Mark-sf

Forum Replies Created

Viewing 20 posts - 61 through 80 (of 294 total)
  • Author
    Posts
  • Mark-sf
    BRONZE Member

      It sounds like the End of Travel switch is not engaging early enough. This can be either the adjustment of the plastic optical right angle piece that  engages it or the parallelism of it to the threaded rod that the arm moves on. You should also clean its contacts.

      Mark-sf
      BRONZE Member

        I can’t tell from your picture but the correct orientation is marked on the board.

        in reply to: Beogram 3000 5901, motorcontrol schematic #22039
        Mark-sf
        BRONZE Member

          You do not apply oil to the bearing. It needs to be infused in a vacuum. My experience is that they are still the source of your noise.

          in reply to: Beogram 3000 5901, motorcontrol schematic #22006
          Mark-sf
          BRONZE Member

            The motor was considered a single part so B&O did not publish the control-board schematic. What is the nature of the problem you are experiencing. Most of the time its the bearing drying out not an electronic issue.

            in reply to: MMC20 Type A cartridge #21851
            Mark-sf
            BRONZE Member

              That may be an old Soundsmith MMC cartridge as they used to make them with gold-tone cases. They are a B&O licensee.

              in reply to: Beogram 4002 Type 5513 45 RPM Not Functioning #21825
              Mark-sf
              BRONZE Member

                John, great to hear you were successful and the forum proved valuable. Enjoy!

                in reply to: Beogram 4002 Type 5513 45 RPM Not Functioning #21763
                Mark-sf
                BRONZE Member

                  Glad to hear it is now working. Yes, if the arm is at an angle when tracking, that means the shutter is not properly adjusted. Please follow the procedure in the service manual and everything should be fine. If you find you are at the adjustment stop, then the shutter clamp around the base of the arm has been moved and can be mechanically adjusted to give you a new center point.

                  in reply to: CX50 foam or rubber #21264
                  Mark-sf
                  BRONZE Member

                    Specifically changing from foam to rubber will alter the low frequency resonance changing the bass response.

                    in reply to: 1800 turntable belt ? #21263
                    Mark-sf
                    BRONZE Member

                      You lift the platter off and place it around the sub-platter and motor pulley.

                      in reply to: Beocenter 7700 power supply problem #21103
                      Mark-sf
                      BRONZE Member

                        Troubleshooting FM sections is difficult without the right test equipment. If you’re getting a hum I would first focus on whether all of the power supply voltages are correct before changing any VRs. It really helps to have a signal tracer or at least a scope so you can check the RF section.

                        in reply to: Beocenter 7700 power supply problem #21068
                        Mark-sf
                        BRONZE Member

                          Glad you are making progress. That antenna is for AM reception though it will work. B&O supplied dipole wired one or one with two hinged rods for FM like this

                          in reply to: Beocenter 7700 power supply problem #21038
                          Mark-sf
                          BRONZE Member

                            Either FM jack is fine as it depends on the type of antenna. If using a dipole wire type you should use the 300 ohm. 75 ohm is for a coax-based external antenna.  Regarding your cassette, have you replaced the belts and check the idlers/pulleys for freedom of movement? As to the display, unless you have bad solder joints if those segments never light up then it is likely the LEDs.

                            in reply to: Beogram 4002 Type 5513 45 RPM Not Functioning #20914
                            Mark-sf
                            BRONZE Member

                              Setting the tracking force is a 2-step process adjusting the counterweight for balance and the knob controls the force via a spring. When adjusting the counterweight it can get skewed by binding on one of its support slots. The same bracket has a V-support that the lift solenoid engages governing its cued alignment. Either of these can skew the arm.

                              • This reply was modified 10 months, 3 weeks ago by Mark-sf.
                              in reply to: Signal generator help #20746
                              Mark-sf
                              BRONZE Member

                                Such a device will work for this particular setting assuming your multimeter supports RMS readings to 1K. An alternative would be to use an app on your phone or tablet such as AudioTools that actually provides a cleaner output and offers more functionality.

                                in reply to: Signal generator help #20681
                                Mark-sf
                                BRONZE Member

                                  As a former B&O service tech, I have always used RMS as the AC voltage measurement unless it was annotated as p-p. This is standard across the industry because it is equivalent to a DC measurement for example when computing current draw.

                                  • This reply was modified 11 months ago by Mark-sf.
                                  in reply to: Signal generator help #20571
                                  Mark-sf
                                  BRONZE Member

                                    It generally refers to RMS for such adjustments and you can use a multimeter wit RMS support to measure.

                                    in reply to: Beogram 4002 Type 5513 45 RPM Not Functioning #20479
                                    Mark-sf
                                    BRONZE Member

                                      Assuming the LED is getting power, I would check that the collector of 1TR17 transitions from 0 to 20v when a black stripe goes by. BTW, the service manual has a troubleshooting flowchart for this specific issue.

                                      in reply to: Beogram 4002 Type 5513 45 RPM Not Functioning #20428
                                      Mark-sf
                                      BRONZE Member

                                        There is a clear right-angled plastic piece that has black lines on it that moves with the tonearm There is a lamp in a black plastic housing that illuminates a photodarlington transistor. I would check that that lamp is working. If it is, the the transistor may be bad. The detection of those black lines are necessary to find the edge of the record, switch to 45 and return after playing.

                                        in reply to: BeoMaster 7000 – what is correct std by temperature? #20372
                                        Mark-sf
                                        BRONZE Member

                                          The 7000 has active cooling using a fan. Is that running? Are you measuring this at idle? I believe the fan kicks on at 50 degs.

                                          in reply to: Beogram 4002 Type 5513 45 RPM Not Functioning #20363
                                          Mark-sf
                                          BRONZE Member

                                            Only the 33 button will cause the platter to spin for cleaning purposes. Once you have the arm moved over and paused, then pressing the 45 button should change the speed and illuminate.  Can you move the arm over using the Play button and push the Cue buttin to cause it to lower and begin playing. If that doesn’t work, there may be an issue with the solenoid circuit or its mechanicals. The area should go up and down with the Cue button at any point except rest.

                                          Viewing 20 posts - 61 through 80 (of 294 total)