From DJ Maytag Sent Wed, Sep 5th 2018, 16:54
Having just restored a 101 from one of your survival kits earlier this = year, I knew that volume pot was a 100K, so I caught what you meant. :) Is it odd for Roland to design a product and not use similar parts from = other machines? I=E2=80=99m scouring service manuals from items also = released in 1982, and nothing else uses this volume pot. I thought they = were =E2=80=9Cbudget conscious=E2=80=9D (aka cheap) and tried to buy in = bulk and make various designs use similar parts? > On Sep 5, 2018, at 11:34 AM, Sam Mims <xxx@xxxxxxx.xxx> wrote: >=20 > Yikes, I see that I made a typo... In the second paragraph, I wrote: >=20 > 'Most notably, the SH-101 pot is a 10KA, while you need a 100KA.' >=20 > In the words of Willy Wonka (rev 1.0, Gene Wilder version), 'Strike = that, reverse it!' That line SHOULD read: >=20 > 'Most notably, the SH-101 pot is a 100KA, while you need a 10KA.' >=20 > Sorry for the confusion! >=20 > Sam Mims > Syntaur >=20 >=20 >=20 > On 9/5/2018 11:10 AM, DJ Maytag wrote: >> Thanks Sam! Looking at the service manual, it shows 3 legs and 2 side = mounting lugs. It appears to be pretty munch identical to the layout of = the 101 volume knob. If push came to shove, and I couldn=E2=80=99t find = an exact part, would sticking a higher resistance part (i.e. the same = one for the SH-101 volume) in it and then reducing the value of R1 (or = removing it and putting in a jumper) after the volume pot end up get = close to the same output level as using the correct part? >>=20 >> I=E2=80=99ve got a backlog, so I won=E2=80=99t be able to open it up = and take pics for a bit. I=E2=80=99m not being lazy, I swear! :D >>=20 >>=20 >>=20 >>=20 >>> On Sep 5, 2018, at 10:16 AM, Lorne Hammond <xxxxxxxx@xxxx.xx> wrote: >>>=20 >>> nice post Sam! >>>=20 >>> lorne >>>=20 >>> -----Original Message----- >>> From: Sam Mims <xxx@xxxxxxx.xxx> >>> Sent: September-05-18 8:08 AM >>> To: DJ Maytag <xxxxxxxx@xxxxxxxx.xxx>; Analog Heaven = <xxxxxxxx@xxxxxxxxx.xxx> >>> Subject: Re: [AH] Roland parts cross reference/compatibility chart? >>>=20 >>> Matching parts like this is a tricky game. I spend a crazy amount = of time at it, and have lots of incorrect parts to show for it! (And = thankfully, a decent number of correct ones also...) You can easily get = lost in a rabbit hole. >>>=20 >>> You are correct in that the SH-101 pot is from the same supplier - = the 'EVH...' part numbers say that they are both Panasonic parts. But = the devil is in the details. Most notably, the SH-101 pot is a 10KA, = while you need a 100KA. In Panasonic-speak, the 'A14' at the end of the = part number designates this - the SH-101 pot ends in 'A15'. >>>=20 >>> And all of those other numbers before it designate things like the = type of shaft (knurled, flatted, round?), the length of the shaft, etc., = all of which are critical. >>>=20 >>> My mental process in finding a replacement goes something like this: >>>=20 >>> (1) Find pots that are electrically correct - i.e. same resistance = and taper. Theoretically, you can make any of these work, though you = may have nothing better than a strange pot dangling by the wires. >>>=20 >>> (2) Narrow your search to those that physically fit - both mounting = to the PCB (if applicable), and fitting within the confines of the = synth. Do you need a panel-mount or PCB-mount pot, for instance? Some = PCB-mount pots have three solder pins, some have four (the fourth is = either a dummy or a center tap). Dual pots may have 6 or 7 pins. >>>=20 >>> (3) Once you find pots that can actually mount in the synth, find = the ones with the correct type of shaft. If your other pots (and hence = the >>> knobs) are flatted D-shaft, then you will want a replacement pot = with this type of shaft. If it's a D-shaft, things are further = complicated by the orientation of the flat - if this is wrong, once the = knob is installed, it may be pointing 180 or 90 degrees out of whack. = And of course, the shaft needs to be the correct length. Too short = won't work, of course, too long can be solved by a cutting wheel. >>>=20 >>> (4) Other considerations include: Solder lugs or PCB pins? If PCB = pins, they need to be oriented correctly. Do you need a pot with a = center detent or not? If it is a 4-pin pot, do you need a center-tap = pot or not? >>>=20 >>> So you can see that it gets pretty complicated! I often think that = what we sell at Syntaur is not so much the part itself, but all of the = legwork it takes to figure that part out. And in a number of cases, = when the perfect match is not to be found, we sell a pot that has the = shaft already cut to the correct length or something like that. >>>=20 >>> If you like, you can email me a photo of the pot you need, and I can = look through our database and perhaps find a good replacement among the = 10KA pots we carry. >>>=20 >>> Sam Mims >>>=20 >>> Syntaur >>>=20 >>>=20 >>>=20 >>> On 9/5/2018 8:00 AM, DJ Maytag wrote: >>>> Hey all, >>>>=20 >>>> I=E2=80=99m looking for an A10K volume pot for a Roland EP-11 = (Piano Plus 11), and can=E2=80=99t see to find this part used in other = Roland gear made in 1982 (closest thing is an A100K used in the SH-101 = that appears to be from the same supplier). The Roland part # is = 13219240 and the supplier # is EVH-5XAP20A14. >>>>=20 >>>> Any thoughts on where to find this? It=E2=80=99s in pretty decent = shape, works very well (aside from the volume pot and a couple sound = selector switches), and I=E2=80=99d rather restore it than scrap it for = compatible parts. >>>>=20 >>>>=20 >=20