RuF wrote:
> Hi Experts,
>
> I have finally managed to get my 1219 going again, this time with a new
> Shure M97xE.
> It feeds into a Sony STRAV260 amplifier via RCA cables.
>
> The right channel is working fine but the left one has a very weak
> output. I swapped the
> RCA connectors at the amplifier and output behavior also swapped, so the
> problem is at the turntable.
>
> Under the turntable there are four connector prongs beside the muting
> switch. Two of the connectors are between one and two inches above the
> others. The pair closest to the axis of the turntable are attached to
> ends of the RCA cables. One of the other prongs has nothing connected
> and the fourth prong is connected to a ground lead that goes to the
> amplifier case and to the ****elds of the two wires that carry the output
> from the cartridge.
>
> Without taking the arm off, it's not easy to see into that area under
> the shell. Is it likely that there is a bad contact there?
>
> Comments appreciated.
>
> RuF
RuF,
It is possible that the muting switch is causing the problem, but not
the first thing I'd suspect.
Dual used among the worst RCA cables in existence, so if you have not
already tried new ones, I would. The factory ones used crimped
connections, and the grounds commonly go bad causing hum and bad
connections.
There is a similar problem with the head shell leads These can be
resoldered, but you have to be VERY careful not to damage the head shell
contacts. Both the cartridge and head shell ends of the 4 wires are
suspect. You might want to consider a new head shell if they are still
available. A new old stock head shell may have the same problems as
your existing one, as the crimps have been around for many years.
The contacts in the arm itself, where the head shell connects can often
be corroded. Don't use a rough abrasive, as you'll remove the plating.
I'd start with a cotton swab moistened (not dripping) with a contact
cleaner. Do the head shell side of things too. I would then use a dry
q-tip to remove as much of the cleaner as possible. To be really
residue free, you could clean with alcohol.
Of course, first start by being sure that the head shell leads are all
going to the right places, and make sure the lugs going onto the
cartridge pins are snug. If they are loose, squeeze them GENTLY with
needle nose pliers or tweezers to tighten them up a bit. Be careful, if
you over-tighten them, then they won't fit the pins on the cartridge any
more. They can also break.
Lastly, are you sure that the new cartridge is good? If you have an
ohmmeter, then measure the left and right windings of the cartridge.
The readings should be similar. This needs to be done with the head
shell removed from the turntable, but the cartridge can still be mounted
in the head shell.
Regards,
Tim Schwartz
Bristol Electronics
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