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Post by 1953sbaalto on May 2, 2008 11:17:14 GMT -5
So I've decided to test my electrical engineering skills...(I'm a mechanical engineer)
I'm looking at using a super switch and a push pull pot to do the Mike Richardson 2.0 mod.
The pickups I'm using are the Custom Shop Fat 50s, which I believe only have a ground wire and a hot wire off of each pickup (should be here today UPS).
Can this be done? And does anyone have a complete schematic? I've been trying to sketch it out, but keep going in circles.
Thanks,
Jon
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Post by 1953sbaalto on May 2, 2008 11:43:40 GMT -5
Specifically what I'm looking to do is:
1)N 2)N+M 3)M 4)M+B 5)B
6)N*M*B 7)N*M 8)B*M+N 9)B*M 10)N+M+B
*Series +Parallel
I don't really want/need phase switching.
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Post by sumgai on May 2, 2008 15:15:33 GMT -5
Jon,
Hi, and welcome to the NutzHouse! ;D
The short answer is "yes", but the combinations may not be in the order you asked for. And I have to admit that I haven't worked it all out for myself, but it seems to me that what you are asking for might still require the 4PDT switch shown in Mike's diagram. What kind of push-pull switch did you order/already have in your hands?
HTH
sumgai
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Post by 1953sbaalto on May 2, 2008 18:53:06 GMT -5
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Post by ChrisK on May 2, 2008 19:06:29 GMT -5
Uh oh. I'm already concerned. (BTW, I'm an electrical engineer.) Good, since one does need both of these therefore. Ok, let's START by stating that these pickups (and most others) do not have a "ground" wire and a "hot" wire, but rather have a wire that is normally connected to the internal ground point and a wire that is normally connected to the internal signal output point. These designations are used in normal (pedestrian) guitar wiring to ensure proper output signal phasing. I start this "semantic trouble" anew again here since the MR scheme also connects pickups in series, which is confused by the artificial designation of wires from a pickup being the "ground" and "hot" leads. For the advanced wiring (and really all wiring, but then there's that whole tremo'Leo thing), I prefer to use "signal output" and "signal return" designations for the leads. Yes, done is. More or less, done is. Why, done is? (But fun is too.) These answers are related to the MR wiring scheme( s, there are a few), which already exist. (Hence the designation as the XXX scheme/mod/design/etc.) Now, do you want us to help you by directing you to the existing exact solution (which I know how to implement, and most recently discussed/posted with someone a'board), by helping you derive said solution (which we can do, but I won't since done is), or since you are threatening to "test your electrical engineering skills", watch you flap aboot fer a spell and then direct you to the existing exact solution.(which I AM willing to partake therein)? ;D ;D So, "neo-Sparky", what will it be? (BTW, the StewMac pp pot switch is a DPDT. There is a 4PDT pp pot, it's called the Fender S-1 pot/switch.)
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Post by 1953sbaalto on May 3, 2008 8:32:16 GMT -5
Chris if you good direct me to the exact solution, I would be much appreciative...
Thanks,
~Jon
P.S. It is wise to be concerned when a ME attempts to be a EE
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Post by ChrisK on May 3, 2008 13:19:38 GMT -5
Actually, no. It is more difficult to teach a ME things EE than an EE things ME due to the much more (although not as much with modeling today) abstract nature of "stuff". I'd spent the last 20+ years doing technology start-up companies for acquisition, so I've "not" done my share of mechanical engineering as well (it was my money in too, and when it's YOUR money................) Incidentally (co- since the threads have floated together), the MR thread for nearly the SAME thingy (MR 1.0) is adjacent to this one (ironiguana rewired his "ongoing testing of his EE skills" and has posted his resistance results. Mike Richardson wiring help ). I recommend that you also read my Discerning Paralleled Resistances and Guitar Wiring Diagnosis or....... posts for an engineering analysis of what one can glean aboot the internal state of wiring solely thru the output jack. I will respond to ironiguana's post with said type of analysis which will not only tell me if he has wired it correctly, but also the resistance value of his pickups and the wiring structures actually realized. As posted a few weeks back in (Another) Strat Mod please. Specific mods are difficult to find if they surfaced under another discussion topic. I readily found these by searching a'board for "mike richardson' for 500 days and 100 posts. Here's the original Mike Richardson Strat design (1.0) (well, after the super switch was changed away from the DiMarzio one). Here's the MR (2.0) one that does M and B * M + N instead of B + M and B * M. I haven't checked to see if it does B * (M + N) or (B * M) + N (Q.E.D.).
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Post by 1953sbaalto on May 3, 2008 18:29:24 GMT -5
Chris,
I've got that schematic, I was looking to make sure I am wiring the rest of everything correctly...I'll scan and post what I've got drawn up on monday when I get in. I'm just a simple ME...
I'm trying to work off of the 2.0...I've got the connections within the switch all wired up...
Thanks,
~Jon
P.S. will the push/pull i currently have sitting on my bench work, or do i need something better?
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Post by ChrisK on May 3, 2008 20:28:28 GMT -5
Yep. Have you looked at my post on the Mike Richardson wiring with phase? While it is MR 1.0, it gives an overall wiring as well as schematic form. One could identify the differences between the two MR versions (on the MR drawings) and extend this to my drawing. Anyway, it is another reference. Don't be misled by the phase switches; they are just "upstream" wiring modules between the effected pickups and the MR scheme proper. They are completely unrelated. Feldergarb!
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Post by 1953sbaalto on May 4, 2008 9:37:57 GMT -5
Thanks,
I've been using the MR 1.0 with phase as a reference, I think I figured out how to work around the extra push pull pots. I should be good to go, I'll let you know how it goes by the end of the week.
~Jon
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Post by ChrisK on May 4, 2008 13:10:57 GMT -5
Yeah, the phase switch/tone pot module has two "goes-inta's" (the pickup leads) and two "goes-outta's" (the tone pot connection points to the MR scheme). Just remove the switch part and connect the pickup wires to the tone pot and then to the MR wiring.
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Post by 1953sbaalto on May 4, 2008 19:31:27 GMT -5
I'm somewhere, just not where I need to be...first i lost my ground...and had nothing. Then after I fixed it, before screwing the pickguard back in, I decided to check resistances
Pot Down: (all in Kohm) 1) 17.64 (should be ~6) 2) 6.22 (should be ~12.3) 3) 12.10 (should be ~6.3) 4) 6.16 (should be ~12.5) 5) 6.16
Pot Up: 1)17.65 2)268.5 (Open - should be ~3K) 3) 4.10 (should be ~9K) 4) 268.6 (Open - should be ~3K) 5) 2.08
Basing the should bes off of ohm's law (i think ohm's - series add, parallel add inverse)
All with the pot down except for 5 concern me...
DC Resistances from the fender site: Bridge: 6.2K Middle: 6.3K Neck: 6.0K
Thoughts??? - I'm going to go over my wiring with a fine tooth comb tomorrow...will try to post diagram as well.
Thanks,
~Jon
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Post by 1953sbaalto on May 5, 2008 7:18:40 GMT -5
my scanner did somethign funny, so the scale is screwed up... I know I have my leads reversed on the middle pickup, besides that i'm lost...
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Post by D2o on May 5, 2008 8:53:32 GMT -5
my scanner did somethign funny, so the scale is screwed up... I know I have my leads reversed on the middle pickup, besides that i'm lost... Yes, it sure did - it was HUGE .... Here:
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Post by sumgai on May 5, 2008 12:14:58 GMT -5
Jon, Methinks you've forgotten MR's cocktail-napkin exhortation: connect the A's and X's together. I don't see anything between terminals 1, 2 and 3 of the M+ pole and the hot side of the volume control - the two "A" connection labels. Your Middle pickup is phased correctly, but your Neck pickup is reversed. Still, that only affects the tone, not the actual pickup selection, so it's not the cause of your problems. Plus, take a closer look at your tone controls, I don't think either of them is doing you any favors. Hint: when dealing with tone controls in a series connection, you cannot connect them in the usual fashion of "hot" lead to one side of the cap, and the other side to the pot and thence on to ground. If you select a series connection with that scheme, you'll kill some or all of the output. The answer is to connect the cap-and-pot directly across the desired pickup. That way, the control works for both parallel and series selections. HTH sumgai
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Post by 1953sbaalto on May 5, 2008 13:44:25 GMT -5
I meant Neck...
I think I have my As and Xs connected. I'll correct the cap issue later. - To be correct, I need 2 caps?
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Post by ChrisK on May 5, 2008 20:03:36 GMT -5
For the tone controls to work correctly (if at all) they need to be across just the pickup that they're for. This means two caps and NO common connection.
Connect the bridge pot and cap directly across the bridge pickup at the mega switch. This will be bridge (+) and local ground.
Connect the neck pot and cap directly across the neck pickup at the mega switch. This will be "out" and neck (-).
I would fix the tone circuits FIRST since the inadvertent paths thru them may be causing at least some of your problems.
I'm also unclear on just what the tone pot drawings mean. The volume pot is clear due to the presence of the attached switch. A small circle indicating the location of the pot body would be most helpful. I suspect that you are showing the usual Strat orientations, but I can't be sure.
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Post by 1953sbaalto on May 5, 2008 22:03:06 GMT -5
Thanks, I'll take a look tomorrow after work and let you know how that works out...and yes they should be the standard start orientations
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Post by ChrisK on May 5, 2008 23:05:02 GMT -5
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Post by 1953sbaalto on May 6, 2008 6:19:54 GMT -5
Chris, if this works, and you're ever in the new haven, ct area, send me a message, i'm buying you a beer!
Can't wait to get out of work tonight.
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Post by 1953sbaalto on May 6, 2008 21:43:01 GMT -5
still in the dark... Values now: (kOhm) Pot Down: 1) 5.94 2) 5.90 3)2.68 4) 268 5)17.35
Pot Up
1)17.49 2)11.87 3) 5.92 4) 268 5) 5.91
I'm wondering if I toasted my caps when i connected them...
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Post by sumgai on May 7, 2008 0:13:26 GMT -5
Chris, Same as Jon, I don't see (on your modded diagram) where the A's are connected. The volume control's Hot terminal should be getting signal from: terminals 3, 4, and 5 of the Middle '+' pole; terminal 5 of the Bridge '+' pole; the diagonal pins on the DPDT switch; and the Neck '+' lead. Of the bunch, only the Neck '+' lead is shown at the Hot terminal....... (I've reversed the numbering from my previous post, I has somehow forgotten that MR assembled his diagram backwards, numbering the positions from right to left instead of the usual way. ) ~!~!~!~!~!~!~!~!~!~ Jon, I missed it last time (nor did Chris catch/correct it), but you also don't show a connection from Middle '-' to ground at terminal 2. I know that it's sometimes a real bear to draw something out like this, but the upside is, as you see a connection on the guitar, you check it off on the original schematic, and then draw it on paper, before moving on to the next connection. When you're all done, there should be a check mark by each wire on the schematic. Since I didn't do the job, and since I don't have the article in front of me to make the drawing myself, I have to trust that you drew what you saw, and only what you saw. That leads to my concerns, outlined above. Until you swear on a stack of Bibles that the drawing (this one or a new one) is correct against both the guitar (as-built) and against the schematic, then I don't want to spend time on guessing why Position 4 doesn't work.......... it'd be too much like work or sumpin'. And no, your caps aren't toasted. If either of them were, then you'd know it - either the control would do nothing, or it'd make like a volume control, and kill all signal when turned down. HTH sumgai
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Post by ChrisK on May 7, 2008 11:50:17 GMT -5
I didn't look at and hence did not address the rest of the drawing,
The "interwoven" tone control circuits were enough in my mind to cause me to correct them prior to any further analysis of any other part of the circuit.
Now that we have new values post (hopefully) tone control correction, we can do a nostril analysis.
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Post by ChrisK on May 7, 2008 12:07:09 GMT -5
Ok, we have some new values. This will be much harder than it should be. When I talk about using a 5K/10/20K values for the three pickups to test the wiring (neck is 5K, middle is 10K, and the bridge is 20K), I mean it.
If you replace the pickups with these values of fixed resistance, it will be quickly obvious what's going on. Get 5 each 10K resistors.
Put two in parallel across the neck pickup connection points (5K).
Put one across the middle pickup connection points (10K).
Put two in series across the bridge pickup connection points (20K).
Values now: (kOhm) Pot Down: 1) 5.94 (one pickup) 2) 5.90 (another pickup, but just one) 3)2.68 (two in parallel) 4) 268 (Volume pot only, someone's AWOL) 5)17.35 (?three in series - wrong time zone)
Pot Up
1)17.49 (?three in series - right time zone) 2)11.87 (?two in series) 3) 5.92 (?one in series, someone's "short's" are in a, uh, short) 4) 268 (Volume pot only, someone's "short's" are open) 5) 5.91 (?three in parallel - sometwo's AWOL)
Listen to sumgai, wires are awry.
Also, based on your pictoral for the volume pot, it appears to be wired backwards (ground and hot terminals reversed). Are you wiring this left-handed?
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Post by 1953sbaalto on May 7, 2008 13:01:03 GMT -5
I know my volume pot is drawn backwards, but i wired it opposite of what's drawn...
Another trip to radio shack tonight...should have values by 8pmish...(eastern)
i also found one of my missing connections today looking at the sketch over lunch
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Post by 1953sbaalto on May 7, 2008 17:54:55 GMT -5
~5K at neck, 10K at middle, 20K at bridge
READINGS: Pot Down: 1) 4.75 2) 3.208 3) 9.52 4) 6.27 5) 17.27
Up: 1)21.46 2) 10.82 3)3.21 4)25.65 5)2.75
also, connected the As to the hot side of the volume pot (was missing connection before)...
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Post by ChrisK on May 7, 2008 20:57:56 GMT -5
~5K at neck, 10K at middle, 20K at bridge
READINGS: Pot Down: Note: readings lower due to vol/tone pots. 1) 4.75 (Looks OK s/b 5K) 2) 3.208 (Looks OK s/b 3K33) 3) 9.52 (Looks OK s/b 10K) 4) 6.27 (Looks OK s/b 6K66) 5) 17.27 (Looks OK S/B 20k)
Up: 1)21.46 (B*N, middle shorted) 2) 10.82 (s/b ~15K) 3)3.21 (M+N, bridge shorted) 4)25.65 (Looks OK) 5)2.75 (Looks OK)
Are you sure that you corrected the tone circuits?
Could you correct your drawing to reflect its current state?
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Post by 1953sbaalto on May 7, 2008 21:14:59 GMT -5
Will draw up tonight, scan in the AM at the office.
edit: drawn up /edit
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Post by 1953sbaalto on May 8, 2008 7:25:59 GMT -5
This is drawn up as wired last night with the exception of currently using a 5K, 10K, and 20K resistor in place of the pickups. ( edited by sumgai to show the image, a wee bit larger than a thumbnail. )
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Post by sumgai on May 8, 2008 14:15:29 GMT -5
Jon, Allow me to humbly suggest that you check out the red arrows: Interestingly enough, your first iteration (of this area) matched the schematic, but now........... Fortunately the fix is easy, just move one wire, and add a jumper. HTH sumgai
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