Hammond X77 Owners Corner

[bnelson218]

Finally, after all the complaining about the X77 and its design problems...someone is actually offering some HELP!!
Hi there, I own a Pre 1969 X77 with X77L tone cabinet, and after having owned many other Hammonds, I am here to tell you that this is the last of the great Hammond tonewheel organs that with some modification, can ACTUALLY OUT PERFORM THe IMMORTAL B3!!!!

Points to consider:
-This instrument looks Gorgeous (Funky...not like a church organ) in your living room.
-X77 contains MODERN electronic components, so re-capping etc is not required.
-X77 is ALL solid state, so electronic parts are easy to get.
-X77L leslie tone cabinet is a 200 watt 4 channel beast!
-No "Gooey Foam Problem" like many of the 60's Hammonds had.
-Console comes appart easilly, and the many circuit boards are easy to get at.
-X77 has the funky B3 percussion built in...but needs an adjustment to tighten it up.
-ALL HUMM and FIREWORKS problems can be TOTALLY ELLIMINATED!
-Learn how to ADD the ORIGIONAL Hammond B3 vibrato scanner (C3 chorus) to the X77.
-Learn how to mofify leslie X77L to function like model 122 on steroids!
Should there be enough interest in this I will provide a website with MP3s to demonstrate EXACTLY how EXCITING this instrument can be

Sincerely
Don Cake (AKA Screemin Keys)

Has anyone ever heard from this gentleman? He seems to have disappeared...

[innerfire]

It spins when attached, is it supposed to? How do i fix it? Thanks.

[Wes]

The whole point of Mercotac is to spin. If it is spinning, it does not need fixing. If it does not spin, it is broken and must be replaced.

[Admin]

Has anyone ever heard from this gentleman? He seems to have disappeared...

You can view the profile of any member to see when they were last on the Forum. This guy's been gone since May 2010. Talked a good game, but never followed up with results.

[enor]

"-X77 contains MODERN electronic components, so re-capping etc is not required.
-X77 is ALL solid state, so electronic parts are easy to get."

The above quotes show without a doubt that he was in over his head... no wonder he didn't follow up with results.

[Wes]

What he said was completely true ..... in 1980 :D

[bnelson218]

Yes, I agree, it was a lot of big talk, however, it did inspire me to research all his proposals and ideas. I started my X77-B rebuild in 2011 and am still laboring over it. The money's limited on disability but I manage to get a little done each month. There is a new control panel, the integration of the Trek II SSP-3 preamp, the velocity sensitive MIDI on the upper manual (that alone took 2 years to develop. Like Edison, I've discovered lots of ways NOT to do something), and 22 circuit boards to design and build. All in all, there are roughly 1500 components in the organ. Hopefully, by spring 2017 I'll have some results for you all to see and hear. I just hope the friggin' thing works. :)

[innerfire]

Does anyone know of this white funnel gets oil?
It seems my horns aren't sounding also? Hmm any one know?

[Admin]

yes. The white funnels get oil. There should be a card in the organ saying how much.

The rotor horns will only sound when the Leslie tabs are down.

[innerfire]

Thank you for all you guidence, I've only seen one funnel in there does that sound correct? Also, I'm understanding the mercotec fitting, does it have a berring on the bottom side of it? Mine is frozen if so, or does it get just a little graphite, or oil to help. It wants to twist the connecting wires and gets staticy .. do i need a new one, it will work but seems like the wires need to be secured to the bass speaker or something. Thanks again,,!

[geoelectro]

There should be two oil funnels. One is kinda hidden under the preset panel.

The Mercotac is two pieces formed together. The top spins against the bottom. There should be no tension against the connector. Sometimes, you can force it to spin where it will loosen up and work. Also shaking it can help with the static. It can spread the mercury around inside. Otherwise, replace it.

Geo

[bnelson218]

I've finally been able to put some money into my X77-B rebuild project and get a few PC boards made.
The first one is the Kick Switch board. There is a momentary switch on the left side of the expression pedal and this board allows me to select from 6 different functions for that switch to control.


The next 2 boards are the MIDI Keyers which send Key-On and Key-Off data to the Arduino processor. Additionally, these boards also provide the trigger signal for the Trek II, SSP-3 preamp's percussion circuit.


These boards haven't been tested yet because I ran out of a few components and had to order more. But the Kick Switch board is complete and the onboard sequencer work's great.

I'm waiting on the boards for the organ's redesigned percussion system and will show them soon.

[Admin]

Impressive looking boards.

[MihevicB3]

Nice layout and work on the boards. I am curious as to what the 6 functions are that you can control from the expression pedal Kick Switch? Also do you have to predetermine the function and have it selectable at the board or are the 6 functions changeable from the console?

John M.

[bnelson218]

Thanks Admin!

- - - Updated - - -

Hi John,
Some of the functions are hard wired. For instance, #1 is for the Midi sustain, #2 is in/out control for the Chord Comp feature (kind'a like Lowrey's AOC), #3 is in/out control for MIDI channel 1, which is hard wired to the internally installed Roland JV-880 synth module, #4 is in/out for MIDI channel 2, which is a 5-pin DIN mounted on the organ's accessory panel, and #5 and 6 are 1/4" jacks also mounted on the acc panel. There are 2 jacks for each, one is for a normally open contact and the other for normally closed so that a variety of effects units or drum machines can be accommodated. The controls for the kick switch are mounted on the lower right cheek block...

(The other panel shown is the upper right block used for power.)
Here's the schematic for the kick switch...

The momentary button, SWM1, cycles the 4017 sequencer chip which steps through the 6, 4PDT relays. The 555 is for the debounce circuit.
I use expresspcb.com's free schematic and pcb design programs for everything, and futurlec.com produces the pc boards. If you're interested in anything else let me know.