TX mixer

The problem with the TX seems to be solved. It was not oscillating after all.

My tx mixer consists of a NE612 mixer. This device mixes the 10.7 MHz signal from the modulator with the 134 MHz signal from the PLL.
This signal is amplified by 2 MAR 6 amplifiers. Then the signal is boosted to 30 mWatt by a BFY90. Band filters are placed between the stages.

While peaking the band filters I found that the output jumps to maximum rapidly. I thought it was oscillation. Sometimes when power is turned off and on again the output is lower than the previous value. This is pretty weird.

The problem was in the second mar6 amplifier. It seems to behave like this when output is almost at maximum. So it looks like it was overloaded . I was able solve it by decreasing the resistor from the MAR6 to the 12V.