help with magnavox cdb 650 please!

Discussion in 'Digital Sources' started by bobbyonions, Jan 13, 2011.

  1. Dr Tinear

    Dr Tinear AK Subscriber Subscriber

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    I did the upgrade in 1992 or 1993 and didn't take notes, so I don't recall the details of the job. I'm pretty sure that I used the AD827JN, which is the 8-pin plastic DIP package. The parametrics on the standard-grade device were more than good enough for the application, so I didn't see any need to spend more money on the commercial or military temperature grade or the ceramic DIP package. This many years after the job, I can't tell you which caps got changed out.
     
  2. nbndtrain

    nbndtrain Active Member

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  3. bobbyonions

    bobbyonions AK Member

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    Thanks folks. For those interested, I figured out why the player was sometimes not reading. As I mentioned, sometimes when a cd was loaded the player would take it in and it would just spin at full speed and show an error message. When the cd was ejected, the tray would pop out with the disc spinning full speed. in the tray.
    The last time it did this, I started chopsticking around the boards while the cd was stuck in the spin mode. When I pressed on the 14-connector harness that goes from the servo board to the main board, the player suddenly read the cd and began functioning as normal. I was able to repeat this after it again refused to read later that day, so I was pretty sure I had found the problems area. I removed , cleaned and deoxed the connector, and it's been playing beautifully ever since, which has been daily for a week or so. Does this add up?
     
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  4. dr*audio

    dr*audio Fish fingers and custard! Subscriber

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    I have one sitting in the closet. I was not aware of that problem with the connector. I'll have to try that on mine.
     
  5. dukethejuke

    dukethejuke New Member

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    Location:
    sykesville md
    great thread

    I am finally getting back to audio fun, and I cannot wait to try this mod. I have always enjoyed the sound of the Magnavox. My friend bought one of the first one sold at Hecht co. that is right a box store. It was the FD1000 and sold for a 1000 bucks. I bought the next generation "slyvania" $335.00. Side by side nothing touched this unit. I thought that the swing arm had alot to do with the sound as apposed to the gear driven tanks Sony put out. Again thanks for the thread!




    McIntosh C20 preamp, Dynaco MarkIV's, Maggies IIa's, Fried model H sub, Carver M200t, Marchard XM9 crossover, Celestion Ditton 250's Magnavox cd player
     
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  6. STLABC

    STLABC New Member

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    Just spent some time tinkering with my Magnavox CDB650 and was able to get it working again based, somewhat, on information from this thread.

    Symptoms were ......

    1) Disc would spin for varying lengths and then suddenly stop and display an error message.

    2) The spinning also created a slight rubbing/abrasive noise that stopped when the spinning ceased.

    A slight touch of the swing arm with a Qtip was met with a very slight resistance and then it swung freely.....after that no noise and works great. I suppose I should clean/lube that swing arm somehow......any thoughts?
     
  7. sloober

    sloober Super Member

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    I've had this player since I bought it new in 1986-7. I just dug it out and did the condor audio mods. I ordered a kit with all caps and new opamps. Damn does it sound good now!
     
  8. Dave W

    Dave W New Member

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    Palm Springs, CA
    Hi. I'm new here, and I am dealing with a sticking drawer on a CDB650. Where can I find a replacement drive belt, and what is the most direct means of accessing it?

    Thanks
     
  9. Dr Tinear

    Dr Tinear AK Subscriber Subscriber

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    I've seen this problem before on a CDB-650 and can tell you that it has nothing to do with lubrication. The flex circuit from the laser head to the data separator routes through a channel in the white plastic disc drive base plate. The counterweight for the swing arm rotates through that same channel. There's a black plastic clip that holds the flex circuit at the bottom of the channel so that the counterweight can't contact it. If that clip works loose, the flex circuit shifts upward in the channel and contacts the counterweight, causing a hitch in the swing arm's rotation. You can fix the problem by pressing on the loose clip until it snaps into place and gently rotating the swing am by hand to make sure that it moves freely without rubbing against the flex circuit.
     
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  10. marc brown

    marc brown AK Supporter

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    Thanks for adding closure to this thread. I always hate when I have a problem similar to one in a thread and the thread just dies with no resolution. lol
     
  11. kwingylee

    kwingylee Active Member

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    Location:
    Chicago, IL
    Just acquired a Phillips CD650, I am having the same symptoms as described here. It refuses to read disks. How did you guys get to the "clip" mentioned? Is the servo board beneath the drive? How did you guys remove the drive? Thanks in advance. I am hoping this is the solution.
     
  12. tonyd_

    tonyd_ New Member

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    Location:
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    * * * * * * * * * * * * * * * * * * * * * * * * * * *
    Dear 'Dr Tinear', (Wed, 5Apr17, ~4:30PM EDST), I found this input from you, and am kindly going to ask your help (please) in fixing my Magnavox CDB650 CD player (1986/Made in Belgium). When cold, it will run fine up through (about) ~ the 4th track. After that, the tracking (or focusing) mechanism begins to emit a high pitch whine, not real loud, but noticeably louder to one pressing the player's button(s). It will play perhaps one or a few more tracks this way (whining), until it very suddenly suddenly stops, the tracking swing arm/lens/head returns home, and the display shows the disc's table of contents (as when initially loaded). The problem ameliorates with run (play) time, as the player warms up, and the whine occurs further out on the disc's outer tracks. I can tell the machine will stop playing at almost any time, when I begin to hear the said whine (not real loud, but noticeably louder than the spindle's drive motor, an much higher pitch). I've taken the cover off, gently dry brushed the lens with a lens brush, and it looks fairly clean. (Have not cleaned with compressed air as of yet). The swing arm does move freely across its complete travel distance. And, I can gently push down on the lens and it does go down into the head and springs back up just fine. The player does not have excessive amount of play hours. I have modified it's output stage with better coupling caps. (It sounds very nice to me, through my speakers). And thus, would like to keep it. In regards to your recommendations to the member ('bobbyonions') who asked for help regarding his Magnavox CDB 650's disc read issues. I hope that you can give me some help and advice regarding this my player. (I like this player, as my dad and I worked on it together back when we still had him here). Thank you very very much in advance.
    Thankfully and Respectfully, tonyd.
     
  13. markuus3889

    markuus3889 Diatom, what's that?

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    Hi Tonyd,

    The 33uf capacitor #2103 on the board under the laser assembly, is a known problematic component. The condoraudio link above to the cdb650 has a brief description and pictures at the top of page 5. A 650 manual can be had for free although not in English. I wish I could help more but I am new to this stuff too. Hopefully someone more knowledgeable will come along. The laser assembly is a CDM2.

    Good luck,

    Mark K.
     
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  14. tonyd_

    tonyd_ New Member

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    Hello Mark K. Thank you so much for the reply. (I'm delighted). Thank you for the information. I appreciate it very much. God Bless your home. tonyd.
     
  15. markuus3889

    markuus3889 Diatom, what's that?

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    You are welcome and I sincerely hope you have success!

    Mark K.
     
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  16. tonyd_

    tonyd_ New Member

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    Thank you again, Mark K. God Bless. tonyd_
     
  17. onanysunday

    onanysunday AK Subscriber Subscriber

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    Location:
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    Thank you for this reply Dr Tinear. It just completely fixed my Magnavox CDB650 after I had done extensive refurbishment on it and it would not play past track 5 because it had been opened by a previous owner and they did not put the ribbon cable back in properly with the black plastic clip that holds it in place. The laser was hitting the ribbon cable once it got past that arc around track 5, so thanks again! It is now on an equal footing with my heavily modified Rotel RCD-855 that I just modified. Terrific thread.
     
    Last edited: Oct 10, 2017
  18. onanysunday

    onanysunday AK Subscriber Subscriber

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    Just a quick note to anyone working on this unit, every single blue "Philips" axial electrolytic capacitor on every single board was completely out of spec, some having lost capacitance up to 80% of the original value with extremely high ESR around 5-10 ohms per cap. For anyone working on this player please replace all the blue axial electrolytics if you haven't already, they are all completely out of spec at this point.

    I tested and replaced every single capacitor on this Magnavox (except main power cap) and only these blue capacitors were the ones out of spec for the most part. This advice also applies to anyone working on any other Magnavox CDB player that uses the house branded axial blue capacitors. Test them for yourself and find out, they are all garbage by now and huge gains can be heard by removing and upgrading them to Panasonic FM or something similar.

    By the way, does anyone know a good replacement for the main Philips power cap on these CDB players? It is a 6800 uf 16V 4 pin radial capacitor. It has aged quite nicely still being 99% within rated capacitance, but I was curious about replacing it with something of a slightly higher voltage with lower ESR and higher ripple current as I have done with all the other capacitors in the power section..
     
  19. markuus3889

    markuus3889 Diatom, what's that?

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    Location:
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    I think Nichicon UBY 25Volt 10000uf High temp are good. Work well in my cdb560 and RCD855.

    Good luck,

    Mark K.
     
  20. ferninando

    ferninando AK Subscriber Subscriber

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    I recently got a Mag CDB 560 and assume the mods mentioned can be applied to it as well.??
    Am I correct?
    thanks.
     

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