Information, Tips and tricks, schematics and How to... for Otari MX5050 series recorders

Bookmark this page.... new material added from time to time !!!

this page is not fully completed yet.... just started on it!! Some Areas have info pages so go looking around!


   
our current OTARI parts list

    OTARI   MX 5050    
  tape recorder parts for sale  


 

    Otari pics and vintage Sales Brochures

 

  Otari Pics and Sales Brochures  

 



    Otari I-0012 IC


the Otari I-0012 ICs in the 5050 machines   !!!




   
Is my 5050 machine Balanced or Unbalanced ?


5050's - some are Balanced some are Not !



 
5050 Tips and Info


How many 5050 2 track versions are there ???

the 5050 (no other tag)   •   Mini-Pro   •   2S   •   2SHD     •   4S   •   QXH   •   'Mark II'   •  
      •   B   •   BII   •   BII-2   •   B2   •   BIII   •   BQII   •   BQIII   •   mkIII   •   mkIV   •  and likely more !!!  



You MUST lubricate your capstan motor upper bushing often !!!
One of the major causes of capstan failure is lack of lubrication.
So make sure you've got the proper special OTARI oil and use it every few months !!!
  Do NOT use regular oil !!!
 
You can purchase the correct Oil at Athan Corp.   :
     Otari capstan Oil  

 

Instructions for Lubricating your 5050 capstan motor...



Never put more than a drop or two of oil into the capstan !!!
Over-oiling can actually freeze the capstan shaft to the upper bushing !!!


Otari 5050 series capstan motors are all slowly going bad...
usually lack of lubrication as noted above...
or just wear, but also over time, the drive coils can work their way off their
mounts and fall into the turning rotor of the motor, causing it to freeze up.
 
So if you begin to hear a ticking sound inside the motor itself - you can check this
by just spinning the capstan shaft by hand - DO NOT TURN THE MACHINE ON again!!!
 
You will immediatly need to send the motor to a good tech who then can see
if the motor coil can be reset in place, or replace the coil if it is damaged.
Running the capstan with a loose drive coil will at best cause severe
Wow and Flutter, at worse destroy your motor.     And new replacement
Capstan Motors are expensive to find,   good used ones also hard to find as
almost all used ones are worn out and need rebuilding.
Rebuilding a capstan motor costs about $ 350.00
 
 


s
 
Finally you need to Exercise ALL the switches on your machine often   !!!!
Switches like the speed switch, the servo pot/switch, the rear switches,
usually do not get much action... and they can get dirty, corrode, or
become Intermittent over time from just not being used.     So just
switch each of the switches back and forth a few times every month.
 

NEVER, NEVER, NEVER work on anything electronic
without disconnecting the AC cable from the AC power socket !!!


You MUST remove ALL power connections before opening up anything electronic !!!


Note that the Original Otari 'Power On-Off', 'Speed'. 'Reel', and 'Edit' switches
for the BII and other versions are no longer made and NO direct replacment is available...
There is internal lubricant inside these switches which alas gets gunked up
over time and solidifies.... which will make one of these switches intermittent
or just not work at all.     You can take off the metal plate covering the
switches, first disconnecting the AC power cable of course, and try and spray clean
the switch by spraying LPS1 Greeseless Lubricant down the shaft of each switch,
with the machine laying on it's back, then pressing the switch about 20 times.
this will work about 50% of the time.    
If this does not work for you, then you will need to bring the machine over
to a GOOD EXPERIENCED tape machine tech and have them try and rebuild the old switch,
which alas is NOT easy to do !!!

 



 
If the machine has not been in use for a month, turn her ON
and hold the Tape-Break arm up in normal position with masking tape,   and press Play...

    This will set the motors in motion, exercise the Pinch Roller Solenoid,
and help keep your machine in good running condition.... without running tape on her.
 
Run her this way for 5 minutes once a month if she's sat unused for a while.
 



A lot of folks have burnt out VU meter lamps in their 5050 units.....
These can easily be replaced.... BUT.... the original lamps are hard to find.
The original Otari VU meter lamps have FROSTED GLASS and thus defuse the light well
while replacement lamps are clear glass and thus have hot spots of light,
which alas do not look very good.
 
Apparently these frosted glass lamps are no longer being made.
... no exact replacment lamps.


 
There are 4 basic versions of the Otari 5050,
and some variation in each basic version.... usually depending on how
many tracks the tape recorder has... 2, 4 or 8 tracks, and the age of the design.
 
You want to AVOID the first versions...


      the  5050 no version #  (silver face audio electronics)
      the  Mini-Pro  (silver face audio electronics)
      the  2S  (silver face audio electronics)
      the  4S  (silver face audio electronics)   quarter track
      the  2SHD  (silver face audio electronics)
      the  QXH  (silver face audio electronics)
      the  Mark II  (black face audio electronics)
      the  B  (black face audio electronics)
      the  BII  (black face audio electronics)
      the  8D  (black face audio electronics -2 piece)
      the  8SD  (black face audio electronics -2 piece)
pics shown below:
 


   


These early versions have the RECTANGULAR Record Ready buttons on the left
side of the electronics....   later (much better) versions have square Record Ready buttons.
 


 


The early versions had a poorly designed tape lifter system that
wears out quickly and will allow the tape to touch the heads
in the wind modes.... thus wearing out heads fast.    
I've had to do various mods and such to get the tape lifters to move tape
off the heads, but these are hard to do and costly....
Plus Some of the EARLY 5050's - the BII versions - used an oversided 14 pin DIP IC as the
Audio Output driver....       Otari part # ICH571C (uPC571C)
that is obsolete and near impossible to find.   When it goes bad,
it will be costly to mod the machine to take another IC in its place....
Plus the early versions had audio relays that have a strange size and are no longer made...
So just avoid the Otari MX5050 BII versions.



      NOTE:  a 5050   BII   is NOT the same as the 5050   B2   !!!  


Note also there are many different model numbers - Versions that are all using
the basic style of the 5050 transport and look about the same, though the
internal electronics are slightly or greatly different !!
 
 Also as I recall ALL the early versions have mechanical Counters.


Otari Corp 'Refirb' Special Pricing - from 1996     !!!!



  OTARI Manuals:
 

    OTARI Manuals are now listed at:    
  AnalogRules.com   Free Manual List  



 

 



    HOME      CONTACT US      RESOURCES      HOW TO      Tips 'n Tricks      FAQ