Black Cat Systems
Follow our tweets!

Home
Purchase
News
Mac OS X Software
Mac OS 9 Software
Windows Software
Ham Radio iPhone/iPad
Linux Software
Documentation
Support/FAQ
Update Policy
Lost Reg Code?

Radiation Detectors
USB Icom CI-V Interface
MIL-STD-188 Interface

General Interest Programs

  Atomic Mac/PC
  Audiocorder
  Audio Toolbox
  Black Cat Timer
  Diet Sleuth
  iUnit
  Graffikon
  Graph Paper Maker
  Health Tracker
  Image Resizer
  Knitting Wizard
  Label Wizard
  Prog Audio Gen
  Sound Byte
  Synth 76477

Amateur Radio Programs
  Audiocorder
  Black Cat CW Keyer
  Carrier Sleuth
  Cocoa 1090
  Cocoa RTL Server
  DGPS Decoding
  DX Toolbox
  Elmer
  eQSL Factory
  MatchMaker
  MININEC Pro
  Morse Mania
  MultiMode
  mySdrPlayback
  RF Toolbox
  SelCall
  Sonde
  Squid Transformer

iPhone/iPad Apps
  ALE
  Atoms To Go
  dB Calc
  Clik Trak
  DGPS Decoder
  Drill Calc
  DX Toolbox
  Elmer Extra
  Elmer General
  Elmer Tech
  Feld Hellschreiber
  Field Strength Calc
  Function Generator Pad
  GMDSS
  Godafoss
  HF Weather Fax
  iAttenuate
  iFunctionGenerator
  iGeiger
  iSoundex
  iSoundByte
  iSweep
  iUnit
  Morse Mania
  ACARS Pad
  Morse Pad
  NAVTEX Pad
  Packet Pad
  PSK31 Pad
  SSTV Pad
  Photon Calc
  Rad Map Tracker
  RF Link Calc
  SelCall Tone Gen
  Sound Byte
  Sound Byte Control
  Spectrum Pad
  SWBC Schedules
  Synth 76477
  Synth Motion
  Transmission Line Calc
  Weather Calc
  Wire Calc

iPhone/iPad Bundles
  RF Calculator Apps
  Ham Radio Decoder Apps
  Audio Utility Apps
  Shortwave Weather Apps
  Ham Radio Exam Study Apps
  Shortwave Decoder Apps

Android Apps
  ACARS
  Audio Function Generator
  
Audio Spectrum Analyzer
  
DGPS Decoder
  HF Weather Fax
  NAVTEX
  Rad Map Tracker
  SelCall Tone Gen
  Sound Byte Control
  SWBC Schedules
  Wire Calc

About Black Cat Systems
Geiger Counter
Site Map
Our software for Mac OSX
Privacy Policy
Press/Media
HFunderground
Apple /// Emulator

Macintosh Links
Shortwave Radio
Pirate Radio
Spy Numbers Stations
Science and Electronics
Ham Radio Software
Geiger Counters


   

Receiving and Transmitting Morse Code (CW) With Your Macintosh



Introduction

Using MultiMode, you can send and receive morse code with your Macintosh. After connecting your Mac to your radio (see our interfacing notes for details on this), fire up your copy of MultiMode and set it for CW (Morse Code) mode.

Next, tune in a station sending CW. When properly tuned in, the tuning display, which shows a spectrum of the received signal, should look something like this:

The peak, which is the received morse code signal, is centered on the red line.

The demodulation display looks like this:

The dots and dashes are plainly visible here. The CW filter in MultiMode is fairly sharp, so proper tuning is required. Many radios also have a tight CW filter, so you want to make sure the center frequency in MultiMode is set equal to that of your radio. Also make sure that the audio level going into the Mac is adequate, without over-driving. We find that having it reach about the midway point on peaks works well.

Next, you want to select the correct speed for the morse code being sent, in WPM (Word Per Minute). You don't need to be very accurate here, being off a few WPM will still produce good decodes. You can also click on the AUTO button to have MultiMode automatically determine and set the speed. This usually works quite well, although it can be fooled by noise.

Decoded morse code characters will now start to appear on your screen. MultiMode can copy machine-sent CW very well. Hand sent morse can be copied if the operator maintains a proper dot/dash ratio, and spacing and speed. Very poorly sent morse code is difficult enough for a human to copy, let alone a computer!

For transmitting morse code, your Mac produces audio, at the same frequency specified as the center frequency. If you feed this audio into your transceiver, and transmit in SSB mode, you will end up transmitting on a single RF frequency, essentially duplicating a CW transmission.


Return to MultiMode

Return to Black Cat Systems


info@blackcatsystems.com
Chris Smolinski