The Beogram 4004 turntable from Texas plays its first record since its restoration.
The original (and only) owner of this beautiful Beogram 4004 turntable was an avid jazz lover so as homage to him I felt the first record played on the restored turntable should be a jazz record. I am fond of the trumpet and I like Freddie Hubbard so there you go. The red vinyl reissue of Red Clay also makes for a cool photo.
Now to backtrack to how I got here.
In the previous post I had completed the electric work checks and I ran some functional tests of the Beogram's analog control system. Everything was working perfectly. Although the control panel button board didn't exhibit any problems this is a good time to clean the switch contacts.
The fixed contact looks really good while the contact that engages with it shows some tarnish. That is to be expected. I removed all of the fixed contacts so I could clean all of the surfaces with a fiberglass brush and coat the surfaces with Deoxit.
The next step was to reassembly the control board and get all of the loose pieces reinstalled in the Beogram cabinet for some service manual checks.
The first service manual adjustment was the turntable platter height. It turned out to just be an adjustment check as this turntable was still at its perfect adjustment set by the Bang & Olufsen factory. Pretty amazing when you think about this being 2018 and this Beogram was made in 1978.
Note that this adjustment is made with the platter belt removed.
It is worth mentioning that in some of the pictures the lighting shows there are finger-wear marks on the control buttons of this Beogram. That means this was a well used turntable. Even more remarkable at how pristine this Beogram is. It didn't just sit around for show.
I put the platter belt back on and performed the platter speed adjustments next. This Beogram had its DC platter motor restored by Beolover. Combined with new electrical components (capacitors and speed trimmers) in the controller board, the speed trimmers need to be dialed in to set the platter speeds correctly for 33⅓ and 45 RPM.
On the next service manual adjustments I removed the platter belt again to check the tonearm lowering limit, tonearm length, tracking force calibration and the record tracking.
Everything was right on except the tracking force. I had to recalibrate the tracking force knob but it was no problem.
The linear tracking sensor of the Beogram is checked and adjusted by manually rotating the platter with a test record while the tonearm is engaged for play. The revolutions of the platter are counted as you observe the tangential tracking motor advance the arm assembly. I haven't found a good way to document that with still photos so here pictures of the the post adjustment check. In this case, like most of the other adjustments, the tangential tracking was already perfect.
This tracking check with the platter belt back on checks that the tracking control system keeps the stylus centered with the tonearm as stylus moves in the test record grooves.
Satisfied that the Beogram is adjusted properly for record play I finished reassembling the Beogram cabinet. That involved the last adjustments which are mainly cosmetic. The floating chassis has to be adjusted so the platter is centered in the deck opening and the platter surface is even with the Beogram deck.
That brings us up to date with the first record play test.
Before reinstalling the Beogram 4004 dust cover I will test play the Beogram connected to one of my stereo systems for a few days to make sure I didn't miss anything and exercise all of the new parts.
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