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essentially I'm trying to make a very basic circuit where a 3.7 volt battery is wired to a liquid crystal display, (or LCD), and the brightness of said display is controlled by a pentiometer to variably resist voltage headed to the LCD display. In theory, twisting the dial should resist voltage going from the battery to the LCD thus darkening or lightening the screen. Unfortunately as of right now the display is either completely dark with the battery in or clear if the battery is out and the pentiometer does nothing one way or another. I have no idea how to fix this so any help would be great. Pictures of the circuit are below. Keep in mind in the pictures that the solder to the two pins on the pentiometer are not actually touching though that is how it appears. Thanks.

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  • \$\begingroup\$ It is impossible to say anything because you give no info about the display (backlight voltage, backlight current, part number, link to datasheet) or the potentiometer ( resistance, max power, part number, datasheet link). \$\endgroup\$ – Justme Aug 12 at 4:38
  • \$\begingroup\$ your soldering technique is very sloppy ... you have too much solder on the connections ... you are also missing insulation on the connections ... there is a very good chance that the battery or some other part of the circuit may become shorted \$\endgroup\$ – jsotola Aug 12 at 5:05
  • \$\begingroup\$ The display is a transmissive liquid crystal display with a driving voltage of 3-5V and the potentiometer is a standard 10K ohm linear potentiometer with 0.1" spacing. As far as the soldering, it is definitely less than perfect but it does still carry the voltage all the way through the circuit so my problem most likely does not lie in the solder joints but somewhere in the setup itself. \$\endgroup\$ – ElonMunk Aug 13 at 18:05

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