Description

Wideband Signal Generator (ADF4351, 35 - 4400 MHz)

(The second photo is a prototype and is different from the data.)

This is a wideband signal generator designed by DD7LP, who lives in Germany.

Please refer to the data required for production here.

https://github.com/dd7lp/AD4351-PLL-Syntesizer-35-4400Mhz-DD7LP-2

(The copyright of the signal generator described below belongs to DD7LP. Any use other than personal production, such as commercial use, is not permitted.)

This article shows how to make a signal generator using this printed circuit board.

https://me-yoh.com/making_wideband_signal-generator-2

Main parts

-ADF4351 evaluation board: 5th photo

-Arduino NANO

-TFT LCD 128 X 160 dot, ST7735

-Rotary Encoder

-RF Amplifier board : 6th photo

-10MHz TCXO

-74HC132

How to operate the DD7LP frequency synthesizer

When you turn on the signal generator, it starts operating at the preset frequency of 144.9 MHz.

The signal level on the initial screen is -4 dBm and the frequency step is 10 kHz.

(See the screen in the 7th photo.)

1 When the ADF4351 locks to the specified frequency, "LOCK" is displayed.

2 If the oscillator is internal, "REF.int" is displayed. When an external reference signal is detected, the display will change to "REF.ext."

3 Output level. Pressing the switch of the step switching encoder switches between "-4", "-1", "+2", and "+5".

4 Number of steps for frequency increase/decrease. Turning the step switching encoder switches between 10 kHz, 100 kHz, 1 MHz, 10 MHz, 100 MHz, and 1 kHz. The minimum step is 1 kHz due to the IC limit.

5 Output frequency. Turning the frequency encoder increases or decreases the frequency by the value set by the number of steps.

Pressing the switch of the frequency encoder also switches to a preset frequency.

The preset frequencies start at 144.9 MHz, then switch between 432.9 MHz, 1296.9 MHz, 2320.9 MHz, 3400.9 MHz, 2880.4 MHz, 3456.3 MHz, 3435.5 MHz, 4277.1 MHz, 35.0 MHz, and 50.1 MHz.