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BRONZE Member1D16 is a Zener diode that is supposed to set the base voltage of 1TR5 which turns on the lamp in the detector arm. If it shorts it not only will not keep the lamp off but will pull down the 22V rail that will impact other circuits such as the solenoid driver. Glad you got it working again.
First, if you are only getting 18v then there is still a power supply problem. I would work backwards to see where the voltage drop is occurring. You could still have a bad cap or transistor. As to 1R36, you may have a bad Zener diode, 1D17.
You may have an issue with the 22v DC supply that feeds both circuits. Lowering the arm with the cuing control does not need the lamp working. Check that you have 22.8V on the high side of 1R42 and 12v on the collector of 1TR11 when the table is on and the arm is stopped before the record. If this table has not had a capacitor replacement, it is long overdue and where I would start. You can get a service kit for your model here.
For your system, going to the SMMC2 would be well along the diminishing curve with the rest of your system. The SMMC3 is the sweet spot.
I cannot recommend turntable needles.com as I have no experience with them. Any of the MMC cartridges will work with your table; however, if it was me, I’d go with the SMMC3 from Soundsmith. B&O used them for the release of the Beogram 4000C using an SMMC20CL. This gets you the nude hyper-elliptical diamond where the 4 is a bonded diamond.
I really doubt it and actually am quite appalled. Here they are offering a limited edition $30K system and only supplying an MMC4 cartridge! As an alternative to Soundsmith (which I have used) there is turntableneedles.com that advertises new MMC cartridges.
The 4002 employs both static (weight) and dynamic (spring) tracking force adjustments. With the dial at 0 you need to adjust the rear counterweight using its screw so the arm floats with 0 tracking force. Then the knob should apply the specified force by adjusting it to your cartridge’s requirement.
29 May 2025 at 02:45 in reply to: Recommended Load Capacitance for MMC-20EN, MMC-20E, SP-12, SP-10? #65892B&O cartridges are not very sensitive to capacitive loading. Simply adjust your setting by ear but remember that the cables are already going to contribute to the value.
Those controls are actually photoresistive and depend on a lamp on the board to operate. It likely burned out, or there is a bad solder connection.
ALF, those jumpers most definitely need to be removed as they are shorting the inputs to the outputs which will cause oscillation. Glad to see you got it working, Enjoy!
It’s not really a mystery as a short will not take out your cartridge coils since they are not conducting current. If you are reading 6V DC on each of the + and – inputs then the passive components are likely fine, and your issue is the ICs. You should use hot air and flux to replace the ICs. There are plenty of YT videos showing how.
Actually, pins 2 and 6 are the feedback loop inputs and not the signal inputs. Pins 3 and 5 are the inputs and 1 and 7 the outputs. I don’t know what you mean by “checking the inputs” because putting a probe on an input of a high-gain stage will produce an audible side effect. Given how inexpensive these opamps are, unless you find a burned part, it is easier simply to replace them as long as all the voltages check out.
There are 2 voltages going to the board – 22v and 12v. First, I would unplug the board and check that the power supply is outputting the correct voltages. Then after removing the power cord, I would reinsert the RIAA card and check the voltages on it per the service manual. Make sure you check for 12v on each IC. Since each IC is amplifying both channels, a bad one can impact both. If you have an oscilloscope, you can check the nature of the noise and the point in the curcuit that it is originating from.
Assuming it does not have a phono preamp board, it depends on what input you are connecting to. If you are going to a DIN Phone input, you need a 5-pin DIN cable. If you are connecting to an RCA phono L/R jacks, you need a shielded pair plus a separate chassis ground wire.
In the US there were no finish choices. The base was a dark gray matte plastic.
If you do not have continuity between the cartridge body clip, board ground, chassis ground and external ground wire you will get hum.
Across the many 40xx turntables I have serviced, I have never replaced the pulley of a working motor. You’ll be fine with the proper belt and shaft pulley.
There is no need to replace the motor pulley if it is not cracked or deformed.
It looks like your tonearm’s azimith adjustment is way off with the left side too low as viewed from the front. There is a separate adjustment in the manual for that.
The motor circuit requires the 15v supply to operate. The TURN button is used to rotate the record for cleaning, not the 33 speed button as was the case on the older models. The 45 button never turned the platter.
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