A Kind Of Blue And A Bit Mike New - Changing My Top Plate An

by **hamish_gill** » 19 Apr 2010 10:36

ha, very nice!!

by **Blue Angel** » 19 Apr 2010 14:33

Thanks

ba

by **mikenew** » 22 Apr 2010 13:25

Hamish_gill

I notice that you have the top plastic cover installed over the coil assembly. My installation notes say to remove this, as this cover interferes with the locating posts on the bearing which are deliberately longer to enhance the locating of the bearing into the coil assembly. Your speed problem might be because you have not properly located the bearing vertically, which will mis-align the 8 pole switching rotor with respect to the sense coils.

However what you explain is also indicative of the 8 pole centre piece being out of position with the ferite magnet. The two componenets have an exact radial relationship. It maybe that your ferite magnet has moved in it's pressed metal cage. They do come loose I have discovered.

During the course of designing the new platter; I have discovered that it is possible to make the platter rotate in reverse, and indeed when you press the stop button the platter speeds up and does not stop!!
This is caused by the incorrect radial location of the rotor with respect to the magnet, (which has 16 radial poles) and acts as a rotary switch controlling the 12 motor drive coils.

by **hamish_gill** » 22 Apr 2010 15:34

How can I fix it mike?
I have now removed the black plastic bit...
It does sound like you have experienced my exact problem so any help with this would be greatly apriciated!

by **mikenew** » 23 Apr 2010 00:19

Hamish_Gill,
I believe that Dave is also across your problem from the AOS site. so I do not want to cut across his good work for you. It could well be that you have a circuit board problem.

Have you replaced the three plugs correctly into their sockets. Check that the the rotor in the centre of the platter is not loose. also check that the magnet does not rotate in it's metal cage.

I have discovered that on some earlier models the glue does not adhere tightly to the ferite magnet material.

Maybe the motor cannot handle all Blue!!!

by **mikenew** » 23 Apr 2010 00:26

Hamish,
I have just studied all your images and I believe I may have the solution.
You have connected the earth wire to the top right hand corner of the PCB. On my PCBs this corner pad is not connected to the PCB earth path.
Try clamping the wire to the bootom left hand corner, as this has a positive connection to the negative (earth) of the PCB.

by **hamish_gill** » 23 Apr 2010 14:06

mikenew wrote:Hamish,
I have just studied all your images and I believe I may have the solution.
You have connected the earth wire to the top right hand corner of the PCB. On my PCBs this corner pad is not connected to the PCB earth path.
Try clamping the wire to the bootom left hand corner, as this has a positive connection to the negative (earth) of the PCB.

shouldn't make any difference mike, but I will try it...
Just had a chat with dave about it, I have to say I think it is probably the motor not being in line with the magnet as you said...
Or maybe I should have gone with red

I'm raising some money for a tt to butcher for bits then I'm gonna send the current pcb to dave for him to have a look at...at least that the current plan...
The only issue at the mo is I have to manually spin start it and manaually stop it once it starts speeding out of control... Once it's going the speed, acording to te strobe is spot on!

by **hamish_gill** » 23 Apr 2010 18:52

You mean to tell me my 1210 isn't good enough dave

I will no doubt be taking you up on your offer dave, which ever way I aproach the fix...
Still it's kinda working at the mo, at least well enough for me to listen to music ... So I'm happy for now!
Will be good to ge it sorted eventually though!

by **mikenew** » 23 Apr 2010 23:50

Hamish,
To totally illiminate the platter (magnet/rotor) can you borrow another platter to test the system with.

Mike

by **hamish_gill** » 24 Apr 2010 12:21

mike, tried it, no good

i think dave is right about the ic's
stupidly i have been messing with it trying to get it to work right without listening to it - i didnt want to damage my new oc9, got it working pretty much perfectly this morning put a record on and despite the strobe looking like its steady it sound absolutely terrible ... maybe the uv strobe shows less??..not sure , what i do know is its speed is not steady at all, any constant notes sound like someones playing funny buggers with a wahwah peddle... not good at all... so... im going to buy a working deck and swap the pcb over, il then send the dodgy pcb to you dave for your inspection and tinkering

by **hamish_gill** » 25 Apr 2010 10:22

... That's cool dave, that's why I want to get a deck to butcher ... After dragging my feet over that insurance claim and not having my tt for 4 months any hint of patience I did have has long since evaporated.
Obviously that's not your problem, or reposibility, but if I get a new secon hand deck and get you to get this pcb sorted I get mine quicker and my mate gets a good properly working one in a month or so ... He wont mind waiting

by **hamish_gill** » 25 Apr 2010 10:27

... ... I don't supose you know how to tell, maybe by serial number, certainly without taking the deck apart, if a 1200 series deck has a pcb with White wiring connectors or black ones... They arnt compatible without rewiering things and at this stage I don't want to be forced to do that as it gives me far to much room for mistake...

by **futurproof** » 25 Apr 2010 14:01

Search ebay for seller - frieben102

by **hamish_gill** » 25 Apr 2010 19:35

futurproof wrote:Search ebay for seller - frieben102

cheers, very usefull for futur ref but i just bought this

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 526wt_1165