TTY Loop Control Panel Part 2
In this video I build and test a current loop control panel for the teletype equipment.
I have been using the HAL ST-6 terminal unit to supply loop current to my teletype setup. This worked ok but there were two issues with this. First, there are times when I want to use other terminal units that may not have a built-in loop supply. Second, the ST-6 was never meant to power as many devices as I have on the loop. So the current has dropped from 60mA (nominal) to less than 50mA at times. So I decided to use a Navy external 1,000 mA supply model PP-3495A/UG. To do this, I had to develop a current limiting circuit. Part 2, I build and test the control panel.