RX preamp BOX with 2N5109 OK2ZAW

This is very simply preamplifier BOX module with 2N5109 transistor based on W7IUV design. You can use it as high IP preamplifier for RX antennas (beverage, DHDL, flag etc). Gain is up to 18dB and there is also build in variable ATT. You can easy set the gain as high as you need! As well you can set right transistor bias with multi turn potentiometer. Two relays offer bypass switching if there is no power supply voltage. You can use external power supply connected to the box or the bias tee box for power over the coax.

Main functions:

• Info:
  • Broadband: 0.1 MHz to 30 MHz
  • Very high IP3
  • Gain up to 18 dB
  • High output power up to 26 dBm
  • Variable ATT for gain 0 to 18dB
  • Bypass relays
  • Front-end diode protections. On/Off by Jumpers
  • Power over coax with the Bias Tee BOX - LINK
• You can set transistor bias as you need by trimmer
• High quality relays with TWO contact parallel
• Connectors SO239 or F
• BOX size 100x100 mm

Parameters:

• Info:
  • Supply voltage 12 - 15 V
  • Power directly or over the coax - bias tee - voltage 12 - 15 V
  • Supply current up to 180 mA includes relays!
  • Gain: up to 18 dB
  • REAL IP3 37 dBm for 18 V / 90 mA more here
  • Version with F connector is THT, SO-239 version is SMD

Use:

• RX ANT preamp powered over the coax
• High IP RX preamplifier - RX antennas
• Buffer amplifier
• Driver amplifier

Versions:

• RX preamp box ASSEMBLED and tested
• F version = THT, SO239 version = SMD, KIT F and SO-239 ONLY THT
• PACK of RX preamp box and Bias Tee box ASSEMBLED and tested
• KIT of RX preamp box: PCB + box + rest parts (THT) with transistor and radiator
• PCB only (for THT version)

The measured values

Gain 50 kHz to 1 MHz

Gain 1 MHz to 70 MHz

Input SWR, S11

Example with Bias-tee DC BOX and RX preamp BOX:

Download

RX preamp BOX module with 2N5109
Schematic and board pic	sch	brd
We believe open source is a better way of doing things. View and download the Shield Schematic and PCB files. The hardware designs are released under the Attribution-NonCommercial 2.0 Generic