- #1
Ravaner
- 134
- 3
Hello. I have devolopped a line amplifier with 3 x MAR-6 MMIC. Normal daisy chain is : antenna followed by a LNA which is followed by my line-amp. If nothing is connected at the input ofLNA, all 3 Mar-6 have normal operating voltage ie 3.5 V and resulting noise is very low (seen with a 100 MHz scope). Since horn antenna is connected, and even if just a 1/4 wavelenth wire (51 mm) is connected at the input of LNA, the 3rd Mar-6 has is DC voltage drop to 1.8 V ! As it works far from 1 dB compression point, how this can be explained ?