New Allen Telescope Array Development

PURPOSE: We bought several RF switches so we can remotely select antenna pol outputs and direct them into a SNAP board one at a time. This will avoid a lot of manual SMA connector inserting/removal, as well as allow us to do a lot of testing remotely.

June 05, 2018 - received the mini circuits attenuator and 8 port RF switch. Two of each.

Note: the software to control these things is at https://github.com/jrseti/ATARFSwitchUtils

This is how I have it hooked up as of June 07, 2018 - JR

Note: That is a quarter coin in the center for size reference.

Plugged into VM server ngs-work1 (sonata@10.1.49.174, polaris)

1. Attenuator RUDAT-6000-30: https://www.minicircuits.com/WebStore/dashboard.html?model=RUDAT-6000-30
2. RF Switch USB-1SP8T-63H: https://www.minicircuits.com/WebStore/dashboard.html?model=USB-1SP8T-63H

Created 2 programs, rfswitch and atten to control these units over USB. See https://github.com/jrseti/ATARFSwitchUtils for a full explanation and the source code.

root@nsg-headnode:~# qm monitor 101
qm> info usbhost
  Bus 3, Addr 5, Port 14.1, Speed 1.5 Mb/s
    Class 00: USB device 0557:2419
  Bus 3, Addr 8, Port 12.4.4, Speed 12 Mb/s
    Class 00: USB device 20ce:0023, Mini-Circuits
  Bus 3, Addr 7, Port 12.4.2, Speed 12 Mb/s
    Class 00: USB device 20ce:0022, Mini-Circuits
  Bus 3, Addr 10, Port 12.4.1.3, Speed 12 Mb/s
    Class 00: USB device 20ce:0022, Mini-Circuits
  Bus 3, Addr 9, Port 12.4.1.1, Speed 12 Mb/s
    Class 00: USB device 20ce:0023, Mini-Circuits
    

Note the port numbers (like Port 12.4.4)

In Proxmox, assign the usb ports as shown:

The head node needs to be rebooted to make the USB changes work.

Note that the USB ports need to be assigned by port, not by device vendor and product ID. If you set up the ports assigned to vendor and product ID, you can only have one RF switch on the USB bus recognized at one time. So, use the port numbers like 12.4.1.3.

The RF switch and attenuator units are installed at the top of the FXA Rack just to the right of the RFCB rack: