Broadband RF Preamplifier Active Antenna Booster
Here is the schematic: RF Preamplifier Circuit
Here are the connection directions: Connecting Your RF Amplifier
The optional connection method was 7 turns of 22 AWG wire wound around the center of one of ferrite rods. Here are alternate connection directions: Using Optional Ferrite RF Output Rod
I designed this RF Broadband Preamplifier mainly for Crystal ( Xtal ) Radio sets.
It is not as pretty as the $100.00+ Broadband RF Preamp units but with the addition of the optional ferrite antenna output coil it will work using the same coupling method as some of the more expensive RF Preamps .
These are made by me with my own circuit design it has not been copied form another design and I have never seen one like it anywhere for RF .
A broadband preamp will have a little more noise than a narrow RF band preamplifier. However unlike the over $100.00 Broadband RF Preamplifiers (Active Antenna Boosters) for a few dollars you can add a tuned input known as a pre tuner and make it narrow band RF preamp as the input is assessable and not molded in a plastic case.
Frequency response 100Khz to 25-30Mhz.
The battery only draws about 2ma current. So a 9 Volt battery will last a very long time.
If your location or space limitation prevents you from having a 100ft or longer antenna then this Broadband RF Preamp Active Antenna Booster will allow you to use a 15ft or so antenna.
If you live in a rural area and need a long antenna to receive AM stations on your crystal or AM radio then this RF preamplifier is for you. I live about 20 miles from the nearest AM station and even with a 15ft antenna I can barley get one station on my crystal radio set. With this RF preamp and a 15ft antenna I get three stations on my crystal ( Xtal ) radio set.
Many people put audio amplifiers on there crystal ( Xtal ) radio sets. However it takes about .1 volt for the diode to conduct so stations not able to produce at least .1 volt from antenna do not pass into the audio amplifier so hundreds of times audio amplification times nothing equals nothing.
Comes with directions to connect with just about any crystal ( Xtal ) radio set or receiver with 50 to 300 Ohm inputs or to any receiver without these inputs with the optional ferrite output coil.
You need a 9 volt battery and wire for the antenna and ground.
If you have any questions email me before you purchase the RF preamp.