The PMRC Digital Education Net

PMRC repeater: 147.030 PL 91

A voice and data net to discuss digital modes

Every Tuesday evening at 1900 (7:00 PM)

Every once in a while we try a  "retro"  DEN  using the first digital mode: CW.  Actually, we will use  MCW  (modulated CW audio tones fed into an FM voice transmitter).  This is the same technique used by all FM repeaters to identify themselves in Morse.  The transmission is pure FM with a carrier, so the signal RF power does not go  ON/OFF  like "normal" CW.   The modulation is Morse, keyed at some audio pitch.  So an ordinary FM radio can detect and produce the keyed audio tones of the Morse signal.  Therefore, no BFO is  needed  (a beat-frequency oscillator is needed for SSB, RTTY, and true CW transmissions).

REMEMBER:  your radio must be in FM mode, not in CW !

There have been some questions as to how to set up the CONFIG Settings in FLDIGI  for   MCW.   Ask before the net begins... maybe call me or Ron NY3J  (co net control)  at  6:45 pm on Tuesday evening.

We will take checkins on this week's  DEN  using  CW  (MCW).  Set up the transmit speed for say  20 wpm.
Click your mouse at   800 Hz  on the waterfall.  That is the same audio pitch used by the PMRC  repeater CW ID.  Listening to   CW at  1500 Hz pitch would be annoying for most of us.

We will take checkins with MCW, but deliver any traffic with MFSK 32, centered on  1500 Hz  (so be careful to change frequency when we switch to traffic mode).   Keep your  RxID  on at all time, and check  the option of search total passband for RXID signals.  That is, right click on the RxID  button, at top of the FLDIGI screen, and choose  "search passband".  That way any transmit  TXID signal at either 800 Hz or  at  1500 Hz  will be detected at your  FLDIGI sound card, and will switch you to the proper mode.

CW is a mode that many can decode  "by ear/brain"  so of course, we may have some  REAL  CW  ops join us for this net.  You can also set up a code-practice oscillator and try sending CW by a hand key..... if you are brave.  Just hold the radio's MIC near the CW practice oscillator's headphones/speaker.  The tone may be something other than  800 Hz, but we will hear it and see it on the waterfall. Try to adjust the tone for 800 Hz if that is possible.  Well-sent  CW  (by hand or by keyer) is easily copied by the excellent FLDIGI  CW  demodulator.  I've copied W1AW code practice transmissions at  20 wpm with nearly  100%  accuracy.

So  CW  buffs..... come join us!!
Get that code practice oscillator out of the junk box and set it up.
We will aim to run the CW portion of the net at around  20 word/minute but any speed is acceptable.

Remember since we are using a voice repeater to always leave some time between transmissions (wait for the chime)  for any voice priority or emergency traffic to break into the net.  PMRC is a Mobile Amateur Radio Club, and priority is for any emergency traffic.



Allstar is a voice over IP communication mode based on the Asterisk PBX platform.  An analog type transceiver is connected to other Allstar nodes via the Internet.  Doug, WA3DSP, developed the code to run Allstar with an inexpensive Raspberry PI.  For more information see:

Thanks to Doug and the Philmont club for setting this up.


On a side note if anyone is interested in HF NBEMS nets there is a new group called Pa NBEMS Net.  To join the group click here:

Then click Join This Group.  NBEMS stands for Narrow Band Emergency Messaging System and the Pa NBEMS Net meets every Sunday morning at 0800L using Fldigi.  Barry, K3EUI, is the net manager.  We would like to see more participation from the DEN members.