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Happy Birthday!

Remove it I would think... would have to check the schematic

Happy Birthday!

If you get in a bind for prototypers, always happy to help.

You got that right. A great man, and all sports stars really have him to thank for their obscene paychecks and opportunities. I remember my dad always liked him, disliked Nicklaus (because of Nicklaus beating him regularly) and liked Tom Watson, probably because of Watson beating Nicklaus. I ran into him in the parking lot at the Ameritech Senior Open back in the '90s (with my dad) and recall how personable and approachable he was. RIP.

After confirming the pinout of the Alpha 4-gang pot, I don't see any way of integrating this into the 3-pot board. The 2nd row of pins (tap) from the left are electrically active, so cannot touch any existing pad on the board. No way to do it in my playing around with the board, short of giving it its own space on the board. Add to this the difficulty in sourcing the part. I am going to go with what I have, and will generate what I hope are the final gerbers in the next couple of days. Seeed has not responded to my email, so hopefully they are fine with the slots for the 16 pins on the 4CP2500, and fine with the additional 2 slots to mitigate drill overlaps. Slots should be cut before any other steps on the board, including drilling. All slots need to be thru-plated, so Michael, please note that to Seeed when you place the order(s).

I'd agree on the assessment regarding the Song Huei pots, as they even share the numbering (2142G) as cspirou noted. They also give a complete schematic matching Kerry's board layout. Since I believe he built one, I would assume it works Other than the TKD CP601, this pot is the smallest of the lot (TKD CP2500, Alps RK27), so keep that in mind Kerry before you offer to use a different pot. I hadn't heard much in terms of reputation regarding sound quality of the Alpha pots vs. the RK27 and the TKD CP2500 (or 601). I know that I have liked the one CP2500 that I used, quite a bit better IMO to the RK27. I also hadn't realized that Justin was using these for a time in the GSX, but he also is crazy enough to buy 1000 at a time

Can't read the CAD files (no software), so no help there. Datasheet says 1.57mm/0.062 which I'm sure you saw. You have some interesting projects going on!

OK... Normally, #1 pin is the lower left (which from the bottom would be the upper left, I guess). The "schematic" Alpha has on their website labels the pins 1-3, so I assumed that pin 4 in each row was the open or loudness or whatever pin. I can't find any mention of this on their website, and they don't seem to have complete datasheets. Seems like a typical CA company, with their website and all Where can you actually buy these things, as they have a 1000 pc. min order?

^ That doesn't match what Kerry did on his boards from L-R top (or front): 1 - 2 - 3 - 4 Gnd open output input (wiper)

Nope. Wire as labeled on the board I1-I4, so normally L+/L-/R+/R-. O1-O4 go to the board inputs in the same manner. Or be different and do R/L

Yeah, I hadn't looked at that. Isn't it $2.26 for a package of 100 Guess not...

Happy Birthday Jim! Hope you are enjoying things in Florida!

Good info from Gordon Rankin. Kind of a big leap of faith with the writer making this statement however: Bringing it all back home, the iFi iPurifier 2 likely improves the sound of the Sonicorbiter SE because it minimises transmission errors by making lighter work for the Mytek Brooklyn’s USB receiver chip. I would think that the purifier may be changing the error(s), but whether it is actually minimizing anything can't really be determined without looking at it as Mr. Rankin does.

From looking at Kerry's layout, it looks like he is connecting pins 1 (gnd), 3 (output?) and 4 (input) on the pot. I assume that I am looking at the right pot (Alpha 21mm 3RP-2142G, from Alpha in Oxnard, CA)? There is also a Taiwan Alpha and a Korean Alpha, but the pots I find from there aren't 4-ch, look nothing like this one, etc. The data I found on the CA Alpha company website just shows pins 1-3 on their schematic diagram, so I assumed the 4th pin (right side row) were loudness or unconnected. I also made the assumption that the pin numbering starts from the left lower corner: 13 14 15 16 9 10 11 12 5 6 7 8 1 2 3 4 If anyone has the correct datasheet or a link... this is what I was looking at. http://alphapotentiometers.net/html/21mm_pot_4.html

I defined a library part for the Alpha 3RP pot and played around with it on the current 3 pot board to see what the pin layout was like. As you can see from the pic below, it might be possible, but there would be some drill overlaps, and the pot would have to be offset 2mm due to the 4 pins per row instead of 3.

Anything is possible, but probably not happening. I still haven't figured out what the 4th pin per row is for and the datasheet doesn't seem to define it. I'll have to examine the gerbers for Kerry's board more...

That thing is sweet Kerry! Really nice job. What layout software were you using? Also, what pot is this set up for? Alpha? Would a TKD601 work? Ooops, just figured out what pot you are using, so no go on that

Like these?

I'm still waiting to hear from seeed regarding any issues with the slots and drill holes. I really don't know why someone would want the 2 TKD pot only board when the one that does all 3 is the same size/price. Also, I haven't updated that board in a few days. As for channel / gang mapping on the pots, this version only swaps gangs 3 and 4 on the RK27 (ch 3 goes thru gang 4, ch 4 thru gang 3 of the pot). Otherwise, straight ch # to gang #.

Still waiting for seeed to get back to Michael or I regarding any problems with the board, but based on some feedback/suggestions on an eagle support forum, this should be close to final. I placed the Molex/Phoenix jacks right on top of one another, which is the way I do it when I add these to an existing board. Slots are now filled rectangles rather than hollow rectangles, so should be easier for seeed to figure them out. For the bad pin overlap on row 3 of the Alps and row 4 of the CP601 center pins, I added a milled round slot and rectangular pads to top/bottom. For the overlap on row 1 center pins of the CP2500/Alps RK27, I added a milled slot. Board is 46.6 x 35.4 mm. I also redid the 4CP601 only board with the overlapping connectors. Of course I'm probably the only one who cares about these far superior connectors

Very nicely done! Who/where is the case from? Agree that the wiring could probably be cleaned up a bit, maybe a pcb for the pot wiring would help? Routing down the center like you did is good though.

Happy Birthday!

hanks UFN! I did a layout that supports all 3 pots (4CP601, 4CP2500 and Alps RK27114). Similarly to Birgir's layout, this one would allow cutting to support a stereo pot if desired. 46.5 x 35.2 dimension

Not true.