S smorteza New Member Mar 12, 2004 #1 Hi. What should I do to hold four telephone_line with one hold_circut that none of them can hear speaking of other lines. Thanks.
Hi. What should I do to hold four telephone_line with one hold_circut that none of them can hear speaking of other lines. Thanks.
R Russlk New Member Mar 12, 2004 #2 To hold the line "off hook" you just have to put a current load on it. Use an opto isolator with transistor output and resistor load on each line. Do you have a power supply for the LEDs?
To hold the line "off hook" you just have to put a current load on it. Use an opto isolator with transistor output and resistor load on each line. Do you have a power supply for the LEDs?
crazymonkey New Member Mar 13, 2004 #3 Check out this site https://www.aaroncake.net/circuits/phonhold.htm. I don't know if it will work, you'll prob have to build 4 as well.
Check out this site https://www.aaroncake.net/circuits/phonhold.htm. I don't know if it will work, you'll prob have to build 4 as well.
L ljcox Well-Known Member Mar 13, 2004 #4 You can hold the line by connecting a 470 Ohm 2 Watt resistor across the line. Len