battery14v
Newbie level 5
Hi , Guys
I have UHF FM Transmitter with power about 5W
I want it to send video signal through AM the carrier frequency
here the important section of schematic :
I tried to inject signal in Q407 emitter ( i think this make low level AM ) after remove R408 the picture shows up in my TV with lot of noise and no luck with range .
Then I tried same thing with another VHF Transmitter ( thinks modifying in low frequency easier and lower the interference is it right ) and here is the VHF one :
the point i inject the signal is Q3 emiter
The picture show up in tv with good range about 300M ?? with dipole antenna both TX RX .
this is my way to inject signal :
is this Method below better ??? ( it is done in RF power amp stage Not like i'm doing IN per amp or buffer stage ?? )
the Transmitter's I have is have PPL and VCO to control and stabilize the carrier frequency
thanks a lot
I have UHF FM Transmitter with power about 5W
I want it to send video signal through AM the carrier frequency
here the important section of schematic :
I tried to inject signal in Q407 emitter ( i think this make low level AM ) after remove R408 the picture shows up in my TV with lot of noise and no luck with range .
Then I tried same thing with another VHF Transmitter ( thinks modifying in low frequency easier and lower the interference is it right ) and here is the VHF one :
the point i inject the signal is Q3 emiter
The picture show up in tv with good range about 300M ?? with dipole antenna both TX RX .
this is my way to inject signal :
is this Method below better ??? ( it is done in RF power amp stage Not like i'm doing IN per amp or buffer stage ?? )
the Transmitter's I have is have PPL and VCO to control and stabilize the carrier frequency
thanks a lot