Conference hips::uk_audioo

    Hello Alan,
    
    Have you checked the Bias compensation device to see it's set correctly
    for the weight of the cartridge?
    
    Tim

Tim

 I would do if I knew what it is !! So basically the answer is no.

		 Alan
		~~~~~~

    I had an old Mk II SP25 inherited from a really old (early 70s) HMV
    stereo unit. I think it developed the same problem you have. I don't
    think it was anything to with bias compensation (mind you I never did
    fix it...).  There was a definate (if only slight) 'sticking' of the
    arm at a particular point towards the centre of the deck that suggested
    something mechanical, rather than a setup problem.
    
    The auto-pickup broke as well, so I gave it to my brother.
    
    Paul
    
    

Try taking a look below the top plate, where the armtube wires come out of the
arm.  There's probably a loop of wire that should move freely as the arm moves
across the record.  Check that this loop isn't fouling against anything.  Even
the gentlest contact with nearby parts will affect stability.

Nick

Ah!  Automatic armlift at end of side!  (I can barely remember the SP25.)  If
it senses end-of-side mechanically, the problem is *much* more likely to be
something associated with the sensing than with the armtube wiring - you could
probably wire it up with mains cable before the wiring affected it.  See if
there's any gunge around the armlift mechanism, particularly where it interacts
with the arm.

Nick

    Oh! Happy Days! The SP25 (MkII) was my very first "Hi-Fi" deck.
    
    From memory, the areas to look at are:--
    
    1. The lifting mechanism, which has a little curved plate near the 
    arm pivot, and an adjustable pin to give the lift. Check that 
    there is clearance throughout the travel, no hardened gunge or 
    grease giving lift near the end.
    
    2. Definitely check the pickup wires where they exit under the 
    baseplate. If they have any restriction, or are twisting too 
    tightly, they could cause the symptoms.
    
    3. The 'auto lift' at end of play. This is driven by a huge cog 
    under the baseplate. It is usually smothered with a beige grease, 
    which sets rock hard over the years. Clean it all off, reapply 
    light grease (Vaseline etc.) and cycle it through a few times.
    
    To check these, you need to lift out the deck, so while you are at 
    it, 'eyeball' everything else underneath for obvious problems. 
    When refitting the deck, make sure that the three spring 'shock 
    mounts' go back into the circular depressions in the base, and 
    that the arm wires aren't catching on the baseboard. 
    
    If all else fails, try looking round second-hand and junk shops. I 
    bought an SP25 MkV complete with good condition Shure M75 for my 
    kids' school about 2 years ago. I haggled it down from �7.50 to 
    �5.50, and it's still going strong!
    
    Mike in Warrington.

re .6:

Don't use Vaseline as a lubricant.  It isn't one.  It creeps away from the
points of contact and permits scraping and wear.

Bog standard grease like Castrol LM might do the trick.

Nick