John's Arcade Forum - Classic Arcade and Pinball Collecting and Restoring Discussion Forum - RETRO MAME - Nintendo Vs Forum
October 31, 2024, 06:45:45 pm *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Welcome to the John's Arcade Forum. Glad you made it! Smiley
 
   Home   Help Search Calendar Login Register  
Pages: [1]
  Print  
Author Topic: Help with Potentiometer  (Read 1377 times)
0 Members and 1 Guest are viewing this topic.
jasonsmith
Full Member
***
Offline Offline

Posts: 216


View Profile
« on: April 29, 2014, 10:43:59 pm »

I want to increase the resistance value of this potentiometer. Or actually change it's range.



Right now it is zero to 50k ohm, I want it to mod it to be around 25 to 75ohms.

I want to add around 25k to the start of it's variability.

There's 3 legs on the thing, where should I put the 25k resistor? I'm thinking onto the leg after R359??
« Last Edit: April 29, 2014, 10:47:48 pm by jasonsmith » Logged
jasonsmith
Full Member
***
Offline Offline

Posts: 216


View Profile
« Reply #1 on: April 29, 2014, 11:37:00 pm »

Took it out and played with it a bit and I was correct. If I add a 25k resistor to the non ground leg it starts the pot at 25k and goes to 75k vs 0 to 50k.

I heard of a mod similar to this for a Centipede. I'm thinking the HOR Hold circuit just wasn't built to take the age of these components. As you know in my other thread I'm suffering from some stretch or curl on the left side of the screen. Adjusting the hold starts to take it away but the hold maxes out. If I dial it back from max it's pretty quick to lose it's hold so that telling me the first 50% of the range is doing nothing.

I should merge these two posts into the other thread...
Logged
Pages: [1]
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Install Simple Machines Forum Valid XHTML 1.0! Valid CSS!