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BRONZE MemberWhich active speakers are you considering? If not B&O you can pad the speaker output or use the headphone output directly.
What you are hearing when you physically touch the stylus is cantilever movement not the condition of the diamond. Have it checked under a microscope as it might be that the diamond portion might be missing.
My guess is that you are not really tracking at that weight. How did you measure 1.44g?
You simply need a Moving Magnet Phono Preamp even though your cartridge is a moving iron type. I can recommend the Schiit Mani as a great value. There are also ones from Parasound, Pro-Ject, and Rega to name other quality units.
3 November 2023 at 00:23 in reply to: Beomaster 5000 cuts out after 20seconds – what are the trimmers? #50078If you don’t have any test equipment such as a multimeter and oscilloscope, you should have it looked at by a B&O service tech.
3 November 2023 at 00:19 in reply to: Beomaster 1900 – No sound in left channel on phono/tape input #50036From the diodes D200, 201, & 202 all three sources share the same circuit. So I would start by checking whether you have a signal on the anodes of D200 (Phono) and D201 (Tape). If not then I would trace back into their respective preamp circuits.
This is a common problem. You need to disassemble and clean the pivot point that the spring /arm is attached to as well as the up/down pivot that the solenoid plunger moves. Both of these get gummed up through non-use.
The signal path is described later in the service manual where you have gotten the schematic.
Yes, the platter is the metal disk that the record supports and when shipped from the factory it is removed and in its own styrofoam piece. The stylus will not scratch it but if its loose it can destroy the cantilever that holds the stylus as well as the tonearm.
To reattach the cord, download the service manual from either the Members area here or Beomanuals.com. You will see the pictures.
I would not accept a shipment where the platter and cartridge were not removed. Padding can help it survive without the transport screws engaged but an in place platter will likely cause damage. You are correct that the cord is necessary for arm movement as it goes around two pallets that are driven from the arm motor.
Have you checked the fuse as the load surge may have blown it?
The base of TR45 should be adjusted to 27.2 which should give you 26.6 at the collector of TR48. If the base of TR44 is 29.2V and you still are seeing a drop to 22V then the speaker output voltage before the output cap can’t be 28v. Note that the positive side has an 100 ohm resister to isolate it where the negative doesn’t. You need to further investigate after TR47 for the current draw.
The 250-ohm trimmer and TR45 governs how much no load bias is applied to each base. It is mounted on the heat sink to sense temperature and also adjust the bias. It’s possible that transister is bad or the adjustment is too high. The circuit calls for a BC311 and since the bias is not separately adjustable for its BC310 mate its possible that your BC161 is a poor match. Sorry, but its been too many years since I worked on one of these.
Glad you got it sorted out as I was out of suggestions. First try the bias adjustment.
The diode is blocking current flow from TR48 collector to base of TR47 as it conducts in the other direction due to the higher voltage that is supposed to be on the base. Therefore, it cannot be bypassed with a jumper.
You say there is 0 volts on the anode, is it the same at the collector leg of TR46 and the base leg of TR47? If you power down, what is the ohms reading to ground from the anode for each channel?
It’s possible you have a broken trace at the anode of the diode. Try a jumper from it to the base of TR47 and the collector of TR46. Don’t know what else to suggest based on what you are reporting.
You misunderstood my suggestion. If the voltages are not as specified in the schematic the transistor will not turn on even if it is good. What are the actual base and emitter voltages?
It sounds like TR46 is not being turned on. Are the voltages on its base and emitter as per the diagram?
I just did some more troubleshooting, The tracking force seems to be right, 1,19g (measured with a jewelers scale). It randomly skips/repeats the groove, maybe every 20-30 seconds. I can’t see any obvious reason why and the tonearm seems parallel to the sensor arm the whole time, even when it skips.
I would remove the platter and press play without the record. Once the arm drops, I would tap it just enough for it to start progressing in. This way you can observe where or when it may be hanging up.
As to your standby problem, I would try running the TT without connecting to the Beomaster and seeing if it still stops.
Since this occurred when using the turntable and the FM still works I would check the solenoid circuits 21RL1 and RL2 sad their switching transistors 19TR4 and TR5. These would also explain the Pause not working. There are adjustments for arm position and balance in the service manual to solve your alignment and tracking issue.
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