Hammond H-100 issues

[Stanislao]

Finally got my 1969 H-182 running again, the pig is on it's third motor at least. Most issues are probably dust related, so I'm basically asking how to clean this beast of a machine. Only issue that is not attributable to dust is a dead note, d2.


Currently three draw bars are dead to nearly dead, including 8' on upper b. Never use that one. Oddly enough, it seems to work, quietly, when second voice and almost any percussion tab is switched on. Draw bars have already been WD-40'd, No two draw bars sound at the same volume. I'm guessing I need to scrub the draw bars and possibly resolder a few wires. How do I go about getting to the draw bars, and what should I use to clean them?


Another issue is profound keyclick on each end of the manuals. Profound as in sometimes louder than the organ itself. Mr. Hack Repair man mentioned an internal busbar shift mechanism, though he only used it on the upper manual. Where is this mechanism, and is a similar system fitted to the lower manual? Worst comes to worst, how do I get to the busbars and what should I clean them with?


Largely unrelated, I love a quarter of the percussion tabs and hate the rest. If I have to dismantle the percussion section, I'd like to rewire the guitar and banjo tabs into second and third harmonics, preferably while incorporating some sort of soft/normal and fast/slow control. I can do without the entire cymbal/brush system, string bass system reiterate tab and control. Chimes and harp can go if need be, but I'd prefer to keep them. Glock, marimba, xylophone are the only things I actually like.

[indianajo]

You get into the drawbars for cleaning by taking the tab box apart. See bobmann107 video on u-tube. What is your serial number? Bob reports high serial number units have a grease on the drawbars that dried to soap, inhibiting current flow. I don't have that problem on my low serial number units. I sprayed out my drawbars with the plastic nozzle of a contact cleaner spray. I just took the top of the tab box off. Wood top comes off from the back two screws under the rail. metal tab box top comes off after the preamp covers come off, then a lot of screws, then pry back with a crowbar in ths slots.
The bus bar shifter is a large diameter screw on the high keys end at the back.
Key click is caused by the drying up of the electrolytic click filter and coupler caps on the preamps. Rather than unwire these to get to the back, I cut the old cap leads, made hooks of them, and hooked the new caps over the old leads. I replaced all electrolytics in #9574 except harp sustain, these preamp ones last. I used ones rated >3000 hours service life so that maybe I don't have to do this again in my lifetime. I had a little whistle on the high frequencies and added a 100 uf cap on the 24 v power supply at the high keys end to get rid of a 1 mhz oscillation on that line.
I don't like guitar and banjo attack. You can change those to twos and threes by moving the surplus harmonic wires from the NO contact to the pole contack. Speed of decay is in the percussion chassis, C105 on the transistor unit. I imagine the coupler and power supply caps in that unit are tired also if not replaced already. I tweaked the cut off and perc pots to where my glock sounds something like a Fender Rhodes electric piano. Useful for the intro to Free Bird, 0880000 lower versus piano upper.
Profound frequency imbalance was caused in my units by drying up of the electrolytic caps in the power supply, the power amp, the pedal/percussion amp, and the preamps. I started at the power supply and worked up in that order. Every couple of caps I put in made it sound better. I used CE and FP can caps on the first unit 9574, but those are $35 apiece. Taking the old can off cleanly is a ****. I usually rip the tabs off with pliers and unwind the can. I've started using 4 individual 450 v radial lead caps on cinch 53 or 56a terminal strips to replace the can caps. Long life Panasonic and Nichicon caps from newark, rubicon too in the smaller sizes. About $3 a section, plus $1 for the terminal strip, much cheaper than tall cans. Some extra 600 v wire is required, available in short lengths from triodeelectronic or tubesandmore the same places that sell the terminal strips. Everybody else's wire is 300 v rated or in 100' rolls at $.65 a foot for teflon.
I play some rock & roll arrangements and love the string bass feature to play the bass lines. Sounds to me just like a four string electric bass. Mine didn't work until I replaced the solenoid power caps in the PS, then was very soft until I got to the pedal (tube) chassis.
I intend to use the brush contact for midi encoding, but as my midi equipped synthesizer needs a new disk drive, I haven't bothered yet. It is the contact in the back. It would probably require removing the pedal/perc chassis again, the top, and tipping up the keyboard to get at it to add the wires. Right now they are all bussed both ways, drawbar and contacts to the brush board. The bus wire has to be removed and Individual wires have to be run to the midi encoder. I intend to double use those wires to strobe analog switches, to feed in sawtooth waves for formant stops available on other organs like the X66. Also filtering an 8' wave to half wave and make an allen clone principal stop is in the future. Analog switches are about $.60 for four in an IC but making the board is beyond my skill at this point. I intend to make sawtooth waves with shift register IC's counting down the 2' wave and analog current summing.
I haven't cleaned or shifted my busbars. If I don't play frequently on 9574 Eb6 percussion doesn't work, I'm thinking to shifting to see if I can clear that up. All other harmonics work reliably if I play often enough to knock the dust off. I haven't removed or cleaned my bus bars. I haven't addressed any foam issue, either.
Don't forget to replace the power cord under the power transformer where the insulation falls off. Some wire removal and replacement is required to do the job cleanly with a 130 W iron or butane one. Dont' forget to replace the motor cap, mine bulged and nearly exploded on 2211 the second time I turned it on. The one on 9574 burned the yellow wire down to one strand in 1997, the sleazy dealer tech didnt insulate or replace the wire, just the cap. Use 90 deg insulated flag terminals from dorman at the auto supply and a genilec 3.3 uf 330 v film motor cap from newark or an epcos film cap from mouser. Film should last forever. I used film for some of the caps up in the preamps and CPO ceramic for others, about $5 apiece for AVX 50v gold ceramic. Lower voltage ceramic would be too non-linear. Don't forget the power on silence e-cap in the tab box if your high serial unit has one.
I listened to Reader's Digest Pop Organ Varieties last night, Bob Benson on Baldwin and Richard Wayne on Lowrey. I'm so glad I didn't buy either one of those. I haven't heard anything that bad since the organ radio the duck played continually in Wallace & Grommet's The Wrong Trousers. The H100 can be made to sound crisp and authentic, not sappy.

[Stanislao]

Serial number 23989. Because this is a 1969, there are no electrolytic capacitors in the organ. I think all the capacitors are film type, maybe the odd ceramic, never seen an electrolytic capacitor.


Can you elaborate further on the modifications to the guitar and banjo tabs, as well as the speed of decay on the percussion chassis?


Does the bus bar shifter work on both manuals or are there two shifters?

[Jaim]

There should be electrolytic caps in the PS, power amp and preamp boards. There are 2 bus bar shifters located on the left side (looking from the back) - large brass screw in the manual cover.

Jim

[indianajo]

Also the pedal and percussion chassis on the back of the keyboard. Also the infamous PUR silence cap in the tab box on high serial #, not on any schematic diagram I've seen.
On the schematic diagrram, each cap with a curved and straight plate is electrolytic. All caps with plus on one end, minus in balls pointing to one lead, or cans with circle squares and triangles pointing out various sections, are electrotytic. Tantalums have a red end. Couple of those in the transistor percussion chassis, I bought one from Bobmann salvage. 6 of the 7 tantalums in H100s have been trash.
I replaced one of the electrotlyc 2 gang caps on the power supply with 47 uf 1000 vdc film ones on #9574. Each section was 2.5" diameter, 4" tall, and weighed about 2 lb. $14 each. It took a separate chassis to house two of these forever caps. With that motor quality low ESR though, great punchy string bass results.
See this thread about replacing $35 can caps with 2 or 4 $3 sections of extended service liveradial lead caps: http://www.diyaudio.com/forums/tubes...ube-amp-3.html