Tim Schwartz wrote:
> 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
Thanks Tim.
As you suggested I cleaned up all the contacts near the
pickup and then reinstalled
but it didn't do any good. Next I tweaked the contacts at
the rear of the shell and reinstalled.
That did the trick. Thanks again for your help.
RuF.
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