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Merman switching board V2 vs V3

Started by PeroPorque, May 05, 2020, 09:14:58 PM

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PeroPorque

So a few months ago I populated a Merman PCB, and after some failed troubleshooting, decided just to start over. The prior PCB I received included switchboard V2, but now it's upgraded to V3. Awesome. I just want to clear up whether to include two resistors for the Merman, since it's not 100% explicit in the instructions. I think the answer is no, but I don't want to risk effing this up again.

- The Merman instructions say to leave TC7662B off of the switch board, as well as the two nearby 47uF electrolytic caps and the 10k resistor (R6 for the switchboard V2). This is seen most clearly on the wiring diagram (page 5) of the Merman instructions PDF.
- The PDF instructions for the V2 board say to leave off the above, and also omit the 8k2 resistor (R5) for projects that don't use split-rail (which would include the Merman).
- I have the V3 board now, and I'm going to leave off the IC and two ECs as per Merman instructions. From the schematic, it looks like I should also leave off the R5 and R6? I don't really understand split-rails power, but I'm making an inference because they're only linked into the circuit via the IC and ECs which should be left out.

gordo

You'll only be using the parts highlighted in green (which is a challenge if you print it in B&W) on the switch board build guide and your zener will be 13v on the Merman.  I've build most of these VFE's and I STILL do a double take everytime I build the switch board :-)
Gordy Power
How loud is too loud?  What?

PeroPorque

Thanks for clarifying. It makes more sense now looking back at the the color coded list of components. I just taped off that area on the switch board so I don't forget and populate it later...