If you are going to order the MCU update you might as well go the whole route and order the Conrad gears (with nice 12v DC motors that can be used for other things... like electronic focusing etc.), the 5m cable to attach the scope to your computer for firmware updates, electronic control etc. and the hand-controller update which, in my humble opinion is a must-have.
I didn't take any pictures again. The images shown are from Anand Rajiva's web-pages which can be viewd at http://eq6.update.rajiva.de.
To install the Rajiva Motor Control Unit (MCU) Upddate
You will be handling electronics. Use standard anti-static procedures.
- Remove the 6 screws on the plastic motor cover and remove.
- Remove the 4 screws on the top cover and remove it.
- Make a connector template
- Rajiva didn't ship a template with his connector. Take the connector and put it face down on a sheet
of paper. Trace around the 'D' shell with a sharp pencil. Then push the pencil through the holes to locate
the screws. Tape this to the top cover ON THE SIDE OPPOSITE THE MOTOR COVER. A better way to go would be to
take the end-plate off of a computer board with a joystick port and use it as a template. That way you have
a solid 'stop' in place and can cut the hole correctly.
- Use a drill and file (or Dremel tool) to cut out the hole for the connector.
-
Be careful as you go and 'creep up' on the actual size. The tighter the fit the nicer it will look. I used a drill
and a Dremel tool and came pretty darned close to a perfect fit in about 15 minutes.
The newer versions of the MCU Update board have a large capacitor 'hanging' off the top of the board. If you place the cable for the 15-pin connector so that it runs over top of the capacitor there is a good chance that you'll break the capacitor connections. It's happened to me twice. Make the hole for the connector so that the cable runs close to the power connector and the cable connector is as far towards the front of the mount as possible.
- Remove the motors
-
Each motor is held in place by 4 screws on the mounting plate. Remove the connectors on the electronics board (they're
keyed so you can't put them back on backwards. Just note the power plug and the Dec motor plug. Don't get them mixed up.
They have different wire colour schemes so write it down. Now remove the motors.
- Remove the MCU
-
Looking down into the 'guts' when the motors are out you'll see two silver screws; one on each side of the MCU that you
will have to remove. Once those are out the MCU slides out nicely.
- Remove the old CPU
-
The CPU is the big flat chip on the board. Just put a small jeweler's screwdriver or Xacto knife under the edges and
'wiggle' it out. Note the orientation of the chip. One corner has a 'dimple' in it. The upgrade board goes in with the
dimple on it's chip in the same orientation.
- Plug in the MCU Update board
-
Test fit the board, make sure it's not touching anything else. You may have to CAREFULLY bend over a capacitor and a
silver oscillator. Then position the board so that ALL of the pins meet a hole in the original chip's socket and push
down evenly til it 'seats'. Then check both edges. There's another chip under the board toward you to the right of the
new CPU chip on the Synta board. Look under to make sure you have no pins or solder touching anything down there. If you
think you do then slightly lift the MCU Update board a 1/16 of an inch (or less). A better solution is to cut some thin,
fairly stiff plastic sheet the same size as the MCU Update board then cut two slots in it for the legs to go through. Put
this 'isolator' between the MCU Update board and the original board.
- Replace the MCU.
-
Slide it in and put the 2 silver screws back in place.
- Re-connect the power/motor connectors.
-
Plug all the connectors back in. Let the ribbon cable for the external connector go between the Dec motor wires and the
MCU.
- Install the external connector
-
Put the external 15-pin connector in place in the top cover and secure it.
Note
I originally placed the connector improperly and twice broke the 'Goldcap' off from the MCU Update board. If you've alread improperly placed the connector here is a fix. Expand the original connector hole forward far enough to move the connector and build a plate to mount the connector properly. This will leave a large hole which you can cover. Make the cover plate out of a blind end-plate from a computer. Position the hole properly on the plate and then drill a hole forward to secure the front end of the plate. Expand the hole in the HEQ5 top cover enough so that the connector will fit through but small enough that your new plate covers it. Place epoxy around the edges so that the new plate seals and screw it in place then clean off any epoxy with alcohol. Let it set then screw in the connector and replace the top cover.
- Replace the covers
Updating the hand controller is a 5 minute job and only needs some care in the orientation and handling of the new chip. Use standard anti-static precautions.
- Remove the 4 screws holding the top plate on
- Lift the top plate. The buttons are snapped into place so some force may be necessary. Don't pry; it's plastic.
- Remove the button PCB board by removing the two small screws. Then flip it back
- Using your Xacto knife lift out the original CPU as you did with the CPU in the MCU. It's a lot smaller so just
take your time and don't put a lot of force on it. Check the orientation of the 'dimple' as on the MCU chip.
- Plug in the new chip. Make sure it's oriented right and that all the pins actually go into a slot. They can bend under
so take care and watch.
- Screw back on the button PCB
- Screw back on the top cover
- Replace the buttons.
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