a bit lost with a BD-2 perfboard layout

[eh la bas ma]

Hello,

I am looking to build my first circuit on stripboard ( on my board copper pads are only on 1 side, and they aren't connected to each other, so i guess it's called stripboard). Edit 2 : sorry, i was mistaken : it's a perfboard...

My favourite project would be a blues driver, because I don't know it yet,  it's a classic legendary circuit, and i do have 4x 2SK117 in my hands.

I figure that if I am going to build a circuit without a full kit, I'd like it to be really useful (and I would be proud !).

All I could find is a guitarfx layout for veroboard and I don't think it's the same (on vero, all pads are connected in lines, right ?)

http://tagboardeffects.blogspot.com/2013/03/boss-bd2-blues-driver.html

and i found this :

http://effectslayouts.blogspot.com/2017/01/boss-blues-driver-2.html



I guess this layout should work on stripboard perfboard, but I can't see where the pots are connected...

I read : 3 - Gain - 1 etc. but no pad directly indicated.

Any help and advice are welcome !

Edit : I think i got it, there is a stereo pot, an other pot next to the 4001 diode, and the last one around the top.

I wonder what is the yellow path ?

TL71 : Are there 3 pins (1, 5, 8 ) wich aren't connected to anything ?

[GGBB]

I think vero and stripboard are the same thing. When you have only pads - no connections - you have perfboard.

You can use a vero layout with perfboard - you just have to make the strip connections yourself. Usually that's done by extending one of the component leads to the others on the same strip and soldering them together.

For the effects layout - the pots are connected as follows:

[eh la bas ma]

Thanks !

I will correct my post accordingly.

[eh la bas ma]

I think i see a + sign in the other direction on the layout, but on the schematics i can see it's connected to R15.

https://lectric-fx.com/wp-content/uploads/2016/04/Bloozehound.pdf  (p.3, D-5)

Just to make sure, is the positive side of the 1uF cap oriented toward the 2k2 resistor ?

[iainpunk]

I think i see a + sign in the other direction on the layout, but on the schematics i can see it's connected to R15.

https://lectric-fx.com/wp-content/uploads/2016/04/Bloozehound.pdf  (p.3, D-5)

Just to make sure, is the positive side of the 1uF cap oriented toward the 2k2 resistor ?

yes, positive side towards circuit, negative towards ground

cheers

[GGBB]

Just to make sure, is the positive side of the 1uF cap oriented toward the 2k2 resistor ?

Yes. On the layout, it's the -ve side that's marked on the cap body as is the case with actual polarized aluminum electrolytic capacitors. So both the layout and the schematic are correct.

[eh la bas ma]

possible mod :

every components are soldered but the 1n4148 diodes. Before I do that, i would like to try the first part of this mod :

"D3 Change this 1SS133 to a different (1N4002) diode for asymmetrical clipping. This adds second order harmonics. This adds to the tube type sound. I like the sound of this change.

D7 D8 D9 and D10 Change 2 of of these diodes from 1SS133 to a single 1N4002. More second order harmonic distortion. Although the change is slight, I like it. We actually take out one of the two pairs and replace it with a single 1N4001."

from http://tagboardeffects.blogspot.com/2013/03/boss-bd2-blues-driver.html

I am thinking about a switch to have the option to choose between standard 1n4148 and the 1n4001.
But it isn't the same layout so i am confused.

Do you know where is D3 on the layout I am using ?

I can't find any 1n4001 right now, I have 1n5819 and 1n5817. Can I use one of these instead ?

If there is a real difference, I can go buy one 1n4001 tomorrow...

[eh la bas ma]

Is it me or this build is kind of hard ?

I never would have suspected this was going to be so long. I though it would take one afternoon... it's 03:00 am.

I' ve learned the value of a good old pcb now...I will appreciate them with a whole new light !

Some pics, it looks like there's been some maniac unleashed on a perfboard :






The good part was discovering Big Star, "Keep an Eye on the Sky" album, and Bauhaus while I was soldering. They're incredible bands, I love both.

Now pots , footswitch, jacks and  DC power jack and I'm good to put it to the test !

[eh la bas ma]

No success with the test.

Signal in bypass, that's all.

Before hunting for shorts and audio probing :

I have doubts about 2SK117 pinout and orientation. I tried to turn them around without success. I remember that I successfully used them in a Tweedman circuit by bending the middle legs to adjust the pads.

https://www.pedalpcb.com/docs/TweedMan.pdf



according to this, i should bend again the middle leg to adapt to the layout I guess ?

Also I'm using a switchboard from pedalpcb, but mine has no "BP" pad :



I wonder how should I wire the switch pad to connect a status led to the circuit ?

[duck_arse]

with the jfets we use, the source and the drain are the same thing, interchangable. so as long as you have the gate bent to the outside, it doesn't matter which other leg you call source, and which you call drain. so don't damage the part with mutiple bends.

and once you have the gate bent to end-pin, there is no reason to try the jfet fitting both ways, because only one way will be correct.

[eh la bas ma]

I think it's working ! Or close to do so, I'm not sure how this circuit behaves.

I managed to get all 2SK117 middle legs to go in the layout's Gate locations.

I do have a signal both in bypass and when the circuit is switched on.

All pots are responding, but there isn't any gain, unless i boost it by turning the guitar's volume up (active hambuckers pickups).
At unity on the instrument,  the Gain pot acts like a volume pot. When i do have some gain, fully CW, it's like a light overdrive and it cleans up quickly when I turn the pot CCW.

I couldn't find a stereo A250k, so I'm using a stereo A500k instead (I guess it should produce more gain, or is it the other way around ?). I also substitute the B10k tone pot with a B25k.

I wired the Gain pot with the top pads going to the upper terminals (closer to the enclosure when screwed onto it) and bottom pads to the pot's bottom terminals.

Maybe 2SK117 are quieter than J201 ?

An other explanation could be the diode switch : I didn't soldered on the board the top 1N4148 close to the TL71 ( above the one closest to the IC), and I soldered it on a switch, the negative side toward the switch terminal. I can't hear a difference in the gain texture when I switch to the 1N5817...

What could prevent this build from producing more gain ?

Edit : I am using a big 150n cap designed for high voltage (bottom of the first pic), I couldn't find a small one. I am not sure if it will behave exactly like the usual ones, in audio circuits...

[Kevin Mitchell]

I think vero and stripboard are the same thing. When you have only pads - no connections - you have perfboard.

Idk... I've seen single pad boards called vero, tag and perf. I tend to call them vero.
I've also seen strip boards called perf and vero.

Who makes up these rules? 

[eh la bas ma]

I boxed it to be able to use the controls easily.

I realized the gain pot is ok, it's only working in reverse.

Tone control acts like a volume control, that's the last and only issue now. Surely a short somewhere....

[eh la bas ma]

Allright !

Everything works perfectly now, and it sounds really good on first impressions.

Thank you for your help !

Looks like I've been lucky enough to build the circuit the right way on the first attempt, that's my biggest surprise.
I am so glad that I didn't have to use the audio probe...

I did scratch my head at some points, but that's the learning process I guess.

I strongly recommend this build : it's a bit longer than using a pcb, but if you like the building process you 'll have a fair amount of fun.

Can someone share some tips to build perfboard circuits in a much cleaner fashion than mine ?

For exemple, is it possible to start with the traces and connections, and then populate the board ?

[GGBB]

Can someone share some tips to build perfboard circuits in a much cleaner fashion than mine ?

I think yours looks pretty good for perfboard. I've only done two perfboard pedals - my first two builds. Those experiences drove me to learn how to etch, and etching drove me to learn how to use Eagle and order fabbed boards from China. My pedal building life is much more peaceful now .

The only tip I can offer - figure out which components will be the start, end, or corner of the "traces" and start with those so that you have the trace wire in place along the way when you solder the in-between connections.

[iainpunk]

i generally build the perf board as i would set up the schematic. when it involves an opamp, ill ''fold'' the circuit around the opamp. this makes recognising the circuit easier, especially when some time has elapsed since building the circuit, makes debugging and modification an easier process.

honestly, the BD-2 is a bit on the complex side for perf board builds. i build everything on perf so i tend to design quite minimised circuits, which are easier to put on perf boards.

another way of keeping it more oversee-able is dividing a circuit in sub circuits and separating them a bit on the board keeping the overview.

cheers

[duck_arse]

Allright !

Can someone share some tips to build perfboard circuits in a much cleaner fashion than mine ?

For exemple, is it possible to start with the traces and connections, and then populate the board ?

I have a method - I'll pm you for interest.