Kenwood KD-2055

[boreas]

Okay, what happens with the gold colored Return Arm as the tonearm moves toward the center? It should make contact with the Detecting Operation Arm when the stylus enters the run-out grooves. When the Detecting Operation arm has moved the Detection Arm into the path of the pin on the platter the Detection Arm will get a big shove which pushes it against the Center Arm. The center Arm releases the Reverse Rotation Preventer and the arm is raised and returned.

Wait! Did you say that the arm return works when you do it manually? Do you mean when you hit the Cut button? If that's the case then I think the mechanism is working correctly. It may be that the pin on the platter simply isn't hitting the Detection Arm so you'll have to adjust it's rest point. The Detection Adjust knob appears to be an eccentric. Rotating it will change the rest position of the arm, bringing it closer to or farther from the pin. Right now it appears to be set for the farthest distance from the pin or nearly so.

John

[Edit] I think you can ignore this second paragraph. I don't think the rest position is all that critical assuming that the Detecting Operation Arm and the Detection Arm aren't free to rotate independently on the shaft they're both attached to. What is critical is that the Return Arm pushes on the Detecting Operation Arm and moves the Detection Arm into the path of the pin.

I'm having a tough time visualizing what the Reset Arm actually does and what action of the Center Cam makes it do it.

 

[Doug G.]

John, I think he means that if he pulls the long white detection arm towards the front, the tonearm lifts which means the mechanism is basically working. Pulling the detection arm manually would be the same as operating the cut button if that is working OK, though.

But if the reset arm is missing, the parts will never get reset to their starting positions and the arm won't trip the macanism again on its own.

The detecting operation arm has to be loose so it can move fairly easily. It then moves the detection arm into the path of the pin sticking down from the platter (as John indicated) and this starts the lift and return action.

With the detection arm at its home position (against the adjustment screw), does it move when you manually push on the detecting operation arm?

EDIT: The reset arm is the backward question mark shaped one to which Preston referred.

Doug

 

[rang]

rang, after looking at your photos closer I see where the problem is...you are missing a part or parts that work in conjunction with the dectecting operation arm.

I've taken a quick pic for now and if we need more I'll do that tomorrow in the daylight.

See that curved, kinda like a backward question mark shaped white plastic piece to the left of the detecting operation arm? That is what your missing. HTH, Preston

Preston,

The reset arm is present but it is not setting up aginst the detecting operation arm like in the photo that you took.

 

[rang]

John, I think he means that if he pulls the long white detection arm towards the front, the tonearm lifts which means the mechanism is basically working. Pulling the detection arm manually would be the same as operating the cut button if that is working OK, though.

But if the reset arm is missing, the parts will never get reset to their starting positions and the arm won't trip the macanism again on its own.

The detecting operation arm has to be loose so it can move fairly easily. It then moves the detection arm into the path of the pin sticking down from the platter (as John indicated) and this starts the lift and return action.

With the detection arm at its home position (against the adjustment screw), does it move when you manually push on the detecting operation arm?

EDIT: The reset arm is the backward question mark shaped one to which Preston referred.

Doug

Doug,

that is correct the "cut" button works and when I move the detection arm manually. No the the detecion arm does not move when I push on the operation arm

 

[rang]

rang, after looking at your photos closer I see where the problem is...you are missing a part or parts that work in conjunction with the dectecting operation arm.

I've taken a quick pic for now and if we need more I'll do that tomorrow in the daylight.

See that curved, kinda like a backward question mark shaped white plastic piece to the left of the detecting operation arm? That is what your missing. HTH, Preston

Preston,

what does the rest arm do when you pull the player lever to play? does the reset arm pull away from the operation arm or does the reset arm still rest agianst the operation arm? Also is the operation arm tight on the detecion arm

Thanks

Eric

 

[Doug G.]

The detection arm should move when you push on the detecting operation arm. That is how the end-of-record trip works. This is probably based on friction at the base of the detection arm and if lube has gotten in there or something is loose, it will cause it to slip instead of moving with the detecting operation arm.

It looks to me like the reset arm should probably move out of the way after it has pushed the detecting operation arm back to its start position. You wouldn't want it to be right up against the detecting operation arm after that.

Doug

 

[pjsjr]

Eric, if I'm understanding your question, yes, the reset arm pulls away when the play lever is pulled.

As quoted by rang, "Also is the operation arm tight on the detecion arm"...

I'm not sure what you talking about here as there is a detecting operation arm and a detection arm refered to on page four of the service manual. These are two different parts separate of one another(if I'm reading and understanding the SM correctly).

The detecting operation arm does move and is moved by the return arm located under the tonearm...see page four for complete explaination.

As quoted by boreas "I'm having a tough time visualizing what the Reset Arm actually does and what action of the Center Cam makes it do it."

Me too, I've tried to look underneath and behind but I can not see what it is attached to. The diagram on page four shows that it is connected to the operation rod(that's connected to the play lever) and that in turn in connected to the return arm ass'y...without taking the TT apart I don't think we're going to have much luck locating the errant connection. Preston

 

[boreas]

Eric, if I'm understanding your question, yes, the reset arm pulls away when the play lever is pulled.

As quoted by rang, "Also is the operation arm tight on the detecion arm"...

I'm not sure what you talking about here as there is a detecting operation arm and a detection arm refered to on page four of the service manual. These are two different parts separate of one another(if I'm reading and understanding the SM correctly).

The detecting operation arm does move and is moved by the return arm located under the tonearm...see page four for complete explaination.

It appears to me that the Detection Arm ("DA") and the Detecting Operation Arm ("DOA") are attached to the same shaft. If I understand the function of these two parts, both are rigidly attached to the shaft so that movement in one arm translates to equal movement in the other. If that weren't the case, then the pin moving the "DA" wouldn't necessarily move the "DOA".

The "DOA" is what really does the work. It's what actually trips the mechanism. The "DA" is more or less an intermediate piece. The pin moves it and as a result the "DOA" moves and trips the mechanism.

If the Cut button works repeatedly I think that means the mechanism, including the Reset Arm, is working. It also means that the "DOA" is working since the Cut button acts on it.

If the tonearm doesn't return automatically at the end of play that probably means that the problem is that the "DA", the "DOA" or both are loose on the shaft. If they're loose then the pin will move the "DA" without producing the necessary motion in the "DOA". This could be true even if moving the "DA" by hand works. You're likely moving it farther than the pin does, taking up the slop between the two arms on the shaft and then tripping the mechanism.

John

 

[Doug G.]

What you are saying is true, John, except I think you have the two parts (DA,DOA)reversed. The DOA is the metal part acted upon by the tonearm return arm. The DA is the white plastic long arm acted upon by the pin that sticks down from the platter.

The two parts may or may not be rigidly attached to the same sahft. Many times, mechanisms like this use a friction surface between the two so, normally, one part will move with the other but if there is any obstruction, they can slip. Kind of like a clutch.

Doug

 

[rang]

It appears to me that the Detection Arm ("DA") and the Detecting Operation Arm ("DOA") are attached to the same shaft. If I understand the function of these two parts, both are rigidly attached to the shaft so that movement in one arm translates to equal movement in the other. If that weren't the case, then the pin moving the "DA" wouldn't necessarily move the "DOA".

The "DOA" is what really does the work. It's what actually trips the mechanism. The "DA" is more or less an intermediate piece. The pin moves it and as a result the "DOA" moves and trips the mechanism.

If the Cut button works repeatedly I think that means the mechanism, including the Reset Arm, is working. It also means that the "DOA" is working since the Cut button acts on it.

If the tonearm doesn't return automatically at the end of play that probably means that the problem is that the "DA", the "DOA" or both are loose on the shaft. If they're loose then the pin will move the "DA" without producing the necessary motion in the "DOA". This could be true even if moving the "DA" by hand works. You're likely moving it farther than the pin does, taking up the slop between the two arms on the shaft and then tripping the mechanism.

John

John,
that is correct the detection and operation arm are on the same shaft and I can move the operation arm and the detection arm does not move. (the operation arm is the metal arm that stickts up from the bottom of the detection arm through a hole in the mounting plate. The reset arm should push the detecting operation arm forward when either the cut or end of the record is done. There is a metal plate attached to the TA and seen in the photos that pushes against the detecting operation arm that then would push the detection arm out twards the pin on the bottom of the plater.

I would like to know if the detection operation arm the (metal arm at the is attached to the bottom of the shaft and sticks up through the bottom of the mounting plate) is tighly attached to the detection arm shaft? and if you move this by hand does the detection arm move with it?

on the TT that I have i can move the operation arm and then detection arm does not move and the reset arm has a hard time resetting the operation arm. It looks like all the hardware is there but it does not seem to work.

thanks for everyones input and help so far on this unit....

Eric

 

[boreas]

John,
that is correct the detection and operation arm are on the same shaft and I can move the operation arm and the detection arm does not move. (the operation arm is the metal arm that stickts up from the bottom of the detection arm through a hole in the mounting plate.

What about when you do the reverse? Does the DOA move when you move the DA toward the front of the table (in the same way the pin would)? That's the critical thing. (I think! We need someone to tell us how these parts move on their working table!)

John

 

[rang]

What about when you do the reverse? Does the DOA move when you move the DA toward the front of the table (in the same way the pin would)? That's the critical thing. (I think! We need someone to tell us how these parts move on their working table!)

John

everything works as should but the automatic return when the record is over.

 

[brucered]

i saw one of these locally and debated in picking it up, but the tonearm was so stiff to lower and raise and worried about having a $100 repair on my hands.

is the raise/lower issue an easy fix or is it possible that it is a major repair?

 

[jleon92f]

I think the most useful part is the solid heavy stone plinth.

I did not like the way the arm would return at super speed.

Sold mine.

Thanks,
John.

 

[Mailliw]

Regarding the broken auto-return mechanism:

I just bought a KD-2055 with this problem and was able to fix it. Doug G is spot on earlier in this thread - the detection arm is slipping on the detection arm shaft.

Intended operation: As the metal detecting operating arm (fixed to the metal detection arm shaft) rotates, the detection arm also rotates due to the friction between its plastic sleeve and the the detection arm shaft.

The service manual tells you to apply daphne oil to the detection arm, and IMO that is incorrect. Something more viscous is required to transfer the torque. I cleaned the shaft and the inside of the plastic sleeve with paper towel and applied a little vaseline (grease should work just the same) to the detection arm shaft. Works as intended now.

See the attached image.

Cheers!