daryl bane
Titanium
- Joined
- Mar 12, 2002
- Location
- East Texas
I am doing this for posterity as detailed info about these units seems to be hard to get. Sorry for the stream of conscience format. This primarily is about the read heads and what I have discovered so far. The unit themselves are really pretty simple. You can access the internal assy. removing four screws on the side of the unit and then both sides come off. There is a pendulum suspended by 5 tiny beryllium wires. These are quite robust and breakage is rare. There is a bar (armature) that sits on the pendulum between two transducer coils. You can check these coils with an ohmmeter, to make sure there is equal continuity between them. Use the smallest voltage on your meter and do it quickly, or you can damage the coils. There are two micrometer knobs that are attached to a spring loaded bar that the whole pendulum assy. is bolted to. You can screw the two knobs all the way up until the bar contacts the two ground pins and can determine zero to the base/frame. The knob scales can be adjusted by loosening the two screws on the top of each knob to adjust the scale. There is a threaded radiused post on the bottom that keeps the unit centered due to being sprung, this also has a locking screw. This post is adjusted that when you screw the micrometer knobs all the way down, the unit rests on two rubber pads and this post, so that the wires are now out of tension and not under pressure from transport. The pendulum unit has a tiny silicon damping blob located on the bottom of the pendulum assy. and this blob is sandwiched between the movable assy. and the mounting base. There is a clear plastic threaded plug that screws into this base, and with a loupe you can see when the radiused front of the plug just touches the silicone blob. There is a copper tension arm that goes on the top of the plug to keep it from moving. There are threaded stops on either side of the assy. to limit back and forth pendulum movement. There are threaded holes on each side of the pendulum assy, that are accessible thru holes in the main housing via rubber plugs. I have not yet done this but I believe the following is to adjust or center the armature bar. You insert a shop made threaded tool into the vacant threaded holes and push the armature bar in or out for adjustment. There is a little arm that sits above the armature bar to do a fine adjust in use. The arm is magnetic and is mounted to an eccentric screw arrangement that is accessible thru a hole in the side of the case. That is all for now.