Sharp zaps/jolts while using DIY e-stim device?

[6ix5ive]

Hi all,

I put together a DIY e-stim device about a year ago and it's a fantastic little device, save for one flaw that prevents me from liking it more than my 2B.

During use at random times, I will experience an unpleasantly painful, very fast, high intensity, sharp zap/jolt. The duration of this 'zap' feels like 1/10th of a second, it's very quick and the signal returns to normal just as fast. It's intense enough that on a low, mild setting the surprise and pain of the 'zap' makes me jolt my muscles and kills the mood. In a session of let's say, 20 to 30 minutes, I will experience upwards of 20 of these 'zaps'. I like to have longer sessions and being subject to these painful shocks really prevents me from enjoying my device.

Things I've tried to remedy this problem are as follows (all have failed):

• Use Bluetooth audio input

• Use 3.5mm audio input

• Use phone as input device

• Use tablet as input device

• Use mp3 player as input device

If anyone can shed light on what may be causing these weird zaps it would mean a great deal to me. Any additional information you might want I will try to provide to the best of my ability. I will attach a shoddy schematic of my device and how it's components are wired to each other. Also if you have suggestions on components I could add, substitute or remove from my device that would also be highly appreciated!

Thanks!

[edger477]

I'd try changing power supply and double and tripple checking if the DC jack is loosing contact momentarily.

These amps often make zaps when power is disconnected/connected, and it seems you already done work investigating the audio side.

Also, I'd connect speakers to it instead of transformers and listen to music to see if it occurs.

[throwawayacct]

Check your volume potentiometers - touchy little things, and could be the source.

Troubleshooting flowchart dictates starting at the easiest checks and repairs first. As Edger said, plug into some speakers and test that way, to hear for the clicks/pops/skips/static.

[vaginalitch]

What you describes happened to me it was mostly caused by bad connection (i.e. one of the wires would come loose and then reconnect, causing abrubt spike) - more often than not caused by the jack cable between the amp and the pc.

[6ix5ive]

... double and tripple checking if the DC jack is loosing contact momentarily.

Mate I think you've hit the nail on the head with this one, I weighed the cable down to a table to stop movement, made sure the DC jack was seated properly, had the cable run straight with no bends and eliminated as much jack 'wiggle' as I could. There were no zaps to be found during a half-hour test run! I'm over the moon that the fix was seemingly as simple as it was, I was worried I'd have to buy yet another 6060-1 power supply!

Thank you to all who offered advice, y'all are the realest of the real!!!

Much love!

[edger477]

Mate I think you've hit the nail on the head with this one

I've recently got several kits to build NeoDK pulse box development kit... and almost killed one during flashing it because of that same issue, the power jacks have 5x2.5 and 5x2.1 mm versions and you can plug the jack with 5x2.5 into 5x2.1 socket and it will kinda work, but not reliably...

[Electro]

... double and tripple checking if the DC jack is loosing contact momentarily.

Mate I think you've hit the nail on the head with this one, I weighed the cable down to a table to stop movement, made sure the DC jack was seated properly, had the cable run straight with no bends and eliminated as much jack 'wiggle' as I could. There were no zaps to be found during a half-hour test run! I'm over the moon that the fix was seemingly as simple as it was, I was worried I'd have to buy yet another 6060-1 power supply!

Thank you to all who offered advice, y'all are the realest of the real!!!

Much love!

Sounds like perhaps it might only need surgery to replace the connector on either the power supply side or the amplifier side, or perhaps if the cable is bad that could be swapped; or perhaps the end cut off if you can hardwire the thing to whatever connection you have on the amplifier.

[6ix5ive]

Sounds like perhaps it might only need surgery to replace the connector on either the power supply side or the amplifier side, or perhaps if the cable is bad that could be swapped; or perhaps the end cut off if you can hardwire the thing to whatever connection you have on the amplifier.

The DC input socket on my amp has a slightly loose fit, it wiggles more than I'd like it to. If I were to do anything to my current setup I might buy a new socket and solder it in place of the old one, whilst fingers crossed the new purchase has a tighter fit!

[edger477]

Sounds like perhaps it might only need surgery to replace the connector on either the power supply side or the amplifier side, or perhaps if the cable is bad that could be swapped; or perhaps the end cut off if you can hardwire the thing to whatever connection you have on the amplifier.

The DC input socket on my amp has a slightly loose fit, it wiggles more than I'd like it to. If I were to do anything to my current setup I might buy a new socket and solder it in place of the old one, whilst fingers crossed the new purchase has a tighter fit!

Probably what I wrote above... your plug is 5x2.5 while socket is 5x2.1... get a 5x2.5 socket (or simply a small adapter)

[6ix5ive]

... your plug is 5x2.5 while socket is 5x2.1

I suspect as much too, duly noted!