tomorrow.


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## benny_profane (Dec 19, 2021)

Those poor jacks.


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## Big Monk (Dec 19, 2021)

benny_profane said:


> Those poor jacks.



They were pulls from other projects. I’m short on jacks until my next Tayda order. 

This is really a prototype for the Fuzz 2022 giveaway.


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## Big Monk (Dec 22, 2021)

A few things:

1.) Thanks to @finebyfine for the crash course in ground fills!

2.) Thanks to @PedalPCB for giving me the inspiration to even want to do my own boards

3.) Thanks to the good natured ball-busting of @Harry Klippton and @thewintersoldier and @thesmokingman and @Stickman393 for helping me try and step my game up at all

4.) Special thanks to @thewintersoldier for getting me back to basics and what makes a circuit tick rather than letting me reinvent the Fuzz Factory

5.) Thanks to @fig for being an all-around great guy and for instilling a spirit of contests and giveaways here. 

I’ve decided to break up my Universal Board idea. When I went to revise it, it was just too busy, with added jumpers and just not enough real estate to house my revised I/O scheme. 

So I’ve decided to call these new board the Enhanced series. Classic circuits with small enhancements. First up is the Enhanced Fuzz Face, the basis for “The Fuzz”, which is the Fuzz 2022 giveaway circuit:







It has a few tweaks on the classic circuit:

1.) The simple control set of Fuzz and Volume is expanded to include a Pre-Gain, which I’ve included on all my fuzzes. 

2.) There is a slot for a series resistor off the output of the Pre-Gain. This does 2 things: It makes it so that when Pre-Gain is full up, there is a small targeted resistance to kill hum and other noise and it interacts with:

3.) The cap from base to ground of Q1. This is a trick borrowed from the MK II Tonebender. Here it is MUCH smaller than on the MK II, as we simply want it to form a high pass filter with the series fixed resistor off of the Pre-Gain. It can be set to not mess with the treble content of the pedal and simply filter out RF and other noise. 

4.) Dedicated slots for B-C caps on both transistors, if needed. 

5.) Dedicated a lot for a feedback bypass cap. With a higher gain Fuzz Face, this is critical for squelching noise and oscillation. 

6.) Q2 has a bias trimmer and an output/Mids trimmer. 

7.) Dedicated slot for a resistor in series with the wiper of the Fuzz pot and the emitter cap. Another way to limit the max range of the pot and mimic the “Turn the fuzz control down” method of eliminating fizziness and noise in higher gain units. 

8.) Lastly, parallel slots for emitter caps. Sometimes you want more than 6.8 uf and less than 10 uf or you simply want something like 15 uf from modern values.


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## finebyfine (Dec 22, 2021)

Awesome job @Big Monk. Really cool to see this come together and I hope you're as proud of it as you should be! 

I think you've struck a really nice balance in terms of customizability without throwing the kitchen sink at it, or making it an 8 knob fuzz. Several of the options you've added are ones I've wished were on some boards, and the others that I never would have thought of all sound super useful. 

I'd love to buy one once you get them in!


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## Big Monk (Dec 22, 2021)

finebyfine said:


> Awesome job @Big Monk. Really cool to see this come together and I hope you're as proud of it as you should be!
> 
> I think you've struck a really nice balance in terms of customizability without throwing the kitchen sink at it, or making it an 8 knob fuzz. Several of the options you've added are ones I've wished were on some boards, and the others that I never would have thought of all sound super useful.
> 
> I'd love to buy one once you get them in!



I’m going to use the same concept for MK II/Supa boards, Rangemaster, Tonebender MK I, MK III, etc. Enhanced versions of the classics. 

You don’t have to buy one. I’ll give you one!


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## fig (Dec 22, 2021)

Great work sir. I _really _like these revisions!


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## Paradox916 (Dec 22, 2021)

Very cool,  I know you have been working on this for a bit, are you planning on any sound samples in the near future? I have some of those 🎩 GE transistors, I don’t remember where they came form( probably small bear a while ago)  or why I even got them.  And I’m not even sure what to build with them( a fuzz of course.)


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## Big Monk (Dec 22, 2021)

Paradox916 said:


> Very cool,  I know you have been working on this for a bit, are you planning on any sound samples in the near future? I have some of those 🎩 GE transistors, I don’t remember where they came form( probably small bear a while ago)  or why I even got them.  And I’m not even sure what to build with them( a fuzz of course.)



I’m gonna put in an order this week for about 20 boards.

My plan is to make a prototype with sockets for most parts that would have to change for different transistors. Then I’ll put a unit together and post clips.

I’m not sure I can do the hybrid for the giveaway. The GE 2N169s I have left are a personal stash and I’m not sure I can swing buying the 36 or so I’d need to sort and spec for the Q2 gain range.

So “The Fuzz” may end up being all silicon. That will allow me to stock up on some desirable units from SBE and work with the giveaway winners to tweak the circuit to their liking.

This is pretty close to how my personal hybrid sounds right now, although this was built on a leftover V3 board.


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## Big Monk (Dec 22, 2021)

Last changes.

I was putting together a rough draft of the Enhanced MK II boards with emitter resistors. I realized that since Silicon MK II unitscan bebuilt with run of the mill modern silicons using emitter resistors to drop the gain, that this would be useful for the Enhanced Fuzz Face boards as well.

If not used, you can just put 0 ohm jumper resistors in or simple jumpers.







I need to so a quality check on these and then i'm ordering 20.


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## mdc (Dec 22, 2021)

If you've not watched the Effects Layouts youtube videos on PCB layout/eagleCAD/etc you should check them out. I'm not sure how similar diptrace and eaglecad are, but a lot of the principles will undoubtedly carry over.


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## Big Monk (Dec 22, 2021)

mdc said:


> If you've not watched the Effects Layouts youtube videos on PCB layout/eagleCAD/etc you should check them out. I'm not sure how similar diptrace and eaglecad are, but a lot of the principles will undoubtedly carry over.



Welp, your post made me go into DipTrace and finally try a 2 Sided design. Pretty sweet stuff.


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## mdc (Dec 22, 2021)

It's a fun jigsaw puzzle.


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## Big Monk (Dec 22, 2021)

mdc said:


> It's a fun jigsaw puzzle.



I did a “Save As” with my completed design and then shrunk it a bit by moving the I/O to the top and move some troublesome connections to the top. 

I may start from scratch with 2 sides in mind and see what I can do.


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## Bricksnbeatles (Dec 22, 2021)

Any reason you don’t have any thermal relief for the grounded pot pins?


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## Big Monk (Dec 22, 2021)

Bricksnbeatles said:


> Any reason you don’t have any thermal relief for the grounded pot pins?



I’m not gonna lie: I have no idea what you mean!

EDIT: The understand what you mean now. Honestly, I hadn’t thought of it because this will be the first board I’ve made using a copper pour. I’ll incorporate the thermal relief before finalizing!


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## Big Monk (Dec 23, 2021)

@Bricksnbeatles 

Went back in this morning and deleted the copper pour then re-poured with 4 spoke thermal relief!

Good catch and thanks for the tip!


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## Big Monk (Dec 23, 2021)

So, revised layouts. Added ground pours on both sides with thermal relief:


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