Hi,
I have installed the new display and it works well, a big improvement. I had a few small problems when fitting it so I will mention them here -
The footprint of the new display (I used) was much smaller vertically than the original display, so I could not use all the original mounting screws. I decided to just mount it using the top screws only. This works ok and the display bottom edge is resting on the lower screws so it does not move about.
One thing about the mounting screws - they are fitted loosely through the front panel from the front side, but behind the stick-on panel overlay, which holds them in place. When I was loosening and tightening the retaining nuts on these screws, I had to apply pressure to the front panel where the screw heads are to stop them from turning.
When I fitted the new display and first powered it up, I realised it was upside down! - the connections are on the top edge, on the original display they are on the bottom edge.
The connectors on the new display are numbered 1-16, this seems to be a standardised connection for this type of display. You need to desolder the ribbon cable from the original display and solder it in the same positions on the new display (connections 1-14 in exactly the same order as the old display) This leaves connections 15 & 16 free, which are for the led backlight (15 is 5v and 16 is ground/0v) You can obtain these voltages from the main pcb nearby - resistor R7 is connected accross the 5v power rail so all you have to do is solder a wire to each side of R7 (the end of R7 nearest to the front panel is +5v) and connect the wires to 15 and 16 on the LCD.
If you unplug the LCD ribbon connector from the main board, make a note of which way round it goes.
The LCD contrast needs to be adjusted - there is a small trimmer on the main pcb just behind the display - I had to turn it fully anticlockwise to get an acceptable contrast - it is ok now, but could be better. The reason for this is that the original display uses a negative voltage for contrast adjustment, but the new one I used needs a positive voltage. I will probably modify this so it gives the proper range of adjustment, but for now it is usable as is.
Hope that info is of some help if you decide to change the LCD, it is definitely worthwhile.
I will try and get some photos uploaded to the file section soon.
Cheers, vout
--- In Simmons_Drums@yahoogroups.com, "teknikfourteen" <teknik14@...> wrote:
>
> How is the MTM LCD Display project coming along?
> :-)
>
> Cheers
> Teknik14
>
>
> --- In Simmons_Drums@yahoogroups.com, vout@ wrote:
> >
> > Hi,
> >
> > I recently bought an MTM and I am also looking to fit a backlit display. The service manual shows that the display is a standard HD44780 controller type - these are available everywhere for a few pounds. There are a couple of things to consider - the mounting holes on most current displays seem to be slightly further apart (1-2mm horizontally) a bit of filing should sort that. Also you need to feed 5v to the backlight - usually pins 15/16 on the display or there may be a separate backlight connection. I've just ordered a cheap display from ebay (£1.50 including delivery!), we'll see how it goes.
> >
> > Cheers, vout
> >
> > --- In Simmons_Drums@yahoogroups.com, "teknikfourteen" <teknik14@> wrote:
> > >
> > > Hi all..
> > >
> > > Re MTM:
> > >
> > > I am in the process of cosmetically reconditioning a working MTM:
> > >
> > > 1. Does anyone know of a suitable replacement part # and source that would allow replacing the current LCD "dark" display with a new back-lit one? Some MTM's had back-lit displays, this one does not.
> > > Would the display that's available for the Portakit from a Canadian supplier be suitable?
> > > I don't have access to MTM schematics.. :-(
> > >
> > > 2. Does anyone have dead MTM for sale or parts available? I'm looking for:
> > > - set of Rack Ears
> > > - front panel knob for the "Trig out" pot
> > >
> > > I just had the case stripped and powder coated and the unit looks fantastic except for the missing knob (bought unit from eBay in this condition).
> > >
> > > Cheers :-)
> > > Teknik14
> > >
> >
>