I'm sure most of you who have had to replace the Jalco 3-terminal Mono PCB mounted phone jacks on Roland JC120's (and others), and have the plastic bushing just break right off while tightening the metal nut on the threaded bushing. That's where this current project began. I was out of the replacement jacks (lately using a Kobicon part purchased thru Studio Sound Electronics for $4.95 ea + shpg, plus extra for the nut/washer).
When I swapped out the two Jalco original parts on Ch 2's input board with the new Kobicon parts, one of the two jacks just didn't want to allow the nut to thread back on. I tried different nuts, with repeated tendency to want to cross-thread, which they will do with the greatest of ease. I finally removed the board to have a closer look. That's when I saw the defect in the injection molded part:
If you look close at the thread pattern of the lower uninstalled jack, you can clearly see the threads on the upper half are completely misaligned with the lower half. The upper jack was the one that repeatedly wouldn't accept the nut, and it began buggering the thread. So, I had to remove that jack, looked thru the remainder of the 6 pcs I just received, to find one more (with the same defect). First time I've run into this.
I'm NOT a big fan of the Jalco jack, as the threads stop before they reach the body of the jack, and there's actually a void, which is where the bushing breaks off with the greatest of ease when attempting to tighten the loose nut again.
Studio Sound Electronics has responded by sending replacement jacks, so hopefully that will solve this for the time being.
When I swapped out the two Jalco original parts on Ch 2's input board with the new Kobicon parts, one of the two jacks just didn't want to allow the nut to thread back on. I tried different nuts, with repeated tendency to want to cross-thread, which they will do with the greatest of ease. I finally removed the board to have a closer look. That's when I saw the defect in the injection molded part:
If you look close at the thread pattern of the lower uninstalled jack, you can clearly see the threads on the upper half are completely misaligned with the lower half. The upper jack was the one that repeatedly wouldn't accept the nut, and it began buggering the thread. So, I had to remove that jack, looked thru the remainder of the 6 pcs I just received, to find one more (with the same defect). First time I've run into this.
I'm NOT a big fan of the Jalco jack, as the threads stop before they reach the body of the jack, and there's actually a void, which is where the bushing breaks off with the greatest of ease when attempting to tighten the loose nut again.
Studio Sound Electronics has responded by sending replacement jacks, so hopefully that will solve this for the time being.
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