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N_Cook N_Cook is offline
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Default Fender Bassman 250 , PR597, 2005

spamtrap1888 wrote in message
...
On Aug 1, 3:27 am, "N_Cook" wrote:
I expected some no-name Chinese make but no , it is Neutrik with this

crappy
design.
Reassembled preamp with the socket exposed and it was then obvious there

is
a third way to loose ground contact. There is no sprung contact to the
sleeve of the jack , just rests on the chromed barrel , relying on the
spring contacts of the tip and ring to supply pressure to keep the sleeve

in
contact with the inside and innermost small segment of arc of the chromed
barrel . Even without WD40 , corrossion and general crud , because of the
lever action, it takes very little upward force on the jack, at the cable
end , to lift the sleeve and break contact.

So failure mechanism probably went like this.
Bad ground contact due to slack nut. Instead of tightening, owner squirts
WD40 in there which
pools in the lower surface of the barrel , collects crud, congeals etc.
Eventually he tightens the nut , but by then its too late. A get by , on

the
road, solution to this would probably be some sort of reaming action

inside
the bush barrel


You are replacing the socket with one that has spring-loaded contacts,
right?


+++++
and with plastic barrel and added star washer wired-in. You can then have
something like an interference fit between jack and barrel , so little or no
play in any off-axis direction. Because the Neutrik is metal and metal there
has to be a clearance fit and so its easy to break the sleeve contact.

Another problem in waiting. One of the o/p TOP3 the thread on the
alumininium "heatsink" block was stripped , presumably at production, not
loose but could not take any normal tightening force. Had to fashion up a
spring clip instead of the thru bolt