Marantz 6300 Project

[musicSteve]

You're spot on with your analysis. The "motor strength" on the 6300 does indeed have weak torque - especially on initial start-up and after stylus drop. I doubt that you'll notice any measurable improvements after putting in new electrolytics in the motor. Mine still drifts a little, and I have to tweak the pots to get it to settle in at first, but once I run it for awhile it stays steady. I assume the initial speed drift is due to the cold temperature on the drive coil transistors and oscillator, but as it warms up it settles down.

Unfortunately, the 6300 motor did not have a quartz lock design feature like the 1200. The quartz crystal, if i understand the theory correctly, offers more stability regardless of temperature. Still, even with all of it's flaws, I still enjoy mine. Good Luck!

Thanks for the Restore information. Very helpful ,Will have to restore mine.
I changed my 33 rpm pot which never worked even when New (drifted)
I took it apart and added 3 wires to I think was a 10 turn pot or 20 decades ago And I ran the wires under the bottom cover outside and to a External Pot been that way for decades and is right on for speed (when I restore it I will try to find a 10-turn or 20 that will fit. The one I'm Using is to big.

 

[tonefoto]

Thanks for the Restore information. Very helpful ,Will have to restore mine.
I changed my 33 rpm pot which never worked even when New (drifted)
I took it apart and added 3 wires to I think was a 10 turn pot or 20 decades ago And I ran the wires under the bottom cover outside and to a External Pot been that way for decades and is right on for speed (when I restore it I will try to find a 10-turn or 20 that will fit. The one I'm Using is to big.

This thread is fantastic, information very helpful. Thank you for taking time to post this Echoplex. My issue is perhaps unusual. The auto lift at record end is working properly and adjusts fine. The auto motor shutoff is not working however. Would that photo thyristor be the cause?

 

[bad_robot]

In auto mode, if the Photodarlington (ph101) is operating the auto lift relay (s007) at record end OK, then it should also turn off s006 and also the motor off (s005) and disconnect the tone arm micro switches (s009 s010)
The cue up operates a relay (h101) and sets s003 s005 s006 s009 and s010 in the latched position (off). So if you do a cue up and the tone arm lifts but the platter still turns, then the problem, in my opinion, is most likely with the motor shut off switch (s005) or its wiring. I would check s005 first.

 

[tonefoto]

In auto mode, if the Photodarlington (ph101) is operating the auto lift relay (s007) at record end OK, then it should also turn off s006 and also the motor off (s005) and disconnect the tone arm micro switches (s009 s010)
The cue up operates a relay (h101) and sets s003 s005 s006 s009 and s010 in the latched position (off). So if you do a cue up and the tone arm lifts but the platter still turns, then the problem, in my opinion, is most likely with the motor shut off switch (s005) or its wiring. I would check s005 first.

First, thanks for posting your info. So if the lift operates at record end but the motor spins then its likely S005. Does this mean I can eliminate the PH101 circuit at the culprit? Does the cue up button activation in AUTO position always result in motor off in cueing or record end lift?

 

[bad_robot]

if the lift operates at record end but the motor spins then its likely S005. Does this mean I can eliminate the PH101 circuit at the culprit?
YES - you should hear the relay operate as a clunk sound after tt on and auto is down (manual is up) and cue down pressed
Does the cue up button activation in AUTO position always result in motor off in cueing or record end lift?
In auto mode, cue down will always turn the motor on and lower the arm, cue up will always raise the arm and stop the motor

 

[tonefoto]

if the lift operates at record end but the motor spins then its likely S005. Does this mean I can eliminate the PH101 circuit at the culprit?
YES - you should hear the relay operate as a clunk sound after tt on and auto is down (manual is up) and cue down pressed
Does the cue up button activation in AUTO position always result in motor off in cueing or record end lift?
In auto mode, cue down will always turn the motor on and lower the arm, cue up will always raise the arm and stop the motor

I exercised S005's microswitch a bit, sprayed a little faderlube on the contact and got it to work, shutting off power as it should. Then I discovered I had to lose the left channel signal. Got that to work by just looking at it sideways, but it cuts out intermittently. Holy crap. These are fun! I guess its the muting on the left channel? I replaced the rca connectors previously, not sure if it could be the cause, sort of doubt it.

 

[bad_robot]

Also check s009and s010 which disconnect the channels - if one switch (like s005) is sus then these could be as well
The tt is over 55 years and anything can go wrong to create a lot of fun times

 

[NMA]

Hi there (many years later). Up/Down/Auto/Manual/Start/Stop = Loud `POP` :-( Any idea if replacing all the micro switches, re-capping the power board and motor (which I will do anyway) will put an end to this? Or is there something else I should be looking at? Thanks!

 

[Oerets]