Alternative PCB for Pythagoras circuit at PCBWay.com

Paul.Ruby

Paul.Ruby

Well-known member
I screwed up the thread title. Meant to say "... at PCBWay.com"

In order to embed reverb into a combo pedal, I've made a PCB in small format. My intent is to install an always-on reverb into a combo pedal and use trim pots to "set it and forget it." Here's one with alpha pots used for testing. It's almost identical to the Pythagoras with some minor exceptions. The LED is hooked to the clipping indicator from the FV-1. The output capacitor is increased to 2.2uf as I was getting some low end loss. I used SMD chips since I had to solder the FV-1 anyway. Easy to do on a hot plate with some solder paste on the pads.
P1020331.JPG

Eeprom and jumpers on the back for easy access. (I know the flux needs some clean up.)
P1020332.JPG
Interactive BOM:

PCBWay link to the project (might not be live yet). I have a few left if anyone wants a PCB in the US. I will likely only use 5 of the 10 ordered. There is a BOM at this link as well with mouser links to all the parts. The links to POTs point to 12-turn trimmer pots that will fit but the footprint is for alpha 9mm vertical pots.
www.pcbway.com

Spin FV-1 Embedded Project Board - Share Project - PCBWay

This is a smaller version of the Pythagoras from PedalPCB.com for creating Reverb, Delay, Flange or Chorus effects. The intent is to make it as small as possible for embedding into a combo-pedal forma...
www.pcbway.com
 
FYI... The board is 2.5x1.75". I squeezed the one above into a 1590G but it was very tight on the sides to fit the jacks and I had to cut a hole in the base plate for the jumpers and eeprom to stick through a bit (but it gives me access to them easily). This case is only 1" tall. If you leave out the eeprom and jumpers to just pick an internal program then it fits fine in the 1" height. The 1590G2 is 1.3" tall, which would be better and it's probably the smallest case that can be used for a stand-alone unit with the jumpers and eeprom on the back.

Of course, the real purpose of this is as one module in a larger combo pedal case like I've done here:

Combo build for pedal board core: Pre-boost, Clean/drive channel, cabsim, noise-gate, post boost.

I've spent an inordinate amount of time creating a combo build with 3 footswitches in a 1590DD case. The picture tells most of the story. I'm happy to share info about it if anyone is interested... I'm wondering if anyone else has any interest in such a thing.... To make this all fit, I had to...
forum.pedalpcb.com forum.pedalpcb.com
 
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Had to make some tweaks to mine for signal levels. The clipping LED was on all the time, so signal was too hot into the FV-1. And then the signal out of the FV1 was hot and hard to only add a small amount of reverb. These changes might be needed for others. First get input signal adjusted to avoid hard clipping. Then further reduce output signal if it's still too hot to mix into the output signal.
1719939663777.png
 
I just found this little coded rotary switch on mouser and ordered some. Also tweaked my PCB design to use it and need an excuse to order a batch. Is anyone interested? I've already built enough of the original boards that I don't need them with a rotary. But, it's so cheap to order 10...

UPDATE: I must have a serious problem... Ordered 10 PCBs from PCBWay... And 10 more FV1. I need counseling. :)

Another UPDATE. The correct rotary for pythagoras is this one (the "real code" version) but I ordered the "complementary code" version above. So, mine are going to have the numbering reversed. 0 will be 7, 1 will be 6, etc... Duh.
 
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Paul.Ruby said:
Konu başlığını yanlış yazmışım. "... at PCBWay.com" demek istemiştim.

Bir kombo pedala yankı eklemek için küçük boyutlu bir PCB yaptım. Amacım, kombo pedala sürekli açık bir yankı yerleştirmek ve "ayarlayıp unut" özelliği için trim potansiyometreleri kullanmak. İşte test için alfa potansiyometreleri kullanılan bir tane. Bazı küçük istisnalar dışında Pisagor ile neredeyse aynı. LED, FV-1'in kırpma göstergesine bağlı. Düşük uçta biraz kayıp yaşadığım için çıkış kapasitörü 2,2 uf'a yükseltildi. FV-1'i zaten lehimlemem gerektiği için SMD çipleri kullandım. Pedlere biraz lehim macunu sürüp, sıcak bir plaka üzerinde kolayca yapılabilir.
View attachment 77764

Arkada kolay erişim için eeprom ve jumper'lar var. (Flux'un biraz temizliğe ihtiyacı olduğunu biliyorum.)
View attachment 77765
Etkileşimli BOM:

Projenin PCBWay bağlantısı (henüz yayında olmayabilir). ABD'de PCB isteyen olursa elimde birkaç tane kaldı. Sipariş edilen 10 adetten muhtemelen sadece 5'ini kullanacağım. Bu bağlantıda, tüm parçaların fareyle erişilebilen bağlantılarını içeren bir malzeme listesi de mevcut. POT bağlantıları, sığacak 12 turlu trimmer potansiyometrelere işaret ediyor, ancak kapladığı alan alfa 9 mm dikey potansiyometreler için.
www.pcbway.com

Spin FV-1 Embedded Project Board - Share Project - PCBWay

This is a smaller version of the Pythagoras from PedalPCB.com for creating Reverb, Delay, Flange or Chorus effects. The intent is to make it as small as possible for embedding into a combo-pedal forma...
www.pcbway.com
Click to expand...
Hi, Paul. I have a question. What are the exact pinouts on the back of the board, just above the eeprom? Do I need to use a rotary switch to correspond to each pin? So, do we add a rotary switch to the pinouts there? Also, is your circuit designed to read 8 effects? Best regards.
 
I'll attach each of the pins I've marked with red lines to the pins of the 8 DPT rotary switch, so that they correspond to the same pins. Is this correct? So, these pins are the keys that can select programs? I'm a bit new to this, so excuse me.
 

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serhay said:
I'll attach each of the pins I've marked with red lines to the pins of the 8 DPT rotary switch, so that they correspond to the same pins. Is this correct? So, these pins are the keys that can select programs? I'm a bit new to this, so excuse me.
Click to expand...
Those are for jumpers to choose what gets connected, side to side. All the signals (T0, S0, S1, S2) are pulled down to ground with a resistor on the board. Adding a jumper to each will connect them to Vcc. Here's the relevant part of the schematic. You can use a "real-code" rotary encoder with the common pin connected to Vcc. But, this PCB is meant for a jumper-header, so you will need to run wires from there to a rotary encoder. The T0 signal. left unjumpered, tells the FV-1 to use the internal EEPROM. A jumper on T0 tell sit to use an external EEPPROM. S0,S1,S2 would go to the rotart encoder.
1757813215429.png
 

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Paul.Ruby said:
Those are for jumpers to choose what gets connected, side to side. All the signals (T0, S0, S1, S2) are pulled down to ground with a resistor on the board. Adding a jumper to each will connect them to Vcc. Here's the relevant part of the schematic. You can use a "real-code" rotary encoder with the common pin connected to Vcc. But, this PCB is meant for a jumper-header, so you will need to run wires from there to a rotary encoder. The T0 signal. left unjumpered, tells the FV-1 to use the internal EEPROM. A jumper on T0 tell sit to use an external EEPPROM. S0,S1,S2 would go to the rotart encoder.
1757813240420.png
Click to expand...
I should add, you cannot use an "8PDT" rotary. It must be a "Real code rotary encoder" which will have 4 pins: Common, 0, 1, 2. Common goes to Vcc, which is all on one side of the jumper header and then S0, S1, S2 to the 0, 1, 2 pins on the encoder. This switch at mouser is an example of such a thing:
 
Paul.Ruby said:
I should add, you cannot use an "8PDT" rotary. It must be a "Real code rotary encoder" which will have 4 pins: Common, 0, 1, 2. Common goes to Vcc, which is all on one side of the jumper header and then S0, S1, S2 to the 0, 1, 2 pins on the encoder. This switch at mouser is an example of such a thing:
Click to expand...
So, to which pin numbers exactly should I connect the rotary switch used to select the 8 programs?
 
serhay said:
So, to which pin numbers exactly should I connect the rotary switch used to select the 8 programs?
Click to expand...
Here's a view of the bottom of the PCB where the eeprom and jumpers are. All the pads on the right side are VCC. Any one of those goes to the common on the rotary encoder. The pads on the left are the individual signals. S0, S1 and S2 go to the other three pins on the rotary encoder.
1757866152806.png
 
Paul.Ruby said:
Here's a view of the bottom of the PCB where the eeprom and jumpers are. All the pads on the right side are VCC. Any one of those goes to the common on the rotary encoder. The pads on the left are the individual signals. S0, S1 and S2 go to the other three pins on the rotary encoder.
View attachment 102901
Click to expand...
So, what I'm trying to explain is which pins on your schematic should I connect the eight program modes I can select to the pins of the rotary switch? How many pins does this rotary switch have? What kind of rotary switch should it be? My other question is, which pins are the transition pins between the eeprom and FV-1, and how do I connect a rotary switch or switch to these pins? I hope I've made myself clear. I ordered your boards from PCBway.
 
serhay said:
So, what I'm trying to explain is which pins on your schematic should I connect the eight program modes I can select to the pins of the rotary switch? How many pins does this rotary switch have? What kind of rotary switch should it be? My other question is, which pins are the transition pins between the eeprom and FV-1, and how do I connect a rotary switch or switch to these pins? I hope I've made myself clear. I ordered your boards from PCBway.
Click to expand...
No. There isn't a direct mapping to such a switch. Use a rotary encoder.
 
Yes, I looked at the datasheet and now I understand everything better. I'm a bit new to digital. Please excuse me. Thanks to you, I completely understood and solved the project. If you have any video demos of your card's effects, I'd love to hear them. Thanks again for everything, Paul.
 
Paul.Ruby said:
There is a 4th pin, the common pin. Look at the datasheet.
Click to expand...
I can't find a rotary encoder in my country. Actually, it would be great to use this switch, but I will go for a normal rotary switch. If we change your schematic like in the picture and add the diodes, I think we can use a normal rotary switch, there will be no problem, is that correct? Paul.
 

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serhay said:
I can't find a rotary encoder in my country. Actually, it would be great to use this switch, but I will go for a normal rotary switch. If we change your schematic like in the picture and add the diodes, I think we can use a normal rotary switch, there will be no problem, is that correct? Paul.
Click to expand...
yes
 
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