Handy TG Number Guide

[Bobmann]

I made this guide to help identify terminal numbers on the TG easily.
If I need to recap a TG, the terminals need to be identified so that I can document the outputs.
Also, if I need to find a particular terminal that corresponds to a tone, I need to know the numbers.
So, I came up with this aid.
NOTE that this is for a majority of TG, but not the older sequentially wired ones.
There are 4 cards that correspond to the 4 sections of terminal strip. It takes a second to put the card over the terminals to identify them.
This also identifies which terminals are not wired to either pedal or keyboard wire harness.

I tried to upload the file here, it is a .oxpx format which should be able to be opened in any windows computer, but I got an error message that uploading this format was forbidden. I had to save it in that format, because for some reason any other format, like ,pdf would not print without changing the actual size and this needs to print exactly 1:1 to maintain spacing. It was drawn in AutoCad, and there are very few options to save in any format other than .dwg, and that format is not easily translated into any other format easily or accurately.
If anyone wants a copy of this file, just send me a PM and I would be happy to share it with you. Worst case, I am also happy to mail an actual paper copy, just like the old days

Bob

[Admin]

I think you mean oxps not oxpx. Frankly, I've never heard of this format, but apparently it's a superset of Microsoft's .xps format that I am familiar with. .oxps files can be opened in MS Word under both Windows and OSX or viewed on current Windows versions with Microsoft's XPS viewer.

I can add upload support for this filetype, but I need to have an idea of typical file sizes in order to do so.

[Bobmann]

You are indeed correct, it is .oxps
This file is 65kb, not very big.

Bob

[Admin]

Thanks. I've added attachment support for xps and oxps file formats. You should be able to upload those files as attachments now. If one is on a Mac, the aforementioned MS Word will open these files, and there are also third party apps for Macs and Linux. Support for these filetypes is baked into Windows beginning with Windows 7 through the XPS viewer app, as well as MS Word.

[Bobmann]

Attached is the file for the number cards.
Note that there is a reference dimension that needs to be verified. If the length is not 7 1/8" the tabs will not line up.
It should work if you just double click on the file after downloading.
When I opened it in Word, for some reason the cards were not the right size.

I print this out on card stock, and cut out with my X-acto.

Bob

[Drummer55]

Very cool and useful indeed. Thank you so much!!! This will save time of looking it up on the computer, then back to the organ and repeating... Awesome.

[samibe]

If you made the drawing in autocad, can't you print a pdf? If it's large enough that it needs to be printed on multiple sheets of paper, can you set up the veiwports in the "paper space" to print at the correct scale? All of my final autocad drawings are sent as pdfs at this point (though I seldom use autocad anymore).

[Ceebo66]

Hey Bobmann, that is a fantastic rig. It’s great there are still folks passionate about restoring things like the Hammonds that are works of art and marvels of technology. I just entered the Hammond realm I finally found a m111 on Craigslist for $75 in driving distance and got a bonus m101 for an additional $75. Fella needed money and room. Both actually really great condition and working. We’re stored properly. Any way when I saw this post I figure you may be just the right guy to help. One has two keys have no tone on one drawbar when I go through the test of each key on each drawbar that I learned on YouTube . I have no clue where to check for the remedy. I work on repairing many other electrical items old and new. Been getting into some tube gear repair for a few years so I know a little troubleshooting. Thanks for any direction. Chuck

[Bodie]

This chart looks good. I did a re-cap on my TG, got the kit from Goff. However on my travels I wondered if it was such a good idea because it affects a number of parameters for each tonewheel. I then found charts of each tonewheel output, altering the output level of a single tonewheel (by changing the cap) affects the overall tone of the organ. I've seen a number of charts people have made by testing their organ. This leads me to, is there any published "calibration" data from Hammond that specify what the output from each tonewheel should be? Nerdy I know.

Below should be a screen grab of audio taken from the preamp (not individual TGs) of my C3 - I pulled the 16' bar to see the lowest octave notes and the 4' bar to see the upper octave notes (before any foldback). Marked with a *

[kziss]

is there any published "calibration" data from Hammond that specify what the output from each tonewheel should be?

Hi Bodie.
The Hammond organ company never released the official factory intended tonewheel generator (TG) output levels as measured directly from the TG output terminal strip. The now deceased Hammond technicians Sal Azzarelli and Mike Fulk wrote that they had factory documentation about this, but they never released this information.

Sadly Mike Fulk died in his trailer home fire and it is likely that the boxes of factory documentation that he had in the trailer or in the adjoining car port may have been destroyed in the fire, or by the fire hose water, or discarded with other ruined things in the cleanup that would have been done after the fire.
Sal Azzarelli wrote that he was intending to write a book which would reveal a lot of interesting Hammond factory information, but he died before he was able to write the book.

The Hammond service manual for the A/B/C/D/RT organs does have a chart titled "Table V Generator Output Voltages" which shows the output levels of the TG notes measured through the AO28 preamp GG output levels whilst each TG note is connected to one of the preset panel busbars with a clip lead.

There is also a very old output curve graph from 1949 which is titled as "Approximate Output Voltage Readings Of Organ Generator Frequencies 1 to 91" which shows the TG output levels measured through the speaker output terminals of the power amplifier (Hammond tone cabinet) whilst the appropriate drawbar is pulled out and the appropriate keys are played.

The service manual chart and the old 1949 output curve graph are useful to some degree, but the resulting readings are dependent on the preamp or the power amplifier which colour the frequency response, but what we would really want to know is what the factory intended TG output levels directly from the TG output terminal strip should be.

In the absence of any official factory data, we can see the approximate factory TG output curve specs by observing the similarities in the output curves of the measured recapped pre-1964 TG's, and the red mylar capped post 1964 TG's

I have compiled into my TG data spreadsheet the measured output levels of over one hundred TG's including all the TG's which I have measured, and also the measured TG output levels data which dozens of other people have sent me over the years, and all this TG output levels data more or less indicates what the approximate factory TG output levels were as well as the changes made to the TG output curves over the decades.
All the best.
Kon..

[Bodie]

Thanks for the info Kon. Mine had light brown/fawn waxy caps on the TG, I still have them. I saw a vid on YT that showed the person in Ham. Calibration/Test selecting caps for the TGs and trays of caps with small value differences. The person seemed to be trying different cap values to get the desired output. I did this on my TG as an experiment and yes the outputs do variy significantly versus nF. Was someting like 22nF+ selector switch with 1nF, 4n7, 10n, 47nF as positions, yes a bit too geeky.

I'm sorry to hear about the two former H engineers, it's one of those things in life where, have info, collect it all up and have it ready to distribute! As always, that final day causes so much valuable information to be lost from all kinds of people.

[Bodie]

I found this on tonewheel capacitor replacement and calibration, our very own Kon Z gets a mention (thanks for the data). This is exactly the information I was looking for.
http://www.stefanv.com/electronics/h...apacitors.html