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Have you made any progress?
I am very curious about the result.

I am completely new to the MIDI protocol, but I want to use it to switch my amplifiers and pedals. My pedals are then placed in a 19" rack and I only have my MIDI controller on the floor.
Now I have a Kitty Hawk foot controller, a Nobels ms-8 MIDI replay switcher and a DIY midi switcher from JimKim. But what strikes me now is that the program numbers do not match the number on my foot controller. For example, if I press switch 5, it will neatly read "05" on my foot controller. But on my receiver it indicates program "06". I have the idea that my foot controller counts from 0-127 (actually only from 0-99 since I only have 2 digits), because I can also set program "00". But my receivers count from 1-128. Can this just be true? And can this be changed?? My autistic brain would like to see 2 identical numbers:

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F362736262293

Above the link to the V2 version. I have copied the layout of the V1 version. All tracks and components correspond to the layout of the original.

If I look carefully, I should not measure anything on the outputs when there is no input. The clock signals present should control the MOS transistors. But as long as there is no input, can't a signal be transmitted? In my opinion this is not correct ..

Thanks for your comment. I have done some measurements around TDA 1022. I have my doubts about the measurement on pin 8 and pin 12. I initially test a 12V DC supply. And from 0.20 sec I do the measurement again but with a 9V battery.
0.00 sec -> Pin 1
0.04 sec -> Pin 4
0.07 sec -> Pin 8
0.12 sec -> Pin 12

0.20 sec -> Pin 1
0.24 sec -> Pin 4
0.27 sec -> Pin 8
0.31 sec -> Pin 12



There is no signal input. Is it correct that I do measure something on the 2 outputs of the BBD?

https://youtu.be/exUZ9JbGHng

Still the same problem with two 9V batteries. So the problem does not seem to come from the power supply. Now continue to measure where it can come from.
Someone tips? I have a scoop at my disposal.

A note was placed in the building description for the 11V zener: "* OMIT-Only needed if using the MP211 DC Converter"
So this is not necessary for the Recom DC / DC module.

I have a large box full of power adapters. Tried all I could. Also resorted to buying a few new ones specifically sold by music stores under the guise of "for pedals, no noise etc".
No luck with any of them. Always that same full-on hum when engaged. It seems all power adapters available are switch mode regardless of the blurb on the box, at least what I have are. Some say they're switch mode, some don't, which doesn't help. Only solution was a separate isolated power unit, which ironically is powered by a switching power adapter.

So basically you have 3 options. Get a proper isolated power unit (it's what they're made for afterall, ie fussy effects), come up with a better design of that circuits power section or run the circuit on batteries.

As I said, a single 9v battery doesn't have enough current, but 2 in parallel might do the trick. You could try it & being the same circuit as mine you would at least see if the hum is gone when it's engaged so you'd at least know if you're on the right track (isolated power being the cause) or whether to look elsewhere for a solution to the issue. Otherwise you'll end up going around in circles trying one switching power adapter or un-isolated power supply after another & getting nowhere.

It's a clone circuit that's extremely fussy about its power supply & I sure learned that the hard way, so I understand your frustrations, but what can I tell ya...

I'm going to try it tonight with two 9v batteries in parallel

Looks to me line V- IN should connect to common ground.

In version 2 it is explicitly said that this connection may not be linked to GND.

The layout has been copied 1 on 1 from the design of drog_trog.
So I would expect others to have this phenomenon too.

I can once again look for a 12V accu battery. Perhaps then I can exclude whether it is the power supply.

I just did a test with a 12V power supply with transformer and a switched power supply from Omron. But both power supplies give the same phenomenon.
You are talking about an isolated power supply, but I think every adapter with transformer is isolated. Isn't this always through the transformer?! In my opinion, the term "isolated outputs" only occurs in power supplies that have multiple outputs where the GND's are not connected to each other. But I don't think this applies to a single output. Correct me if I'm wrong.

I have now tested it with this adapter. Obviously not the best power supply. But I think I had the same problem with my other adapter, but this one is now at work. I am taking this home home this morning and, to be sure, I will test it again.

But you are almost certain that it must be a power supply problem?

See attached video

https://youtu.be/cp6Z_nfKiqM

What kind of noise? Hiss? Chirps? Whine?

I will make a sound clip later this evening. Can hardly describe it. Perhaps a sound clip says more.