Re: [AH] Roland parts cross reference/compatibility chart?

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:
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> Yikes, I see that I made a typo...  In the second paragraph, I wrote:
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> 'Most notably, the SH-101 pot is a 10KA, while you need a 100KA.'
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> In the words of Willy Wonka (rev 1.0, Gene Wilder version), 'Strike =
that, reverse it!'  That line SHOULD read:
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> 'Most notably, the SH-101 pot is a 100KA, while you need a 10KA.'
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> Sorry for the confusion!
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> Sam Mims
> Syntaur
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> 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?
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>> 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
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>>> On Sep 5, 2018, at 10:16 AM, Lorne Hammond <xxxxxxxx@xxxx.xx> wrote:
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>>> nice post Sam!
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>>> lorne
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>>> -----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?
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>>> 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.
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>>> 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'.
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>>> 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.
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>>> My mental process in finding a replacement goes something like this:
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>>> (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.
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>>> (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.
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>>> (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.
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>>> (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?
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>>> 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.
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>>> 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.
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>>> Sam Mims
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>>> Syntaur
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>>> On 9/5/2018 8:00 AM, DJ Maytag wrote:
>>>> Hey all,
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>>>> 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.
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>>>> 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.
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