Tracking Generator 10-1500MHz


Tracking Generator designed to use with HP Spectrum Analysers.
Version 09.2012
Update: 08.2013
Update: 12.2016

Improved purity of Output Signal .
Improved Level Linearity (ALC Circuit

- Output Level: -13...+5dBm (10...1550MHz)
- Leveled Output: 0dBm (1mW)
- Output flatness: max. +/-2dB with LTC5505-1 (was installed after). Also without ALC, the results are satisfactory.
- I use only one Mixer: Double Balanced PAM42, the box with Single Balanced Mixer is used only for 1,7GHz Stepped Low Pass Filter.
- Also a 2 diodes Balanced Mixer (S53MV) working very nice for this project.

ALC Test, bypass loop (output of TG at input of SA), Span: 100MHz/divison, 10dB/division
Ripple is produced by SMA connectors and coaxial cable:
-ON ALC - 50cm of RG174 (Same measurement made few years ago)
-OFF ALC - 50cm of RG174
-ON ALC - 15cm of rigid coaxial

-OFF ALC - 15cm of rigid coaxial (minimum output level, ALC out of range)

Test example
Band Pass Filter NEC tested at 1300MHz
The Results:
-with ALC circuit
-without ALC circuit


Block Diagram
Mixer, Amplifier 2-3,55GHz, Output Amplifier: Schematic, PCB, Components Position
Pin Diode ALC, Low pass filter 2,8GHz: Schematic, PCB
VCO 2,05GHz: Schematic, PCB
(PLL not used, only VCO section)
ALC: Schematic, PCB (Sprint Layout 6)

Tracking Generator Photos
Mixer, 1,7GHz Low Pass Filter, ALC Circuit, LTC5505-1 Detector
VCO 2,05GHz, Low Pass Filter, PIN Attenuator
ALC Comparator
PIN Modulator

Other pdf files
AN150-3 Spectrum & Tracking Measurements
Tracking Generator DJ4GC VHF Com.
PAM-42 >Datasheet<, >Aplication Note<
BGM1012 Datasheet
ABA-52563 >Datasheet<, >Aplication Note<
HP8444 Service Manual

Tracking Generator HP8558 - Analog Circuits Cookbook II 1999

About Microwave Mixers
Mixer Balanced in SSB Transceiver for 1296MHz - HamRadio september 1974
Balanced Mixer for 2304MHz - HamRadio octomber 1975
Rat-Race Balanced Mixer for 1296MHz - HamRadio july 1977
How to use Double Balanced Mixers for 1296MHz - HamRadio july 1975





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