Well I 'm puzzled because my MK III uses a 24 VDC supply. There is no internal regulator on the driver board.
For the MKIII I use a 50 watt torroid, soft recovery diodes, CLC filter, a LM 329 referenced 317 pre-regulator then' LM 329 referenced LT 1085 then 50,000 uf.
It's easy to build a beefier version of the 'Turbo' supply for about $100, rather than the $1,000 Oracle charges.
For the MKIII I use a 50 watt torroid, soft recovery diodes, CLC filter, a LM 329 referenced 317 pre-regulator then' LM 329 referenced LT 1085 then 50,000 uf.
It's easy to build a beefier version of the 'Turbo' supply for about $100, rather than the $1,000 Oracle charges.
Well. Here I am again with the same problem. Things worked well for a few days but after not using the turntable for about a week it would hardly spin up and then ran slow. and inconsistently.
As per your advise I removed the oil in the well and replaced with synthetic 5w40 motor oil and ran the turntable for a number of hours, then it seemed to work fine.
Next day it ran slow when first turned on and once up to speed, after about 15 min., was ok. It then sped up momentarily then settled down.
Now I can not get it to maintain proper speed.
I have not lubricated the motor shaft again as I wasn't sure if the SAE 20 electric motor oil should be used. Can any one advise which type is correct?
All suggestion as to where to begin trouble shooting are welcome.
The belt is just over a year old. It's a 19.7. I have not tried putting a twist in it.
Checked the output on the wall wart. It states "Input VAC 120"; "Freq. 50/60 Hz"; "Output 12 VAC/1A"
It also says "To be used with Series III only."
My output voltage ranges from 13.29 to 13.39. It mainly stays at 13.30-13.33 v then may pop to 13.34-13.36 v for a short while, with the occasional momentary fluctuation to either 13.29 v or 13.38-13.39 v. Would this be considered normal and within tolerance?
It also says "To be used with Series III only."
My output voltage ranges from 13.29 to 13.39. It mainly stays at 13.30-13.33 v then may pop to 13.34-13.36 v for a short while, with the occasional momentary fluctuation to either 13.29 v or 13.38-13.39 v. Would this be considered normal and within tolerance?
Make sure your belt is clean and not handled with your bare hands. Consider what happens with a small dia. Motor pulling a big platter and it sees a slippery road ahead..
You get the idea. Just use some rubbing alcohol and clean the belt and platter,s belt path.
Then you can eliminate another area.
Regards
David
You get the idea. Just use some rubbing alcohol and clean the belt and platter,s belt path.
Then you can eliminate another area.
Regards
David
To clean rubber belt, try this:
(Asalco - Products - Electronic Maintenance Products - Specialty Products)
Very efficiency.
Cyr-Marc
(Asalco - Products - Electronic Maintenance Products - Specialty Products)
Very efficiency.
Cyr-Marc
I used to distribute Asalco products. Still have one of their ball caps. I think I have a small bottle of rubber renew buried in my cellar. Will pull it out & give a try.
Dug out my rubber renue and cleaned my belt. The belt stretched so much it's too long to stay on the platter. Ruined it. Off to get another one.
Yes, very odd. It actually states on the bottle's label that it is to be used on belts. Perhaps the belt was shot anyway, even though I bought it only 15 months ago.
Update us on your Oracle projects
Just checking in to see how everyone is doing with their Oracle projects. Did you get all of your troubles worked out and if so, could you please update us?
I am about to get out my Delphi MKIII after a few years in storage. I have been using my SP-10MKII for the last few years but I am starting to get into turntable and tonearm/cartridge tuning and want to give the Oracle another spin. I may do some upgrades to the PS and give her a full lube and oil change. I have a mint Fidelity Research FR-64fx and half a dozen different cartridges to try on it.
It currently has a Rega RB300 on it.
Look forward to hearing your results.
Cheers
Paul
Just checking in to see how everyone is doing with their Oracle projects. Did you get all of your troubles worked out and if so, could you please update us?
I am about to get out my Delphi MKIII after a few years in storage. I have been using my SP-10MKII for the last few years but I am starting to get into turntable and tonearm/cartridge tuning and want to give the Oracle another spin. I may do some upgrades to the PS and give her a full lube and oil change. I have a mint Fidelity Research FR-64fx and half a dozen different cartridges to try on it.
It currently has a Rega RB300 on it.Look forward to hearing your results.
Cheers
Paul
my Alex MkII...
...has been sitting idle with the 309 and Sig8 mounted. I am using my old re-plinthed Sugden BD-1, another grado Sig8 and my 219 (DIY) tonearm. The old Sugden is in the same league as the Alex MkII, although the Alex is still a very fine table. I doubt I shall ever part with it.
As I stated in my tonearm thread, be careful regarding the arm/cartridge resonance. Look here for my last post and a link to a calcukator to help out.
The Delphi and Premier tts were my dream, but I settled for an Alex, which is as good as a Delphi in my experience, although I do feel that the Alex's plinth colours the sound. A re-plinth and the removal of all electrical circuits is on my list of mods that I would like to do...
...but I've been busy with the 219 thread, and also a tt thread as well which is centred on far less sophisticated (as in absolutely cheap!) turntables that can have their performance increased disproportionately to the small amount of $$$ that is required.(Sorry for this little bit of pandering....)
One issue that I suspect with many of these turntables is the age of them. Capacitors can fail over time as well as resistors, affecting the control circuits. I've checked the speed of my Alex using a digital tachometer (while playing a record) and it is 33.4 RPM +/- 0.05 RPM. I suppose I better get a test record to check things out further.
...has been sitting idle with the 309 and Sig8 mounted. I am using my old re-plinthed Sugden BD-1, another grado Sig8 and my 219 (DIY) tonearm. The old Sugden is in the same league as the Alex MkII, although the Alex is still a very fine table. I doubt I shall ever part with it.
As I stated in my tonearm thread, be careful regarding the arm/cartridge resonance. Look here for my last post and a link to a calcukator to help out.
The Delphi and Premier tts were my dream, but I settled for an Alex, which is as good as a Delphi in my experience, although I do feel that the Alex's plinth colours the sound. A re-plinth and the removal of all electrical circuits is on my list of mods that I would like to do...
...but I've been busy with the 219 thread, and also a tt thread as well which is centred on far less sophisticated (as in absolutely cheap!) turntables that can have their performance increased disproportionately to the small amount of $$$ that is required.(Sorry for this little bit of pandering....
)One issue that I suspect with many of these turntables is the age of them. Capacitors can fail over time as well as resistors, affecting the control circuits. I've checked the speed of my Alex using a digital tachometer (while playing a record) and it is 33.4 RPM +/- 0.05 RPM. I suppose I better get a test record to check things out further.
Solved my problem in consultation with Jacques Riendeau at Oracle. I can not speak highly enough of him. After many emails and phone calls diagnosing things I sent the bearing and platter back to the factory. Things were out of whack. He re-calibrated and that along with an"Oracle Brand" belt solved the problem. I also switched to a 0W-50 synthetic motor oil as I was told the 20w was too viscous.
Thanks for the updates guys! Good to hear from you.
I dug out the Delphi MKIII today and couldn't for the life of me find the original PS. Buggar. So I found another 12VAC walwart @1.0A and fired it up and the motor would just sit there and wiggle back and forth. Gave it a spin and it wouldn't go. Gave it a few more wiggles and away it went. Not sure what it's problem was but it seems okay now. I am going to dig into the internals and find schematics for the guts of the controller and at a minimum, build up a nice heavy AC supply to feed the table, and maybe build up a new controller, depending on how the motor is driven. I will have to find a way to get into the motor casing. I didn't spend enough time on it today.
More later.
Cheers
I dug out the Delphi MKIII today and couldn't for the life of me find the original PS. Buggar. So I found another 12VAC walwart @1.0A and fired it up and the motor would just sit there and wiggle back and forth. Gave it a spin and it wouldn't go. Gave it a few more wiggles and away it went. Not sure what it's problem was but it seems okay now. I am going to dig into the internals and find schematics for the guts of the controller and at a minimum, build up a nice heavy AC supply to feed the table, and maybe build up a new controller, depending on how the motor is driven. I will have to find a way to get into the motor casing. I didn't spend enough time on it today.
More later.
Cheers
Ticknpop asked why a 12VAC supply rather than a 27VDC like he has on his MKIII. Very good question. I found several posts and pics indicating that the original was a 12VAC 1.0A supply.
Here is a picture I found for a MKIII, according to the ad.
So who out there has a MKIII, and what is your external PS rated at? Any pics?
Also, has anyone found schematics for the epoxy module under the motor? I am about to tear into mine and thought it would be good to know what I am getting into beforehand.
Cheers
Here is a picture I found for a MKIII, according to the ad.
So who out there has a MKIII, and what is your external PS rated at? Any pics?
Also, has anyone found schematics for the epoxy module under the motor? I am about to tear into mine and thought it would be good to know what I am getting into beforehand.
Cheers
Attachments
Happy to have found this thread... new MkIII owner (clean looking, but appears to have made the rounds ... the turntable, that is). Unit came with an obviously non-stock 800mA 12VAC wall wart, but it spins. Need to check speed and stability(may be an issue), obtain an arm/board, and sort out the suspension. Suggestions/opinions are welcome.
-dave
-dave
Hi Dave,
Welcome! Maybe we can work through our restorations together here in cyberspace. I tried mine again today after lubing the motor and it wouldn't start spinning again...just sat there and wiggled like it didn't know which way to go. I unplugged the AC, pulled the motor plug off the circuit board, put it back together and now it works. I think I may have to reseat the wires in the Molex connector.
I have pulled the springs out of their pods, but have not begun any tuning. I want to make sure I have a functioning motor first.
I have 5 different arms to potentially use, and I welcome any input from others who have had experience with any of these arms. I also have a variety of cartridges to match with the various arms...but that is a new thread.
1. Fidelity Research FR-64fx
2. SME 3009 Series II
3. Audio Technica AT-1005MKII
4. Rega RB300 (currently on it)
5. Syntec S-220
Your thoughts? What would be the best bet for this table? I know it's a tough question, and maybe there is no one correct answer.
Keep us posted on your progress.
Cheers
Paul
Welcome! Maybe we can work through our restorations together here in cyberspace. I tried mine again today after lubing the motor and it wouldn't start spinning again...just sat there and wiggled like it didn't know which way to go. I unplugged the AC, pulled the motor plug off the circuit board, put it back together and now it works. I think I may have to reseat the wires in the Molex connector.
I have pulled the springs out of their pods, but have not begun any tuning. I want to make sure I have a functioning motor first.
I have 5 different arms to potentially use, and I welcome any input from others who have had experience with any of these arms. I also have a variety of cartridges to match with the various arms...but that is a new thread.
1. Fidelity Research FR-64fx
2. SME 3009 Series II
3. Audio Technica AT-1005MKII
4. Rega RB300 (currently on it)
5. Syntec S-220
Your thoughts? What would be the best bet for this table? I know it's a tough question, and maybe there is no one correct answer.
Keep us posted on your progress.
Cheers
Paul
Found the fix for weird speed problems
An update from the front.....
I found the speed problem with my MKIII and wanted to share so maybe some of you out there with similar problems, might be able to fix yours.
Under the power supply cover, there is an epoxy potted module that drives the motor. The motor is connected with an AMP connector and when my motor decided to do the wiggle dance, like it couldn't decide which way to turn, I moved the plug and shazam..it started right up and kept spinning. I cleaned the pins and reseated the wires in the plug, then it stopped working altogether. So I thought there must be a cold solder joint on the board and proceeded to cut away little chunks of epoxy off the top of the connector and got down to the plastic housing of the connector, and there were already little cut outs for testing, so I put on my SMT soldering tip and reheated each connection. Tried it again and it works 100%!! Don't try this with a Weller gun, it just won't work. You need a really fine tip to do this.
Anyway, just thought you would like to know a possible fix for your MKIII speed issues.
Cheers
Paul
An update from the front.....
I found the speed problem with my MKIII and wanted to share so maybe some of you out there with similar problems, might be able to fix yours.
Under the power supply cover, there is an epoxy potted module that drives the motor. The motor is connected with an AMP connector and when my motor decided to do the wiggle dance, like it couldn't decide which way to turn, I moved the plug and shazam..it started right up and kept spinning. I cleaned the pins and reseated the wires in the plug, then it stopped working altogether.
So I thought there must be a cold solder joint on the board and proceeded to cut away little chunks of epoxy off the top of the connector and got down to the plastic housing of the connector, and there were already little cut outs for testing, so I put on my SMT soldering tip and reheated each connection. Tried it again and it works 100%!! Don't try this with a Weller gun, it just won't work. You need a really fine tip to do this.Anyway, just thought you would like to know a possible fix for your MKIII speed issues.
Cheers
Paul
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