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A couple days ago, when I moved my Symetrix SX202 half-rack size dual Mic Preamp over to the Lombardi Mixer I've been restoring, I found both gain pots and the pushbutton switches all extremely noisy, in need of cleaning.
Today I pulled it apart, desoldered the two pots, pulled them apart to clean the resistance tracks, put those back together. Then, seeped Caig contact cleaner down both sides of the shaft to seep into the contacts of the DPDT push button switches and exercised them good, along with the pots. Put the PCB back into the chassis, put the recessed sub-panel back into place, put the rear cover back on, which is held in place with the recessed latches of the Female XLR connectors. Mounted the pot hardware, adding the 7mm flat washers that were missing, tightened those up. Seemed like I had to tighten the bushings more. Put the knobs back on, put the front panel on. I found the pots didn't want to rotate smoothly, though they did when I had reassembled them, as well as after soldering them back into the PCB.
I then found there was a gap between the cover and the front panel, and that wasn't like that when I pulled it apart, so disassembled it to see how I messed up.
I messed up BIG TIME. I removed the sub panel, and with it came the body of the two pots, while what was left on the PCB was the broken substrate of those two pots, nicely soldered into place!!
OH, HOW DELIGHTFUL!! Pulled up the schematic, knowing these were PC Mount Noble Reverse Log taper pot. 2.5k, 16.5mm dia body, 7mm threaded bushing, 6.5m long, 18mm overall from mounting boss, Single-D shaft. 12.5mm pot c/l to PCB surface, 5mm PCB terminal spacing. What's the chance of finding some of these? Checked Mouser, and nothing available but a 10k Bourns.
Checked Digi-Key, and found, to my total amazement a TT Electronics P160 Series 2.5k Rev Log PCB mount pot, EXACT form-fit-function to what I just broke, IN STOCK, $0.85 ea! Placed the order, PayPal, all the info in my account was correct. Though while placing the order, where I'm used to having the order process send me to my PayPal account to authorize it, that step didn't happen, but all else went thru, got all the order ID, everything else.
This sounds too good to be true, making a stupid mistake as I did, totally breaking both pots, and finding exact FORM-FIT-FUNCTION replacement pots for it.
Today I pulled it apart, desoldered the two pots, pulled them apart to clean the resistance tracks, put those back together. Then, seeped Caig contact cleaner down both sides of the shaft to seep into the contacts of the DPDT push button switches and exercised them good, along with the pots. Put the PCB back into the chassis, put the recessed sub-panel back into place, put the rear cover back on, which is held in place with the recessed latches of the Female XLR connectors. Mounted the pot hardware, adding the 7mm flat washers that were missing, tightened those up. Seemed like I had to tighten the bushings more. Put the knobs back on, put the front panel on. I found the pots didn't want to rotate smoothly, though they did when I had reassembled them, as well as after soldering them back into the PCB.
I then found there was a gap between the cover and the front panel, and that wasn't like that when I pulled it apart, so disassembled it to see how I messed up.
I messed up BIG TIME. I removed the sub panel, and with it came the body of the two pots, while what was left on the PCB was the broken substrate of those two pots, nicely soldered into place!!
OH, HOW DELIGHTFUL!! Pulled up the schematic, knowing these were PC Mount Noble Reverse Log taper pot. 2.5k, 16.5mm dia body, 7mm threaded bushing, 6.5m long, 18mm overall from mounting boss, Single-D shaft. 12.5mm pot c/l to PCB surface, 5mm PCB terminal spacing. What's the chance of finding some of these? Checked Mouser, and nothing available but a 10k Bourns.
Checked Digi-Key, and found, to my total amazement a TT Electronics P160 Series 2.5k Rev Log PCB mount pot, EXACT form-fit-function to what I just broke, IN STOCK, $0.85 ea! Placed the order, PayPal, all the info in my account was correct. Though while placing the order, where I'm used to having the order process send me to my PayPal account to authorize it, that step didn't happen, but all else went thru, got all the order ID, everything else.
This sounds too good to be true, making a stupid mistake as I did, totally breaking both pots, and finding exact FORM-FIT-FUNCTION replacement pots for it.
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