Building a Black Eye : tubes daughter boards mistake, is it really bad ?

[vigilante398]

I added a jumper between the two uncircled pads : the volume and the signal strength has been restored ! Hurrah !

On the musical side, now the effect sounds fully working, and ready to be put to good use.

However, i can't find the short between pin 4 and 5 (dark blue). I moved the tip of my iron all around the dark blue connector pad on the daughterboard and on the main pcb, but it's still ringing. Visual inspection didn't help neither, i can't see anything suspicious.

Even if i remove the tube from the socket, these two socket pads are still ringing.

I checked the other tube daughterboard at pin 4 and 5 and i also have continuity there.

If pin 4 and 5 shouldn't be connected together, which one shouldn't be connected to the dark blue connector pad ? And to which connector pad should it be connected instead ?

Voltage at UF4007 negative side is still at 162V instead of 240V.


Just to be clear, these continuity tests have been performed on the soldering side, the tube is located on the other side of the pcb. In the left picture with colored circles, we are looking at the soldering side of the daughterboard. The tube socket is set on the other side, with a white circle instead of a Sushi logo :
View attachment 63663View attachment 63669


Pin 9 is the purple socket pad, above the "i" of the Sushi logo ? On my build it's ringing with the purple connector pad, i checked the other daughterboard and it also rings with the same corresponding pad. I can also see a trace on the pcb between these two points.

If i am being confused with the daughterboard's orientation, and pin 9 is the light blue socket pad (above the "S" of the logo), i also have the same connection with the same corresponding connector pad on the other daughterboard.

If pin 9, most probably the light blue one, isn't supposed to be connected to anything, there should be no trace going to that socket pad... I can't see where and how there could be a short if that socket pad is on its own, disconnected from the whole circuit...

At least, now the effect sounds really good, with more than enough volume on tap. I wonder if it's safe to play with it, despite the pin 9 and pin 4 and 5 situation ?

From a musical point of view, it looks like the jumper alone solved everything...I am really tempted to leave it alone now that everything works.
Could it blow off, electrocute me, or damage the tube because of pins 4, 5 and 9 ?

If it works then it works, I wouldn't worry about it. But pin 9 of the tube socket should not be connected to anything. The only reason it would show up as being connected is if you still have the tube in the socket. The tube's filaments (pins 4, 5, and 9) are essentially a pair of low-value resistors and will show up as connected if you're just probing for continuity. You can't accurately measure which pad connects to which unless you remove the tube from the socket.

 

[jhaneyzz]

I had low voltage on one of my Sushibox builds that was resolved when I really flowed the solder more heavily on the tube socket pins.

 

[eh là bas ma]

I received the new pcb set yesterday. I spent half of the night desoldering the damaged tube daughterboard, and the tube socket. Then i replaced it and managed to do a reasonably clean job with the connectors. I thought it was worth trying to change only this suspicious tube pcb, before desoldering everything and change the main board with both daughterboards.

This morning it sounds like it finally works, lots of gain and volume on tap, tone control is perfectly working, i can hear some beautiful distorted sounds.
I will post a sound sample tomorow or later today, to have confirmation.

At UF4007 negative side, this time the meter reads 220V at first, but it slowly goes down to 172 V.

 

[eh là bas ma]

Here is a sound sample. I think it sounds great but i just want to make sure everything is working as expected :

Volume set around 1/4 of rotation, Tone set a bit passed middle of rotation, Gain in the beginning of the recording, set at 1/4, and increased progressively, until fully CW at the end of the sample.

https://soundcloud.com/ehlabas-ma-chaussure%2Fblack-eye-test-2wav

I hope this time everything's all right ?

 

[eh là bas ma]

I am very impressed with the Black Eye, i am glad i didn't give up on this project ! My build will be put to good use.

Just one final question : do you think this circuit would be a good match for an extra relay bypass ?

I have a TH Custom's relay bypass kit, i guess i can manage to find some room inside the Black Eye enclosure, but i wonder if there could be any downside ?

https://diy.thcustom.com/?wpdmdl=3234

If you think it's compatible, can you please tell me what are the breakout board pad's designations, so that i can replace the original 3PDT with a new one, connected to TH Custom's relay bypass pcb ?

 

[vigilante398]

If you can find a place to put it I don't see any reason it wouldn't work.

Switch pinout is, from left to right:

Input jack - Effect input - Ground - LED cathode - Effect output - Output jack

 

[eh là bas ma]

Thank you very much !

It's working, but i still have the same level of noise upon activation, nothing too annoying, but still quite noticeable. I thought a relay bypass with a momentary footswitch would make it totally silent, but no... The relay bypass is completely useless.

Maybe it's the leds, i connected the cathode pad from the Black Eye pcb to the cathode pad on the relay pcb (where i left the led resistor R2 empty), leds are both still slightly lit when the effect is switched off. They are brighter when switched on. I'll try without leds, see if that's where the noise comes from....