Tag: serial

SDR Panadpter, logger, and skimmer

With a TenTec Eagle transceiver, Managed by N4PY software.

n4py-diagram

http://www.n4py.com/

N4PY acts as router, distributing CAT commands to other applications.

The applications are connected using virtual serial port bridge pairs. For each of the applications, N4PY emulates a K3 transceiver on one side of the bridge.

  • Panadapter: NAP3
  • Logger: N1MM
  • CW Skimmer

The CW keyer is a K1EL Winkeyer USB controlled solely by the N1MM logger.

The routing of IQ signals from LP-PAN2 SDR is done through a MOTU 828 mk3 interface, simply to be able to split the signal so that both NAP3 and CW Skimmer can use it.

CW Skimmer gets the IQ signal directly from the MOTU. NAP3 doesn’t not recognize multiple ports on soundcards. So one end of the split from the MOTU is sent through another audio interface (Focusrite 2I2). NAP3 uses the 2I2 as an input device.

LP-PAN frequency adjustments

Notes on configuration for correct zero-beating.

When setting the Eagle BW or PBT, the IF will shift in frequency, so the numbers below assume a centered PBT and a BW of 700.

The sidetone pitch is 523 Hz.

Settings may also depend on which roofing filters are installed in the Eagle.

NAP3 settings

Set the global offset to -8200. Leave everything else at 0.

CW Skimmer settings
  • CW pitch: 523
  • Audio IF: -7520
  • Sample rate: 96 kHz
  • Hardware: SoftRock-IF

This post is about ham radio.

Virtual serial ports in Windows

Using Virtual Serial Port Manager

Setting a local bridge to connect the 2 virtual serial ports allows a Max patch to communicate with a radio on a real serial port and pass through the data to a virtual serial port that can be used by another program, such as a logger. The patch looks like this:

Screen Shot 2016-04-07 at 10.09.47 PM

 

Its looks like a feedback loop but its not. In this case the bridge is: com1 <-> com2. Com1 is port a in the above patch. Data sent to com1 can be read from com2 and vice versa.

 

Remote radio – server

How to run the server side (base station) of the remote shortwave radio system.

(Under construction) The patches have not been uploaded to github yet.

Assuming that the radio and antenna system are operating. We are using an internet connected MacBook Pro running OSx 10.9.5, with a MOTU 828 MK3 audio interface.

VPN

Install and set up LogMein Hamachi. It is free, for a limited number of computers.  Set up a Hamachi server on both the server and client. It should look something like this:

 

VOIP

We are using Soundjack VOIP. It is also free. Use the following parameters on the server side.

Local Settings:
  • mic: audio interface channel that is connected to radio audio output
  • headphone: doesn’t matter
  • volume: 0
  • audio block samples: 512
  • channels: 2
  • network packet samples 512
  • quality: high
  • userlist: manual

Screen Shot 2016-04-05 at 12.38.03 AM

User list:

UDP/IP: enter hamachi IP of client.

When Soundjack is set up on the client. Press the green start button on the right side of the user list window on the server.

If all goes well, you should hear the radio on the client. Note: The input meter under local settings should be registering audio from your radio. If not, there is a problem with the audio interface.

Max Server

The Max/MSP server exchanges CAT commands via the server serial port to the radio. The command data is exchanged with a Max patch on the client using OSC (over UDP).

Screen Shot 2016-04-05 at 12.46.02 AM

patch:

eagle-cat8.maxpat

instructions:
  • select the radio serial port from the menu (for example: usbmodem 14531)
  • initialize port settings
  • set toggle to poll the serial port

At this point you should be able to try the example commands, for instance to get the version or set frequency. If the commands are not working, it indicates a problem with the serial connection to the radio.

Next, check the IP address of the udpsend object. It should be the hamachi IP of the client.

 

Remote controlled shortwave radio system

Under construction…

The first in a series describing a system for internet remote control of a shortwave radio station. Its not something new. There are commercial products that provide remote operation of amateur radio transceivers. The purpose of this project is to make it possible to use shortwave radio sounds in musical performance, without the need of an antenna system.

Features:

  • Max/MSP for USB serial control of radio, OSC remote interface, user interface, Midi device handling, and an SQLITE database of preset frequencies.
  • Low latency, good quality audio using Soundjack by Alex Carot.
  • Hardware control of radio using Midi controllers (CDJ-101 and Launchpad)
  • Bi-directional OSC and VOIP using Logmein Hamachi VPN
  • Additional hardware control of AC power and antenna selection using Arduino and a WeMo switch.
  • TouchOSC Ipad audio mixer control using MOTU Cuemix
  • TeamViewer remote desktop software for logging into to base station compuer
  • Optional radio user interface control with Ipod TouchOSC, Griffin Powermate dial, and Korg Nano-kontrol.
  • Optional VOIP backup using Mumble.

System diagram

base station:

remote-radio-sys1

remote control:

remote-radio-sys2