EMRFD Message Archive 12471

Message Date From Subject
12471 2016-03-04 18:34:58 Ken Chase Supply decouple resistor

Hi All


Looking through EMRFD, some of the small signal amp have a resistor in the supply line to toroid then collector. I think this is called decoupling resistor.


What is the purpose of this resistor?


Example in EMRFD Page 2.20 Fig 2.57 43 ohm on the 12 volt line.





12472 2016-03-04 19:32:26 Dana Myers Re: Supply decouple resistor
12473 2016-03-04 20:16:18 farhanbox@gmail.c... Re: Supply decouple resistor

if there is a resistor in series with an inductor as a load to the collector, it is a bias to limit the voltage on the collector. this is often used in mmics where we do not have control over the internal biasing. i guess there was an app note on some mmic vendor's site.

- f

12474 2016-03-04 20:20:27 Dana Myers Re: Supply decouple resistor
12475 2016-03-04 21:49:41 kerrypwr Re: Supply decouple resistor
The resistor provides de-coupling and also affects the bias; see the note relating to Fig 2.15 and Chapter 2.7.

Kerry VK2TIL.