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How to properly bridge 2 mono jacks using a 1uf capacitor and connect to rheostat? Answered

Hello everyone, I am struggling on the proper way connect a few parts in my power source. At the moment I am about to wire my rheostat to a mono jack. From there I need to wire a 1uf capacitor to a 2nd mono jack. I do not understand where to connect each wire. I know how to wire the rheostat to the first jack but from there I do not know how to properly bridge the 2 jacks with the capacitor. I know I need to connect both jacks but how do I wire this? Do I connect the capacitor between both "ground" leads on the jacks? Does this also constitute  connecting both jacks in general? Also, the 2nd jack will be connected to the rest of the negative circuit in the source. I really hope I explained this well enough. I am new to electronics and I am still not that familiar with terminology so please bare with me. I would appreciate any help offered. Thank you in advance!


First, your supply MUST have a fuse in the secondary, 18V side of the supply - a 2A fuse on the primary will allow up to 220W on the secondary side, which will destroy your rectifier.

Using a rheostat to control a power supply like that is a very, very bad idea. From the ratings you suggest, your rheostat will dissipate a huge amount of power, and your output voltage will vary wildly under load. Use a proper LM317 or L200 regulator.

The jack question: what kind of jacks are they ? RCA ? If they're RCA, you only need ONE jack to connect. The centre goes to supply +, the outer to supply -

Thank you for your input steveastrouk. I do need the output voltage to range from 1-12v. Will what you suggest provide the varied voltage? The jacks I am using are mono phone jacks. I think they are 1/8. They have the tip for the mono plug to rest on and than 2 connection spots. I can only assume one is ground and one isnt? Thank you!

The 317 can't control below about 1.5 volts, but will be fine for 1.5...12V. The tip of your jack should be connected to the supply, the body to the ground.

What are you trying to make and what if any schematic are you using?

Mpilchfamily, I am trying to build a DC power supply. I am using an 18v transformer and want to reach up to 12v max. I am also using a 2amp fuse, 4amp bridge rectifier, 3300uf cap, 100uf cap, 1uf cap, 35 ohm rheostat, on/off switch, 2 mono jack sockets. I drew out the schematics for you that I am using. Its the best I could do and I hope you can understand it. I'm still learning the proper way to draw these out. Thank you for taking your time to help me out!


As steve says, your rheostat will get ugly hot; look up the circuit for an lm317 variable voltage regulator in place of the rheostat.