Bastl Spa expander for GrandPa, DIY help

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khyber
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Bastl Spa expander for GrandPa, DIY help

Post by khyber » Fri Jan 10, 2020 10:56 am

I built a Spa kit recently to hook up to my GrandPa, but the module does not seem to work properly. I'm a little embarrassed by this as there are so few parts to the kit, I'm positive there are no traces that are touching and I've reflowed solder to all the joins, but no such luck in getting the module to work.

I have the module hooked up to the GrandPa via the 6 pin connection cable and I also have a power cable hooked up to the back of the expander (as well as the GrandPa). I've check the 3 ICs and they all seem to be seated properly and all the pins are plugged in.

The issue I'm having is that the Spa does not seem to affect the GrandPa at all, I turn the knobs and nothing changes about the sample I'm triggering. I hear a faint clicking sound as I turn the knobs as well. CV jacks do the same thing, only hear a clicking sound as voltages modulate the signal at the jacks, but nothing changes on the sample itself.

Here's a video I made to demonstrate the issue: https://wetransfer.com/downloads/81c13c ... 015/e3f0cf

I've emailed Bastl to see if they can help but I'm still waiting to hear back, figured I'd reach out on Muffs to see if anyone has run into this issue with the Spa build as well.

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brawnywynn
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Re: Bastl Spa expander for GrandPa, DIY help

Post by brawnywynn » Sat Jan 11, 2020 12:55 pm

Hi, I built one of these that works.

Can you post pics of the tops and bottoms of each pcb
And a pic of the module as you have it connected to the grandpa?

Thanks!

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khyber
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Re: Bastl Spa expander for GrandPa, DIY help

Post by khyber » Sun Jan 12, 2020 9:12 am

brawnywynn wrote:
Sat Jan 11, 2020 12:55 pm
Hi, I built one of these that works.

Can you post pics of the tops and bottoms of each pcb
And a pic of the module as you have it connected to the grandpa?

Thanks!
Sure here you go:

This was after I touched up all the solder points, haven't cleaned up the board yet but hope these pictures help

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brawnywynn
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Re: Bastl Spa expander for GrandPa, DIY help

Post by brawnywynn » Mon Jan 13, 2020 9:26 pm

It looks pretty good to me. I'd clean up the boards and see whether that improves the situation.

Not sure the best way to check whether the chips are functioning correctly, obviously if you have any dupes that you know work you could sub them in.

Has bastl gotten back to you?

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khyber
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Re: Bastl Spa expander for GrandPa, DIY help

Post by khyber » Tue Jan 14, 2020 12:13 pm

Nothing yet from Bastl, I pinged them again and resent the request via their web form. Hopefully I hear something back, they've helped me in the past when I've had issues with a DIY kit (missing part that time around though).

Thanks for looking over the picture though, the only thing I can imagine at this point is one of the ICs is bad (as you say) but I don't have a way to test this besides plunking some new chips in there.

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Noodle Twister
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Re: Bastl Spa expander for GrandPa, DIY help

Post by Noodle Twister » Tue Jan 14, 2020 12:42 pm

Hi, does your solder have rosin flux? If so those headers on the left need cleaning up. Best to clean it all up. You will be able to see any bad joints easier after a clean for yourself.

Middle leg of Potentiometer 3 , counting from the top, looks like it needs reflowing.

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brawnywynn
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Re: Bastl Spa expander for GrandPa, DIY help

Post by brawnywynn » Wed Jan 15, 2020 10:44 am

Wish I could be more helpful!

Best of luck!

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