Tonearm Adjustments
Jumping right into things, tonearm adjustments are as follows:
* Set-down position:
According to the IOM, proper position of the set-down position of the tonearm (the stylus, or "needle") is 3/32" from the outside edge of a 7" (45 RPM) record. This is accomplished by adjusting a screw located at the rear of the tonearm (circled in orange below):
I found the outer diameters of the 45's I had on-hand varied so much that this measurement was almost hard to nail down, so I made this adjustment based on a "best average" across all of the 45's I had installed in the unit.
* Cut-off position:
According to the IOM, the record cut-off position is 2-1/32" inches from the center of the hole measuring outward. I found this somewhat cumbersome to measure, so once again I simply used a "real world" methodology, and made this adjustment using the old 45's I had installed in the mechanism to ensure that the tonearm switch closed just before the stylus reached the innermost cut-out groove.
The Tonearm Switch is seen here:
Notice there is a small lever (yellow arrow, below) which pivots with the tonearm (it is part of the rotational assembly), and this lever pushes against a "bumper" located on the rearmost Tonearm Switch lever (circled in orange). When the tonearm reaches end-of-play, this lever pushes against the "bumper", which closes the Tonearm Switch.
Although it seems rather crude, adjustment of the cut-off position is accomplished by bending this lever (I used a small needle-nosed Vice Grips, as seen in the video).
* Trip Dog lever:
After making the cut-off position adjustment, one must also adjust the Trip Dog. Essentially the Trip Dog is almost like a "check valve" which, according the IOM "....is a safety device to prevent re-playing the same record by jarring the tone arm back against the record". (Much like how people use a little "English" when playing pinball, apparently people attempted the same thing with jukeboxes back in the day to get their records to play over again!)
Here's a shot of the Trip Dog (circled in orange):
Adjustment is made via these two screws (circled in green):
The adjustment is a little finicky, but what you want to accomplish is to see the Trip Dog "release" just before the Tonearm Switch makes/closes. In other words, the Trip Dog needs to release before the tonearm reaches the lead-out groove (cut-out position), but after the record has completed playing. (See time stamp 4:07 in my video, linked below).
* Tonearm Height:
The height of the tonearm needs be adjusted so that the stylus just touches the flocking on the turntable. I can't make this adjustment yet, as I'm still waiting on my flocking supplies (I had the turntable re-chromed), but I think I got it pretty close. I don't have a picture of this, but I mention it in the video.
Tonearm height is adjusted via this stud here (red arrow):
* Tonearm "Liftover Height":
When an even-numbered selection is entered, the Gripper Arm will rotate to the right, and will come to "rest" in-between the Tonearm and the turntable. Seen in another way, in order for the stylus to play the record, the Tonearm will need to reach over the Gripper Arm, and the "liftover height" (my term) needs to be adjusted so that there is between 3/16" to 1/4" of clearance between the bottom of the stylus and the top of Gripper Arm as the Tonearm moves over the Gripper Arm.
Here's an old picture I dug-up that may help explain what I'm talking about:
Tonearm "Liftover Height" is adjusted via this stud here (blue arrow):
* Vertical Tracking Force:
Vertical Tracking Force is adjusted by inserting a 5/64" Allen wrench into the hole located at the rear of the Tonearm:
Which will engage the setscrew seen here (blue circle):
This setscrew applies pressure to the "Tonearm Spring" (the copper-looking part), and adjustment is simply down/in/CW for more VTF, and up/out/CCW for less VTF.
Link to video: https://youtu.be/czlAFelgHHU
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