* Unique and simple FM booster circuit that can be built at your home using a couple of components within minutes!

* Outdoor mast mounted high gain low noise amplifier and Indoor signal gain control cum PSU

* High quality stereo reception

* Enables FM DX. Now receive your favorite FM stations from greater distances, that too in stereo!

* Low cost, no complexity, extremely simple circuit design.

* Indoor gain control offers large dynamic range even over strong local signals, which means you can connect low-end portables also to the booster without worrying about front-end overloading.

* Just build it and connect to your high-end FM tuner/Hi-Fi music systems/Car radio/tabletop-portables and enjoy outstanding quality reception.

Video link:  https://www.youtube.com/watch?v=O_SBGKM9veU

      I've started working on an FM signal booster since there have been many interests noticed recently for a working VHF FM booster which can amplify weak or distant signals(or even those locals which appears hesitant to enter your home/building and mark a presence on your tuner/radio).

I've worked on few designs -both indoor and outdoor type amplifiers, and this one seems to be working great and promotable considering it's simplicity and easy to make, offering great reception.

BoostMan followed good old terrestrial analog Television booster architecture having a dipole antenna attached at top-mast to the booster amplifier and an indoor PSU cum gain control unit. 75ohms feed cable like RG59/RG6 is used as feeder cable.

Fig.1 Schematic of FM booster

Block Diagram

Antenna

Performance

WIth a homemade folded dipole antenna, I could receive 30+ local and distant FM radio signals across the state and nearby states, ie, hundreds of kms away. DXing is very nice to witness, especially when the signal comes in and engage the stereo decoder for a short time and then fade away or just be there jumping in/out. It's a pleasure to watch it on the tuner operation indicators. Signal presence, Signal strength, Stereo, VU -all will dance during a DX window!

Pictures of raw and assembled PCB

PCB Layout

Components List

R1 - 27K 1/4w, metal film resistor
R2 - 330E 1/2w, metal film resistor
R3 - 1.5K 1/4w, metal film resistor
VR1 - B47K, linear potentiometer with knob and mounting nut
Q1 - 2SC3355/2SC2570 Genuine NEC/RENESAS/UTC Transistor
C1/C2 - 47pF ceramic disc
C3/C4/C5 - 0.001uF/102P ceramic disc
X1 - 0-12V Step down transformer 100mA. A 500mA output transformer can be used instead.
B1 - 250mA fuse
D1 - 1N4007 rectifier
L1 - 20 turns of 22SWG[0.7mm] enamelled copper wire closely wound on a 5mm former, air core
BP87108 or GFMB3 wideband BPF [only for Version 1 circuit]
RG59/RG6 75ohm coax -length as per required, F-type/BNC coax connector

Downloads

Printable PCB layout of Version 2 circuit can be downloaded here