Skip to content

  • Projects
  • Groups
  • Snippets
  • Help
    • Loading...
  • Sign in
R
RF Multiplexer 8ch 1GHz
  • Project
    • Project
    • Details
    • Activity
    • Cycle Analytics
  • Repository
    • Repository
    • Files
    • Commits
    • Branches
    • Tags
    • Contributors
    • Graph
    • Compare
    • Charts
  • Issues 3
    • Issues 3
    • List
    • Board
    • Labels
    • Milestones
  • Merge Requests 0
    • Merge Requests 0
  • Wiki
    • Wiki
  • image/svg+xml
    Discourse
    • Discourse
  • Members
    • Members
  • Collapse sidebar
  • Activity
  • Graph
  • Charts
  • Create a new issue
  • Commits
  • Issue Boards
  • Projects
  • RF Multiplexer 8ch 1GHz
  • Wiki
  • Home

Home

Last edited by Anders Wallin Nov 10, 2020
Page history

RF Multiplexer 8ch 1GHz

Project Description

This is a PCB-design + Arduino firmware for an Ethernet-controlled 1:8 RF-multiplexer (SP8T). It allows selecting as output one of eight input-channels, as commonly used e.g. in timing-laboratories when one wants to measure many RF-sources (clock outputs like 1PPS or 10MHz) with a single instrument (frequency or time-interval counter). The unselected channels are terminated at 50 Ohms. The design is for two independent MUX-boards to fit in a 1U 19” rack enclosure together with an Arduino MKR ZERO microcontroller with Ethernet interface. The firmware allows for simple control over http with a browser or e.g. the python requests library.


Main Features

  • PDF design files 2018.02: Schematic and PCB
  • SP8T: 8 inputs, 1 output. Nominally 50 Ohm characteristic impedance. BNC or SMA connectors.
  • Bandwidth >1 GHz
  • TE HF3 signal relay with lifetime of 1e7 operations (19 years at a rate of one operation per minute)
  • older design: Arduino Duo + Ethernet Shield controller
  • current design: Arduino MKR Zero + Ethernet Shield controller
  • 10/100 Mbit/s Ethernet, simple control over HTTP (see vide of initial tests https://youtu.be/fustqTdP5m0)

Components and datasheets

  • TE HF3 Relay
  • MCP23S17 16-Bit SPI I/O Expander with Serial Interface
  • ULN2803A Darlington Transistor Array

Similar projects

  • Open:
  • TAPR TASS DC-150 MHz
  • k5lxp 6x2 Coaxial Remote Antenna Switch
  • Closed/Commercial:
  • Pulse Research Labs PRL-8108 DC to 1.5 GHz SP8T multiplexer with 3-bit control. $ 1,707.75.
  • Mini-Circuits RC-2SP6T-A12 DC to 12 GHz 2SP6T multiplexer with USB and Ethernet control. SMA connectors. Around $2395.

Contacts

Design and general questions

  • Anders Wallin (anders.e.e.wallin "at" gmail.com)

Commerical producers

  • Aivon LTD

Status

Date Event
2018-02-15 First PCB revision http://www.anderswallin.net/2018/02/rf-multiplexer-first-try/
2018-04-25 Second PCB revision http://www.anderswallin.net/2018/04/rf-multiplexer-version-2/
2018-06-12 OHWR-page rf-mux-8ch created
2018-06-17 initial commit of design to repository: mux-board, due2sata board, enclosure, mux-sw
2018-08 simplified design with no on-board voltage regulators and 10-pin IDC-cable for control.
2018-11-24 design update for kicad5 symbols and footprints
2019-09-07 Arduino MKR Zero carrier board files on wiki
2019-11-27 Revised carrier for Arduino MKRZero, with front-panel pushbuttons
2020-03 40-channel 3-unit 1PPS measurement system in operational use at VTT MIKES
2020-09 Revised mux-PCB with SMA-connectors as option
2020-11 Revise schematic to note that MCP23S17 io-expander address bits A0, A1, A2 must be externally driven (not left floating)

Revised front-panel with pushbuttons B1 and B2. From S/N 4 onwards (2019-11).:

20191128_130703

Internal view of S/N 4. Rightmost is the MKR ZERO Ethernet shield, followed by the MKR ZERO, and the carrier-board which takes +5VDC input and has two 10-pin IDC ribbon-cables to the MUX boards.

20191128_141949

3x1U MUX-units for a 40-channel 1PPS measurement system. Installed at the VTT MIKES UTC-laboratory in March 2020. The boards are connected (cables not shown) in a tree configuration. One 8-channel MUX-board is used as the root node, where each channel connects to a leaf-MUX. This provides a capacity of 8x8= 64 channels, if seven leaf-MUXs are used. Here we only have 6 MUX-boards in 3U, so 5x8= 40 channels. This system is in continuous 24/7 use with all channels measured every 600s (10 minutes).

RF_MUX_40ch-scaled

Transmission bandwidth test on S/N 4. Note Y-scale is 3 dB/DIV. Bandwidth is >1 GHz.

2019-11-28_rfmux_transmission-1

Older prototype with Arduino Due:


Clone repository
  • Documents
  • Home
  • News
  • Documents
    • 2018.02 design snapshot
    • 2018.08 rf_mux design snapshot
    • 2018.11 arduino mkr zero carrier board
    • 2018.11 design
    • Images
More Pages

New Wiki Page

Tip: You can specify the full path for the new file. We will automatically create any missing directories.