Differential current detector in cable television trunk amplifie

Details Differential current detector in cable television trunk amplifie Differential current detector in cable television trunk amplifie

1980-10-01

1983-10-25

Orsino, Jr., Joseph A.

Facsimile and static presentation processing

Static presentation processing

Attribute control

361 93, 455 9, H04N 710

Patent

active

044122454

ABSTRACT:
A voltage comparator compares the DC current in active elements of a trunk amplifier with a variable reference voltage for detecting when to switch to a bypass mode. Its output is normally low for passing a current through it, an LED, and relay coils when the amplifier operates satisfactorily. Circuitry for establishing an allowable amount of decrease in DC current in a current sensing resistor R5, prior to switching the comparator for de-energizing the relay coils, comprises a first transistor Q4 that continuously conducts collector current through a load resistor, a second transistor Q2 that is only responsive to a low output voltage of the comparator for passing a prescribed current through the load resistor for decreasing the first transistor Q4 collector voltage a prescribed amount, and circuitry including voltage dividers for coupling a greater percentage of the change in Q4 collector voltage to the positive input of the comparator than to the negative input thereof which also senses the level of the DC current.

REFERENCES:
patent: 3737774 (1973-06-01), Verhagen
patent: 3973185 (1976-08-01), Beak et al.
patent: 4241373 (1980-12-01), Mara et al.
patent: 4278930 (1981-07-01), Rogers
patent: 4331996 (1982-05-01), Matsko et al.

Affiliated with

Also associated with

Rating

Differential current detector in cable television trunk amplifie does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Differential current detector in cable television trunk amplifie, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Differential current detector in cable television trunk amplifie will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-715180