Showing posts from July 8, 2016

The struggle to make the ADF4351 10MHz reference signal.

The ADF4351 PLL needs a  full TTL level  at 50OHm in the 10MHz reference.
The internal TCXO delivers 5V pk  at the ADF reference port. Then the resulting signal at 1296 / 1152 MHz is a clean small carrier about 60dB S/N  at the SDR RTL stick Using  400mV tt  clean sinus signal from the amplified GPSDO ( 40mV pk) gave a broad raspy tone at the output port of the ADF I tried a MMIC demo ampl. with the MAR6  and INA10386 DC to 2GHz broadband amps   got a clean 40mV pk 10MHz  at the input of the INA  measuring 5V DC supply ,  2V bias at the output pin and  0.2V bias at the input pin of the INA10386,  normal levels. 40mV tt at the input resulting in 0V out.. coupling C 10nF  L 10uH Why this MMIC do not work for 10MHz ? i do not know yet maybe  my  10MHz  driving issue can be solved by a simple opamp or an other discrete part amplifier like the one below optimised in Multisim I  have to be sure of the solution before I start to trial and error soldering again It can not be that difficult t…