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My turntable is causing a hum through the speakers, but only when the cue lever is in the up position. Also, I can hear a static sound through the speakers when I raise and lower the tone arm with the cue lever.There is no hum at all when playing a record or when the arm is at rest in the lowered position. And no static sound except when pushing the cue lever up or down.
The turntable is a vintage Philips AF877 and the amp is a Rogue Audio Cronus Magnum II (tube integrated with built in ss phono stage). The cart is a Shure 97Mxe.
Any thoughts on what the cause of the hum and/or the static sound might be and how to address it?
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
Edits: 02/13/17Follow Ups:
Looking at the Owner's manual on Vinylengine, it seems that one must cue the arm manually, to start, but that at the end of the disc it cues itself up automatically. Is that right?
If this is the case, then there's a motorized cueing actuator in there somewhere. It seems the cueing might be all done by the actuator, the lever just being in effect a switch that turns on the actuator. Look for bad grounds in the switches and actuator.
Does the the audio output mute when the cueing goes to the up position? I saw a muting switch on the schematics. Is it working? If so, there's another spot to look for grounding problem.
Ground connections wer out, get corroded, fall off, etc. One thing that has worked for me has been to connect a separate length of wire at the connection of the phono ground wire to the preamp, strip the other end a tiny bit, and go around touching the various metal bits of the turntable until the hum/noise is cut. You can then dig in and find the bad ground or defective component.
The Service manual is on Vinylengine, I looked briefly but, man, it is totally inscrutable to my brain.
Yes, you are correct about the cuing arm. It's clearly a switch rather than a mechanical connection. And it does return and shut off automatically (and without any issues there). I don't know whether there is a muting circuit in the up position.And all of what you say makes sense to me on a basic level.
Unfortunately, I printed out the Service Manual awhile back from Vinyl Engine (before I noticed this problem). And, well . . . suffice it to say that you are able to follow it far better than I am!
I wonder how much it would cost to have it fixed. First I'd have to find someone who is even interested and qualified I guess. Since it's not interfering with playback I'll probably just let it go for now.
Thanks for your input. Really appreciate it!
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
Edits: 02/14/17
There is probably a motor that raises and lowers the arm. There must be limit switches that stop the motor at the end points. Maybe in the up position the motor is not turning off.
Thanks. I bet that's it, because as you say it's not a direct mechanical connection between the cue arm and the separate lift mechanism at the back of the arm.
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
Maybe bad tonearm wiring.
You'd think so, but actually there is no hum when I manually raise or lower the arm or otherwise move the arm around, or when I play records. The only time it hums is when I raise the cue lever. There is a static sound through the speakers when I start pushing the cue lever back and the hum starts once I have pushed it back beyond a certain point and continues if I leave it in the up position. Otherwise the table is dead silent.This TT is all electronic and semi-automatic, so it might be hard to diagnose. Fortunately it doesn't interfere with playback at all or with any other operational function.
___
"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
Edits: 02/13/17
oxidation in the cueing system....? try some DOxit or similar in the devise. I wouldn't get any in the arm bearings though....
Sounds good, and I have some Deoxit, so that should be easy enough to try out.
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"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."
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