This is a replacement for the PC board behind the LX200 Power Panel. It is a newly-designed circuit board replacement for the original in the 8", 10", and 12" Meade LX200 "Classic" telescope.
This circuit improves on the original by using a high-side current measurement approach that does not put additional resistance in the ground path. It will also emulate the Hand Controller boot sequence, if no hand controller is present.
Redesigned current measurement with clean grounding.
Auto-detecting boot emulation if hand controller is not attached at start-up.
Various other minor improvements (see below for more).
Easy installation with no soldering needed.
Priced at only
A PDF document with instructions for installing in the LX200 is available here: installation.pdf
Note that this product does NOT include the fuse or coin battery. The new board requires exactly the same two parts; they can be simply transferred from the old board.
This design improves upon the original:
Measurement of current for the LED bar display is done using a specialized current sense amplifier and low 0.01-ohm sense resistor (10X lower than the original). This resistor is on the positive supply rail rather than in series with ground, to further improve ground noise. Current handling is upgraded by using larger traces for power signals such as the declination motor assembly's power, ground and motor drive, along with a robust ground plane. The 2200 uF capacitor is moved to a safer electrical site, preventing the situation described in this forum post
An additional feature is the ability to emulate the hand controller's boot-up sequence so that the telescope can operate without the original hand controller, using, for example, PC software communicating through one of the the RS-232 ports. The board senses whether the hand controller is present, and if not, takes over the initial handshake with the telescope, allowing RS-232 control of the scope. The current monitoring LED bars are used to communicate the status of this handshake before reverting back to current display.
We are happy to provide more design details via email.
To order, or for questions, please contact us at firstname.lastname@example.org.
We ship internationally.