Keyboardpartner-Forum

Hello everybody,
I apologise for posting in English, my knowledge of German is very limited.

I am just about to place my order for a HX3 board and would be grateful of some advice regarding additional parts.

I have a full set of 38 genuine hammond drawbars but I am unsure if these interface directly with the main board or require an additional scan board.

It is my intention to use 2 x fatar tp80. I believe that a single fatar scan 61 will suffice for both manuals, is this correct?

Also, I would like to add the familiar inverted preset keys to each manual, but am unclear as to which board will allow me to set them up to behave like on
an original hammond. (I understand that I would need to modify the keys switches)

Bass pedals will be added at a later date.

Beyond what I have described above all that remains is to add the usual rocker switches as per b3/c3 and a half moon for the Leslie simulation.

I have no desire at this point to add any additional knobs or switches beyond what can be found on an original console. Any advice regarding the above will be welcomed as well as anything I may have overlooked. Thank you for reading.

hi,
Let me begin first with the drawbars You want to use.
I don´t know which kind of drawbars they are.
case a ) Drawbars from organs like B 3 , A 100 or C3 types
case b ) Drawbars from smaller Hammonds like T 500 or Aurora series

Drawbars of case a) never have any "resistors" between the step lines drawbar position 0 to 8
Such organs use the " matching transformer " . Every drawbar set equal if from upper or lower manual or pedal
are connected in parallel to this "matching transformer". All 38 drawbars buildt then a complete "unit"

Drawbars of case b) still have a resistor array at one end of drawbar set. Each drawbar set has such an array

So if such a unit like case a) is used You will have to add the resistors.

In case b) you can use each drawbar set same way as in smaller Hammonds
Busbar at ZERO is connected to GND and busbar at level "8" is connected to 3,3 volt same way as in using the HX3 drawbars

FATAR KEYS :

You need only one board FATARSCAN 2 for connecting both manuals ( each with 61 keys ) even when first only one keyboard in use.

If there are inverted keys also wanted there are two ways to realize.
1) 6 octave FATAR keys with one octave inverted. In this case You need rubbercontacts for 5 octaves because of the matrix of rubbercontacts. For the inverted preset keys You need a sheet of one octave rubber contacts EXTRA

2) normal 5 octave FATAR keys and a cutted part of 12 keys of a inverted manual.
For this option You have to order two normal waterfall 5 ovtave manuals and one manual ( 4 or 5 octave ) with inverted keys.
Separeted two units of 12 keys will then be Your preset keys.
The rubber contacts of these presets must be preparated for using at presets with thin cables direct connected to the rubber contacts.
The board to connect them to the HX3 is the preset 12 - 2 for both manuals

If wanted to realize the presets as "latching" ones You have to use the mechanic like in real Hammond
If they are latching ones You must declare them in REMOTE SOFTWARE as latching ones. Otherwise simply push buttons with LEDs
For realize as latching ones there is much mechanicly work to do to realize this. Not easy but possible.

3) another option for latching presets is using some units from HAMMOND B 3000 . In this case You only have to do some
cosmetics at front of the black keys to change the "look" to waterfall design.

Thank you very much for your great response Happyfreddy.

You have certainly cleared things up for me.

The drawbar set I have acquired is from an A100, so I will add resistors as you suggest.

For the preset keys I intend to use 2 octaves from an inverted tp80, which I intend to convert to a latching type using a magnetic key latch which I have been working on for this project, (something I will be happy to share here if it proves effective). The bubble contacts will be replaced with a more suitable solution for this purpose. The remaining 3 octaves will be utilised in another project.

Thank you again for taking the time to respond in such detail, I look forward to getting started on my build and I'm sure our paths may cross again in the forum.

hi,
again back to how to realize preset keys with rubber boards ( length of 12 keys )

When You have the sheet of printed rubbercontact board You have to "unplug" some rubbercontacts
to see how they are made , specially the routing
Rubber contacts principially are made of a pair of "routed fingers" and the contact area is plated golden.
The rubbercontacts itself are of dynamic kind so with the key You close thes pair of contacts one after another.
The first rubbercontacts are connected at one end together. You have to find out which of the two is realized
in this way. The second "finger" will run to one plugpin of the matrix.
The matrix itself is for preset contacts never needed so You have than to separate this.
The result so must be
one common contact connected to GND
12 separate contacts for the wanted 12 preset keys.
So sometimes ( case of used sheet of rubbercontact board ) it is necessary to cut layout lines and to connect
some layout lines.
The whole wiring must be done with the thinnest wire You can find.
Best way is the use of some thin isoltated coil wires. The reason of thin wires is the fact that You
sometimes must go under the rubber itself to realize the needed connections

Because the second finger rubbercontact is connected same way for the second dynamic contact it is a good idea
to connect the two rubber contacts of each key in PARALLEL. It´s not needed but better ..........
If only one contact in use chose the first one being closed by key

In final result You must have than a terminal with 13 connectors :
TWO for GND and the 12 needed keys ... ie use a 14 pole flatcable plug mounted directly under the rubber board.

For connection to preset 12- 2 board than use a little "Adapter board selfmade " to needed board connection

Thanks again.

I have quite a bit of experience with repair and modification of keyed's, but still I always welcome new knowledge and solutions.
The approach that you suggest is one I hadn't thought of, and it seems it may be a more convenient solution. I look forward to experimenting with this.

Best wishes Happyfreddy.

The problem using 6 octave FATAR keyboards is that the matrix of rubbercontacts is different from those
of 5 octave manuals. For using FATAR keyboards You need the matrix of the 5 octave keys,
ie the rubbercontact boards of the 5 octave manual.
Waterfall keys and normal keyboards ( overhanging keys ) have the same rubbercontact board.
Changing the lower octave keys to inverted ones is simple.
Some user here have realized this by using normal 5 octave keys and added one octave of an extra inverted keyboard.
In this case You must cut it carefully with very thin cutting tool / saw. The problem zone is the back mechanical bearing
realized by a plastik profile tip. You only have to cut the distance of 1 mm between the keys. Second problem is the included metal plate of the manual body which has to be cut too.
So simpliest - but not cheapest - way is to use 6 octave manuals and the rubber boards of 5 octave manuals.
The rubbercontact board of the 6 octave then can be cut into needed preset keys.
Because You never can buy single rubbercontact boards You have to order complete manuals.