Author Topic: Polarity on BLMS thinline DC jacks?  (Read 752 times)

vizcities

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Polarity on BLMS thinline DC jacks?
« on: June 06, 2019, 08:46:33 AM »
This is more a reinforcement question, but: what is the polarity on Love My Switches' generic thinline DC jacks?

https://lovemyswitches.com/thinline-2-1mm-dc-power-jack/

Looking at the Lumberg build doc elsewhere on the site, it looks like their long lug is + and short lug is -. However, the doc Lawrence provides for the cheap equivalent (that is, the version I have) is confusing, and I'm not clear if it's a 1:1 clone. My only experience wiring the jack thus far was for a Punch Amp build: going from a DIY Stompboxes thread, I wired it as noted above and ended up cooking an IC. After replacing the IC and switching to a battery pack, it was fine, but I'm now a little gunshy about using another cheap thinline. Before trying again, I just want to make absolutely sure the issue wasn't reversed polarity.

EBK

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Re: Polarity on BLMS thinline DC jacks?
« Reply #1 on: June 06, 2019, 09:03:14 AM »
Got a multimeter handy?  Sounds like you are nervous enough to want to at least double check even if someone gives you an answer, right?  ;)
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tcpoint

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Re: Polarity on BLMS thinline DC jacks?
« Reply #2 on: June 06, 2019, 09:59:28 AM »
The long lug is positive and the short lug is negative (assuming center negative).

flanagan0718

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Re: Polarity on BLMS thinline DC jacks?
« Reply #3 on: June 06, 2019, 05:51:09 PM »
Iíve been building for 5 years or so and every time I go to wire the DC Jack, regardless of what I think I know, I still plug in the DC cable and test the pins with my DMM. Iíve been fooled before by being over confident.
-Mike-


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mjg

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Re: Polarity on BLMS thinline DC jacks?
« Reply #4 on: June 06, 2019, 07:21:09 PM »
Iíve been building for 5 years or so and every time I go to wire the DC Jack, regardless of what I think I know, I still plug in the DC cable and test the pins with my DMM. Iíve been fooled before by being over confident.
-Mike

This is what I do too.  Before soldering it to anything, plug in the power, turn it on, check the polarity with a multimeter.  Then I mark the positive lug with red marker, because I'm likely to forget about 2 minutes later. 

vizcities

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Re: Polarity on BLMS thinline DC jacks?
« Reply #5 on: June 09, 2019, 12:23:53 AM »
Got a multimeter handy?  Sounds like you are nervous enough to want to at least double check even if someone gives you an answer, right?  ;)

This is indeed what I ended up doing. Thanks for reminding me - I sometimes get kind of lazy about utilizing my multimeter.