DOD FX 20 PHASOR LED and input jack issue

Started by Iffy Jiffy, June 30, 2022, 02:55:37 PM

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Iffy Jiffy

Hi, I have a DOD FX 20 Phasor that I am trying to get working again. This has been put down for a while. The issue I am having is with the input jack. If I push the male 1/4" jack all the way in, the LED does not come on but when I pull it back out a bit the LED illuminates. The switch has no effect when pressed and does not turn off or on the LED.  The contacts in the switch were corroded and I cleaned it, and the switch works when checked for continuity with a multimeter. I also have other new tactile switches that I have tried and the same result. There is really not much to the input jack. It has three contact points, ground, tip and the other that activates the LED when the male jack is inserted. I have dealt with a similar issue in the past and cannot remember what I did to correct the situation. There may be other issues with the pedal, but I need to get the input jack sorted out first before I can go any further. Usually with a pedal this old I prefer to replace all the electrolytic caps regardless of if they test good or not. I only have a capacitance tester so I cannot check the ESR.  Also, I resoldered the contacts in case there may be any cold solder joints.
I would like to hear any suggestions as to what the problem could be and how to resolve it. Any input would be appreciated.

Fender3D

Ring contact on input jack switches battery negative to ground.
Replace input socket, it will be easier than check each capacitor on board  :)
... unless you're using a stereo jack plug....
"NOT FLAMMABLE" is not a challenge

ElectricDruid

Quote from: sammyadam on July 04, 2022, 07:21:40 AM
Does anyone make a power supply daisy chain for those 'oddball' 1/8 power jacks, or am I gonna hafta make one myself?

Honestly, the best thing to do is to remove it, drill the hole out larger, and fit a plastic-bodied 2.1mm socket so that the pedal is the same as everything else on your board. 1/8 power jacks are just a pain in the ar53!

duck_arse

the spammers don't care about hole sizes, not really.
You hold the small basket while I strain the gnat.

Mark Hammer

1/8" phone jacks for power "work", but the issue is that power has to be off before inserting the plug into the pedal, or else you'll get a disconcerting spark when you got to insert the plug and the tip and shaft momentarily short out as they touch the outer part of the jack.  Despite all their other virtues (i.e., smaller size, ease of installation, good connection, and assurance that tip is always positive), I think this is why the industry began moving away from their use for power jacks.  As much as you can lead a horse to water, without getting it to drink, you can tell customers a hundred times over "Insert plug before turning power on", and they'll still forget.  The issue becoems even more problematic for use of daisy-chain cables, since people will think "I'll just add this other pedal..." without turning the power off.

Get yourself a reamer, and bore out a larger hole for a barrel/2.1mm jack.  There are two types; what I like to call "innie" and "outie" (like belly-buttons).  You'll want an "outie" since it will be easier to install and take up less interior space than an innie.

Here's what innies look like:

And here's what outies look like.  The nut is tightened from the outside of the enclosure.  A LOT easier.:

Fender3D

Sorry guys, isn't he talking about 1/4" input jack?
"NOT FLAMMABLE" is not a challenge

bluebunny

Quite correct, Federico!  8)

Quote from: Iffy Jiffy on June 30, 2022, 02:55:37 PM
The issue I am having is with the input jack. If I push the male 1/4" jack all the way in . . .
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