Active 2-way RX splitter board

The splitter is a very useful device. It can provide equal voltages, equal current, or equal power to matched or unmatched loads. This is active splitter version where you can switch ON high IP, low noise preamplifier and eliminate insert loss of the splitter. Gain can be set as you need by the Variable ATT at PCB. This HW is designed only for RX line. There are some more high current and voltage protections on all ports. Both impedances 50 or 75 Ohm can be selected by the jumper.

Main functions:

• Info:
  • Broadband: 0.1 MHz to 60 MHz
  • 2-WAY Splitter
  • Passive (4,5dB loss) or Active (up to 14 dB gain)
  • Bypass of Preamp by relays
  • Low loss, high gain, low noise, high IP3 preamplifier
  • Front-end protections- high voltage / current
  • 50/75 ohm impedance - easy jumper switch
• Electrostatic protection with glim lamps.
• High power protection.
• Quality SMA connectors.
• Available as
  • KIT : all parts + PCB
  • Assembled : ready to use

Parameters:

• Info:
  • Impedance 50 or 75 Ohm
  • NPN transistor 2SC5551A
  • Supply voltage 12 - 14 V
  • BIAS current 10 to 70 mA
  • Supply current up to 180 mA includes relays!
  • Gain: up to 14 dB
  • Low Noise Figure (NF) 1,2 dB (20 mA 50 MHz)
  • Low Noise Figure (NF) < 2 dB (60 mA 50 MHz)
  • REAL IP3 34 dBm
  • Input diode limiter about +17 dBm
  • Bypass of Preamp without supply voltage
  • Insert loss with preamp OFF: around 1,5 dB together with the splitter around 4,5 dB
  • Insert loss with preamp ON: from about 20 dB loss (ATT with too high set) to 14 dB GAIN
  • Isolation more than 20 dB, 160-40 m more than 30 dB
  • SWR on OUT (splitted) ports better than 1:1,1 on HF, resp. 1:1,19 on 6 m
  • SWR on IN port around 1:1,2 to 1:1,7 depends on gain of preamp (Optimal is 10dB)
  • Maximal RF current 100 mA
  • Maximal RF voltage around 65 V

Use:

• Antennas splitter
• RX signal divider

Versions:

• KIT or assembled

The measured values

Isolation and SWR at OUT

In to Out, Preamp OFF

In to Out, Preamp ~10 dB

In to Out, Preamp max Gain

Download

2-way splitter
Schematic and board pic	sch	brd
3D board		brd
		41
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