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New VFE switching board

Started by madbean, November 05, 2017, 02:44:28 PM

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madbean

The re-designed switching board for the VFE projects is complete. In the end, I decided to go with the version that offers the best compromise. Note: I put some of my wires on the bottom on this prototype...they should go on the top!

Changes:
1/4W resistors instead of 1/8W
Board mounted jacks (these are pushed a little closer together to make fitting it in the enclosure a easier)
Wired DC jack.
Kept the battery option (although I like to discourage battery use).
Can use regular TRS or TS jacks - no longer need the "make" style and no work-around needed.
Can still use non-mounted jacks if you prefer...just use wires (all this will be explained in the new doc).
The micro-controller now has two decoupling caps - a 100n across the rails and a low-profile 4u7 electrolytic.

Board is almost exactly the same size as the previous one, as well. So, overall an improvement as far as making it easier to build for the largest number of people. It will fit the existing drill template but I will make one small change for those using TRS style power jacks instead of the Lumberg style (my preferred).

I'll be ordering a couple hundred of these this week as well as getting some more micro-controllers from Peter soon.

EBK

I need to ask a naive question.
How do board mounted jacks work with the 2° draft angle of die cast enclosures?  Do you mount them to the board at a matching angle?
"There is a pestilence upon this land. Nothing is sacred. Even those who arrange and design shrubberies are under considerable economic stress in this period in history." --Roger the Shrubber

madbean

#2
Quote from: EBK on November 05, 2017, 06:53:42 PM
I need to ask a naive question.
How do board mounted jacks work with the 2° draft angle of die cast enclosures?  Do you mount them to the board at a matching angle?

That isn't necessary. The angle of the side wall will create a small gap on a portion of the jack but since there are two anchors (two jacks) the effect is negligible. The jacks themselves may not both be in full contact with the sidewalls but the insert screws that hold them in place are (more or less).

gordo

Short answer: they work well.

Long answer:  Technically, yes, you should.  Can be easily accomplished by tack soldering the inner most pins of the jacks, locating the board, mounting the jacks and then finish soldering.

In reality I don't think it makes a whole lot of difference.  Especially if you're using a set of fiber washers to shim them.  The bigger culprit is cranking down the jacks too tight (whether angled or not) and/or stepping on the 1/4" plug (which puts WAY too much pressure on the jack.  That is inherent to board mounting jacks anyway, so it's a trade off between ease of build and roadworthy-ness.  Then again Lumbergs and to some extent even Switchcraft won't pass the torture test all the time either.

I've repaired a whole lot of SansAmp type pedals (which are a bitch to get apart) and a whole lot of chassis mounted jacks. Chassis mount are always sturdier and easier to fix.  Board mount are easier to build and look nice.
Gordy Power
How loud is too loud?  What?