Hammond H-112 Percussion Mod

[ELPFan15]

If you found two wires of the same color on either of the tabs that you cut off, you have to splice the two wires together and insulate them. I would use solder and a twist of wire, and some scotch 33 electrical tape (HF electrical tape doesn't stay stuck). As T200 said , the overtones are daisychained through the tab switches. I should have thought of that, sorry.
I bought some 1 mf, some 6.8 mf and some bigger electrolytics for my SS percussion amp, I think they were 47 mf or something. I bought ceramic dielectric +-10% caps for the 1 and 6.8, no sense buying tantalum caps that wear out in 10-20 years all over again. I think the red end of the tantalums is plus. I haven't installed caps yet , I have to trace the H100 connector and make sure they don't use the pin that the 400 V comes in on the tube amp for something else, before I install that chassis.

Do you mean splice the wires that aren't 2nd and 3rd harmonic back together, but bypass the switch?

[indianajo]

Do you mean splice the wires that aren't 2nd and 3rd harmonic back together, but bypass the switch?

Yes. {this makes ten characters. }

[ELPFan15]

I soldered the wires to the other terminal of the switch controlling them(always on). That's essentially what we're going for, right? (If not, shows you what happens when I think. heh.)

[indianajo]

Interesting, but probably not correct. I don't know what this other terminal of the switch does, or connects to. I was sort of envisioning the two wires for fifth harmonic that used to be soldered to a switch terminal on the banjo tab (for example) hanging out in the air soldered together with electrical tape on them. Any two color wires but green and yellow. Green wires stay where they were on banjo and yellow stay where they were on guitar (or vice versa, or two other sacrificial tab switches).
If there is a risk of the wires getting tangled in something, you could buy five terminal strips from electronicsurplus.com or tubesandmore.com and wood screwing them down, and soldering the surplus two wires to them, a pair to each terminal, color matched.

[ELPFan15]

Interesting, but probably not correct. I don't know what this other terminal of the switch does, or connects to. I was sort of envisioning the two wires for fifth harmonic that used to be soldered to a switch terminal on the banjo tab (for example) hanging out in the air soldered together with electrical tape on them. Any two color wires but green and yellow. Green wires stay where they were on banjo and yellow stay where they were on guitar (or vice versa, or two other sacrificial tab switches).
If there is a risk of the wires getting tangled in something, you could buy five terminal strips from electronicsurplus.com or tubesandmore.com and wood screwing them down, and soldering the surplus two wires to them, a pair to each terminal, color matched.

Before and after. What I did is seen by the yellow wire on the first pic.

[ELPFan15]

I tried my way, and it didn't work. So, maybe third time's the charm.the reason I did the soldering anyway was because it seems a lot of wires are routed under the switches.

[indianajo]

Well, appreciate your patience. Life is more complicated. i took mine covers off tonight. White/red wire is percussion keying, you can't take that one off. It turns into a brown wire at chimes then runs uninsulated down to xylophone where it turns brown again and goes to the back of banjo. You can't take that one off, it triggers the percussion. There is an orange back for percussion keying, you can't take that one off either. There is an orange fundamental tone wire goes only to guitar, glock and marimba, that one you could take off guitar if you are reusing guitar. What other one are you using besides banjo? Which one is going to be two and which one is going to be threes? Looks like at banjo you take off blue, white, voilet, grey, white/brown. Then take off either green for twos or yellow for threes. There is stuff on top and bottom, it is going to take me more time to figure out if in is the top and out is the bottom, or vice versa. Stay tuned. Sleep now.

[ELPFan15]

Well, appreciate your patience. Life is more complicated. i took mine covers off tonight. White/red wire is percussion keying, you can't take that one off. It turns into a brown wire at chimes then runs uninsulated down to xylophone where it turns brown again and goes to the back of banjo. You can't take that one off, it triggers the percussion. There is an orange back for percussion keying, you can't take that one off either. There is an orange fundamental tone wire goes only to guitar, glock and marimba, that one you could take off guitar if you are reusing guitar. What other one are you using besides banjo? Which one is going to be two and which one is going to be threes? Looks like at banjo you take off blue, white, voilet, grey, white/brown. Then take off either green for twos or yellow for threes. There is stuff on top and bottom, it is going to take me more time to figure out if in is the top and out is the bottom, or vice versa. Stay tuned. Sleep now.

Banjo is third, and guitar is second. Maybe I accidentally cut the trigger wire.


EDIT:Yep, I accidentally cut it. I resoldered it back to it's former place, and double checked everything. I'll try it when I get up tomorrow, it's too late to turn it on now(2 am here).

[indianajo]

If that works, great, if not, here is my next theory. These switches have a pass through function, you've got to pass through the wires your remove to the top of the transformer to maintain the other tabs. Banjo continues to be my least favorite sound, So leave green on it, it will be threes. Also red/white (turned into brown) has to stay on it. Next to it is xylophone, it already has twos on it (yellow) which you leave on it, also the red/white (brown) . You remove the grey from xylophone, that is sixth. Unfortunately there are 3 or 4 grey wires on xylophone, and they are all connected together with the tab up or down. The console wiring diagram 42 indicates one wire is gra and one is grn, but all mine are gray, and the schematic indicates they should be gra and yel on xylophone. I can't get my meter probe in to determine what is going on at the bottom, but there are a lot of wires down there. What serial # is your organ, the keyboard-partner.de schematic is for ser 15000 up and my organ is ser 7xxx.

[ELPFan15]

If that works, great, if not, here is my next theory. These switches have a pass through function, you've got to pass through the wires your remove to the top of the transformer to maintain the other tabs. Banjo continues to be my least favorite sound, So leave green on it, it will be threes. Also red/white (turned into brown) has to stay on it. Next to it is xylophone, it already has twos on it (yellow) which you leave on it, also the red/white (brown) . You remove the grey from xylophone, that is sixth. Unfortunately there are 3 or 4 grey wires on xylophone, and they are all connected together with the tab up or down. The console wiring diagram 42 indicates one wire is gra and one is grn, but all mine are gray, and the schematic indicates they should be gra and yel on xylophone. I can't get my meter probe in to determine what is going on at the bottom, but there are a lot of wires down there. What serial # is your organ, the keyboard-partner.de schematic is for ser 15000 up and my organ is ser 7xxx.

Serial # is A-34903. I did get the percussion to work, just not with the right harmonics. Banjo still sounds like a mixture of harmonics, and guitar has only one harmonic, though I don't think it's second or third(it sounds higher than both).

[muckelroy]

Banjo is third, and guitar is second. Maybe I accidentally cut the trigger wire.

Paddle faster. I hear banjos.:->

j/k. Interesting stuff, keep us posted!

[indianajo]

I think the harmonics come in from the right, the low keys end, start at the chimes and sweep through the switches to the banjo and out to the 9 pin and 12 pin connectors on the preamp. The keyboard-partner.de percussion schematic should pertain to your high serial # unit. The secret is maintaining the wires coming from the bottom contact on the schematic (Normally Open contact) through to the bottom of the transformer input, while cutting off the wire that go to the pole and Normally Closed contact of the tab switch for everything but the desired harmonic on a switch (second for guitar or xylophone, third for banjo). These two wires that used to go to pole and NC, you twist together and insulate. Put the guitar tab back where you found it, unless you can figure out which contact is pole, which is Normally open, and which is normally closed contact (the upper one on the schematic.) These are multipole double throw switches, with no center off position. Unfortunately it is high summer and I have to make progress on getting out to my country property and getting it mowed before my neighbors lynch me or call the county government on me. So, I haven't figured out which terminal of a tab switch is the pole, and which is the NC and which is the NO. Upper on the schematic, probably is not physically upper terminal. Also haven't figured out how to get to the bottom contacts (physical) to remove them or even to measure them. I think perhaps the back cover of the tab box with the 6 preamps PWB has to come off, which is a bit scary.
figure 42 console wiring of the archive.org H100 service manual should be some help, but it is so fuzzy I can't read the colors. I believe that schematic is for an early serial number unit. The 4 grey wires on my xylophone switch indicates that Hammond didn't worry too much about the colors anyway, or at least not that day. The best way to check which wire is which coming in is to check from the input connector over on the right. Which of the 4 connectors at the right is P605 (input harmonics) is also to be determined.

[indianajo]

okay, it's dark and my arms are tired from making car parts. The normally open side of the tab switches is the upper keys side, left viewed from back. The normally closed side of the switch is the lower keys side, right side. So where the two switches are connected together across the top with bare wire, that make the bare wire the pole of the double throw (form C) switch. So to pass through a harmonic on a switch (not allow that switch to connect it to the bottom of the transformer, but let the other ones through) you have to remove the wire from the top (pole) and the right bottom (NC) side and solder them together. I still haven't figured out how to get to the bottom of the switches to unsolder wires. Maybe you can un-harness the bundle and do it there, instead of removing the back.
This theory remains to be tested by experiment. Fading out for the day.

[ELPFan15]

I think the harmonics come in from the right, the low keys end, start at the chimes and sweep through the switches to the banjo and out to the 9 pin and 12 pin connectors on the preamp. The keyboard-partner.de percussion schematic should pertain to your high serial # unit. The secret is maintaining the wires coming from the bottom contact on the schematic (Normally Open contact) through to the bottom of the transformer input, while cutting off the wire that go to the pole and Normally Closed contact of the tab switch for everything but the desired harmonic on a switch (second for guitar or xylophone, third for banjo). These two wires that used to go to pole and NC, you twist together and insulate. Put the guitar tab back where you found it, unless you can figure out which contact is pole, which is Normally open, and which is normally closed contact (the upper one on the schematic.) These are multipole double throw switches, with no center off position. Unfortunately it is high summer and I have to make progress on getting out to my country property and getting it mowed before my neighbors lynch me or call the county government on me. So, I haven't figured out which terminal of a tab switch is the pole, and which is the NC and which is the NO. Upper on the schematic, probably is not physically upper terminal. Also haven't figured out how to get to the bottom contacts (physical) to remove them or even to measure them. I think perhaps the back cover of the tab box with the 6 preamps PWB has to come off, which is a bit scary.
figure 42 console wiring of the archive.org H100 service manual should be some help, but it is so fuzzy I can't read the colors. I believe that schematic is for an early serial number unit. The 4 grey wires on my xylophone switch indicates that Hammond didn't worry too much about the colors anyway, or at least not that day. The best way to check which wire is which coming in is to check from the input connector over on the right. Which of the 4 connectors at the right is P605 (input harmonics) is also to be determined.

So everything on the bottom switches should be left as is, and I'm guessing splice the unused harmonic wires right before the transformer/preamp?

[indianajo]

The bottom switches on the schematic, the NC switches, you leave alone. These are physically on the upper keys side of the switch (right from back) , and have a bottom & top solder terminal. On banjo you remove the wrong color wires going to the bare bussed tops (poles) and move them the the right bottom (NC)'s of the same contact. The one left alone was going to be green on banjo, wasn't it? Yellow runs over to banjo from the front of top(physical) of xylophone to the bottom(physical) of banjo as a bare wire, I'm getting too sleepy to figure that out right now.
Before doing any more modding, put guitar back to stock and see if you can get the other percussions besides banjo to work normally, as they did before you did anything. If that doesn't work, try putting banjo back to normal, though you can aligator clip lead your wrong color wires back to their terminals since you're going to take them back off again to move to the bottom of NC side. If you can't get back to normal, ask questions and I'll describe the wire order or something- I can't read it off the archive.org print, although captain-foldback.com's sliced up print might be more legible for the colors.