Help with Hammond Colonnad (a.k.a. model 333172)

[sltjensen]

Help! I'm in the US military stationed in Korea and need help trying to fix a Hammond Colonnade (333172) organ. This organ belonged to my father who passed away and I'd like to get it back working. Recently, I moved to Korea and was able to get the organ moved out of storage to join me at this assignment. A few years ago, a mouse got into the wiring and chewed through several wires on the center, lower part of the cabinet. Most of the damage was done to the wiring leading to the volume pedal. When I turned in on in Korea, it didn't make a sound. However, upon opening up the organ, soldered the damaged wires back together and put shrink tubing around the repair. When I turned it back on. Bingo! I had sound. Upper keys worked (albeit a slightly lower volume than the lower), lower keys worked, pedals worked! I though I had this licked. Turned it off, then back on... now I can get the percussion to work, but not much else. Pedals trigger percussion. Lower keys trigger some percussion and background rhythms. Upper keys do nothing. I have some electronics experience, but could use help with test points, etc. Appreciate anythihng you can help with. Any manuals, schematics, test points, all would help.

Thanks for your consideration.

[andyg]

The usual first step we get all LSI Hammond owners to go through is to unplug, clean and reseat every internal connector. You can use Caig DeOxit on the connectors. Problems with these connectors are the root cause of many a problem in these Hammonds, we tend to call it 'LSI Disease'. Even if it doesn't cure the problems you have right now (though it might well do so) it's good preventitive maintenance.

See what you've got working when you done the cleanup.

[indianajo]

This organ has PMOS and CMOS parts in it, so do any work at high room humidity or wear a static collar connecting your wrist to the chassis through a resistor. This tool is available from electronic supply houses. Don't pull or replace any connectors without it at low humidity. Andy lives near the sea, so it won't be a problem in his neighborhood, but can be in the hills of Korea.
A problem with any old organ after 1955 is that the electrolytic capacitors dry out through the deteriorated rubber seals. Frequently people will start playing one that hasn't been played in years, and it works fine for a few hours or days. Then the heat of use dries the water out and the caps short or go low capacity.
If this is similar to the 246xxx Aurora I have some schematics for, then the tone generator works on different power supplies and PWBs than the percussion. The generator PWB has 10 40 pin DIP IC"s, a 16 pin divider IC, and some smaller op amps. This had -15V coming in J44 pins 14,15, with logic common being J44 1-6 and J42 and 43 pins 1-4.
The logic PWB has -5 V coming in J130 ppins 4,3, and -14 coming in pins 1&2 . Logic common is J130 pins 5 & 6.
The fatter wires to connectors tend to be the ones carrying power supplies. Electrolytic caps are plastic covered aluminum cans with a plus near one lead, although some tantalum ones (also with a plus or red end) look like Peanut M&M's.
An Elegante has a similar TG IC's but different PWB numbers, so your J numbers may vary.
A tutorial on changing electrolytic caps in transistor organs is http://www.organforum.com/forums/sho...146#post280146
Organ service of countryside, IL, may have the schematic diagram. If more economical Jan Girardot has it, his list can be accessed through the "for sale music and accessories" forum below.
Be aware, on a couple of Aurora's, I suspected that C1-C8 on the demux PWB with the 4052's, dried up and caused damage either to the 4052's or the PMOS roms on the gen PWB. The member owning the organ gave up repair without disproving my theory. These should be ordered (at about $.10 each) with any other parts, as if the PMOS roms blow up the only way to get them is buy another organ.
I find farnell.com has good service in the US and does not sell counterfeit parts, so in a second world country I would recommend them. They have outlets around the world.

[sltjensen]

Than you Andy. I appreciate the suggestion.

- - - Updated - - -

Indiana Jo, I really appreciate the heads up about the CMOS. I haven't worn a statis strap in years and wouldn't have thought about it. Humidity has been pretty high here lately with few days (if any) less than 50%. Is there a visual way to tell if the caps have gone bad? I have a multimeter, but it doesn't have a capaciter reading on it. I haven't seen any dip switches in the organ yet. But, I need to spend some time really looking at all the parts. Power supply appears to be in the bottom right and what I believe is called a Leslie box installed in a white styrofoam box on the left. I figured out how to open the whole thing yesterday, but it doesn't have as much hand room as I would have expected in the top. But, as least the parts are hinged to open.

Thanks for the info and the suggestion of Farnell.com.

[indianajo]

As far as testing your caps, farnell has a nice meter that checks caps up to 10000 uf and shows ESR, for $150. I check electrolytic caps by looking at the calender. If your 1975 red line tires on your 1970 Mustang hold the correct amount of air, is it safe to take them out on the freeway? The caps are sealed with the same rubber, or probably *****ier.
After doing the reseat connectors exercise Andy recommends, I would check power supplies to see if they are correct. If not, caps are the usually the cause after 35 years but not always the only damage. Shorted caps can blow rectifiers, or voltage regulators or pass transistors. 78xx voltage regulators are a bit dicey, anyway.
The C1-C8 on demux I wouldn't measure, not unless you want to burn hours learning how to play this organ then have the PMOS sine wave table ROMs blow up in an unrepairable event. I'd spend the $2 they cost and the 5 hours it might take to change them (from a cold start). New organs with new electrolytic caps with this much capability, like a Roland AT900 or something, are >$10000. So I see it as worth doing, even though the B3 snobs look down at their noses at any organ that has more sounds than 08800000 Leslie fast.
A total electrolytic recap should be under $100 parts, $75 tools, and maybe 200 hours unless your more productive than me. (Many military people are amazing that way). You could also hire a radar or avionics tech to do the work, probably. Check the base electronics hobby shop for the talented.