Bi-Directional Amplifier Pictures

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Overview of the amplifier.  The entire board is mounted in a waterproof California Amplifier low noise pre-amplifier case.  The only reason for the two individual circuit boards is because I ran out of board material.  Ideally, it would all be one piece.  The N jack on the right side is RF input, and the F jack is the control line input.  RF output is on the left through a N plug.


Closer view, reversed.  The big silver thing is a Toko 2.45 GHz bandpass filter (4DFB-2450T-10) for the receive pre-amplifier.  The 7806 voltage regulator is mounted in the upper-left.


Top view.  RF output is on the right.  The RF2126 power amplifier is on the top, the HFA3424 receive pre-amplifier is in the middle.


Top view, left side.  You can see the control line input to the 2N2222A and RF1K49093 MOSFET.  The red coil in the yellow case is where the DC input power is taken from the feed line.  The DC input can be from 8 to 20 volts and is regulated by the 7806.


Close up view of the RF input, control input, DC power tap, and the RF1K49093 MOSFET.  The round orange thing is a tantalum capacitor.  Don't be retarded and let your soldering iron touch the plastic case on the inductors.


Close up of the HFA3424 receive pre-amplifier.  This little IC rocks.  It requires little in support components and has good overall performance.  You can also see the RF2126, which is really cool 'cuz it was free.


RF output PIN switch and 7806 mounting.  Be sure to mount the 7806 on something to act as heatsink material, and also remember it when you lay out your board design, or it will end up stuck in a corner somewhere.  :)


The (first) first prototype, complete with the rad microwave design skills.


DC power insertion back at the Symphony.  Apply power through an inductor that consists of about 28 mm of wire wrapped around a 6 mm air core.  It will need to handle a DC current of around 500 mA.  You can also see where I removed the low pass filter on the Symphony because it's no longer needed.  Replace it with a 0 Ohm SMT resistor.


The cool label.

New Style Amplifier Pictures


Picture of the new style amplifier.  Radio port is on the top left, antenna port is on the right.  The loose, dangling wires are from my experiments, don't construct your amplifier that way.  I also screwed up the antenna switch PC board pattern, hence the lame coax jumper.


Upside down view.


Close up picture of the RF detector circuit.  RF input would be on the left.  Also shown is the 5 volt regulator and part of the transistor/MOSFET circuit.