<-[[.:start]]


====== CCIR493 Selcall ======

** HF Selcall Experiments **


===== Background =====

I became interested in HF selcall when I was looking for a way of setting up impromptu QSOs with specific stations, for doing tests etc., without the need for listening by ear for calls. Various ideas were considered for controlling an audio mute, and alerting the operator, on HF, but nothing seemed appropriate (CTCSS, DTMF etc) until I stumbled on CCIR493 HF Selcall, specifically designed to cope with conditions on the HF bands. 

The protocol was familiar, as it's very similar (but slightly simpler) than GMDSS DSC. This led to more reading and research. CCIR493 is widely used in Land Mobile HF SSB in Australia and in other countries which use HF SSB as a communications method. It seems largely unused in Europe. In Australia it is used on the networks set up to assist 4WD outback travellers, with Selcall used to initiate contact with the various base stations. 

Selcall's ''beacon'' and ''99 beacon'' functions can be used to check if a particular station is reachable before attempting a voice call. 

This seemed ideal.... down the rabbit hole of HF Selcall.....

==== Basic details ====

CCIR493 HF Selcall is a predecessor to GMDSS DSC used in Marine Radio. 

  * Two Tone FSK with 170Hz shift
  * 100baud signalling rate
  * Tone frequencies 1700 = 0, 1870 = 1 (tone centre = 1785)
    * compare with DSC: 1615 = 1, 1785 = 0 (tone centre = 1700, inverted shift)
  * Symbols are 10-bit words, 7 bit + 3 parity bits
  * Dotting pre-amble of alternating 1010..... 2 to 20 seconds depending on expected scan-group size
  * Same "symbol repeat after 4" RX/DX interleaving as DSC
  * Same phasing sequence as DSC
  * No overall Error Check Sum, unlike DSC

{{:public:radio:active:selcall_4_digit_ccir_493_4_hflink_a.jpg?800|}}

  * At its simplest a selcall transmission can be either:

  - Directed call to a specific address
    - ''Selcall'' = send a revertive signal over the air AND alert the remote operator. The ''FMT'' symbol = ''120''
    - ''Directed-Beacon'' = send revertive signal over the air, but do not alert remote operator. The ''FMT'' symbol = ''123''
  - ''99-beacon'' call to a group of addresses = all stations send revertive signal over the air, but do not alert remote operator. The ''99-beacon call'' is a special form of a directed selcall, with the ''FMT'' symbol of ''120'' and the final two digits of the destination address = ''99''. Receiving decoders understand to treat the call as a special type of ''beacon'' call despite the ''FMT'' being ''120'' (Selcall) 

The ''directed-beacon'' to a specific address will confirm if that station is reachable, without disturbing the operator. 

The ''99-beacon call'' confirms whether any station in the //group// are reachable - the //group// is "any station with the first two digits matching". The address used for the ''99-beacon call'' is ''XX99'', where ''XX'' is the leading digits of the desired group. For example, a group stations ''3610'', ''3602'', ''3603'', ''3654'' would all respond to a ''99-beacon call'' addressed to ''3699''
===== Jenal SC2 Mic =====

HF Selcall is widely used in Australia, and there is a large market for add-on Selcall devices (to convert non-selcall radios) there. One manufacturer of Selcall equipment is **JENAL**.

At the time of my first exploration of Selcall I found that the SC2 microphone seemed like the perfect solution. The SC2 had been out of production, but Jenal had just released a new batch and I bought TWO of them, allowing me to experiment in isolation, should I fail to find any other amateur stations suitably equipped.


  * {{ :public:radio:active:sc2prg7.pdf | SC2 Handbook}}

One SC2 microphone can be connected to a Xiegu G90 portable HF transceiver, capable of 20W pep, and the other SC2 can be connected to a home made 60m SSB transceiver, also capable of 20W PEP, at the main station. 

==== Scanning ====

The SC2 is capable of controlling the transceiver to scan, waiting for incoming selcall ''dotting'' signals, when it will pause the scan to decode any selcall message and act upon it as appropriate. Scan will resume after a certain period. The simplest scanning method is to pulse the ''channel up'' or ''channel down'' line present on most ham-grade transceivers on the mic-connector and thus the radio will step through its memory channels looking for selcall signals. 

FIXME

===== Previous Selcall Activity =====

In previous periods of activity with Selcall I have managed a few contacts and QSOs. Mainly with two stations who were already equipped with Barrett or Codan radios which can use CCIR493 "out of the box".

  * GM4WMM - with a Barrett 950. We successfully operated on a small set of predetermined channels in the 80m, 60m, 40m bands, scanning, and selecting the optimum channel using ''beacon'' calls.
  * [[https://www.qrz.com/db/F6EMT | F6EMT ]]- with a Codan FIXME. Made several contacts on 20m, some of them while mobile, initiated as random Selcall QSOs.

For 2023 I hope to find some more Selcall-equipped stations willing to try some experiments. 

===== Selcall Activity 2023 =====

FIXME

  * <todo #john:2023-04-30> Attach SC2 to Xiegu G90</todo>
  * <todo #john:2023-04-30>Set up 60m homebrew radio & amplifier & attach SC2 </todo>
  * <todo #john:2023-05-05>Install mobile whip on van for use with G90</todo>
  * <todo #john:2023-04-30>Make adaptor for IC-M710 to allow easy connection of SC2 in place of usual datamode interface, for access to more bands</todo>
  * <todo>Try to make contact with like minded experimenters for on-air tests</todo> 


**UPDATE** --- //John Pumford-Green 30/04/23 16:57//

** When not otherwise engaged I'll leave my main station IC-M710 monitoring ''14.343MHz'' or ''18.163MHz''  with Selcall ID ''3658''. I may not be able to respond directly to any calls the Selcall will send revertives (at 50W) for successful selcall or beacon calls to ''3658''or for 99-beacon calls to ''3699''**

For skeds please contact me by email - address at [[https://www.qrz.com/db/GM4SLV]]

I have re-enabled emails from the ''hf-link'' groups.io [[https://groups.io/g/hflink]] to see what's happening here - the only place where CCIR493 appears to be discussed/used.
===== Further Information =====

  * <del>[[https://youtu.be/Sbz8x2U-MqQ | My demonstration video ]]</del>
  * [[https://youtu.be/4CfKJiNFM3o | Q-Mac HF90 demonstration ]]
  * <del>[[https://youtube.com/playlist?list=PLQqFw4bopLF-ZJ6URtjXEAHlSpQrODwX-| My short YouTube playlist with some Selcall videos]]</del>
  * [[https://youtube.com/playlist?list=PLvMzk-zSmB2Z8bRJ6vO-jSiiazgTl6Fzo | Australia Travel Net How-To series playlist ]]

  * [[https://www.jenal.com/page2.htm]]
  * [[http://hflink.com/selcall/]]
  * [[http://hflink.com/selcall/directory/ | HFLink Ham Selcall directory ]]
  * [[https://www.sigidwiki.com/wiki/CCIR_493-4_Selcall]]
  * {{ :public:radio:active:ccir_493_selcall.pdf | A brief guide to CCIR493 what I wrote}}
  * {{ :public:radio:active:vks-737-map-a4-2020-01-02.pdf | Map of the VKS-737 base stations & their Selcall addresses }}
  * {{:public:radio:active:oz_map_5.jpg?linkonly| Map of the Bush Telegraph base stations VMS469}}
  
  * [[https://play.google.com/store/apps/details?id=com.blackcatsystems.selcall | Blackcat Android app for generating various Selcalls, including Barrett/Codan ]]

=== Code snippets ===


  * {{ :public:radio:active:selcal.zip | My Python2 Selcall TX encoder}}


++++ selcal_functions.py |

<code python>

# CCIR 493-4 Selcal Symbol Generator / CPFSK Modulator
# Wire2waves Ltd
# March 2015
# with CW ID for use on Amateur Radio bands

version = "v0.2"

# Imports
import numpy
import pyaudio
import struct
import time
from math import *

# quick and dirty CW Ident
# words per minute
wpm = 20
# dot period
cwdit = 1.2 / wpm
# dash period
cwdah = cwdit * 3

w_amp = (2**15) - 1

# define the output audio stream for the main data
p = pyaudio.PyAudio()
cpfsk_stream = p.open(format=pyaudio.paInt16, channels=1, rate=9600, output=1)

# make a second stream for the Tune carrier & cw ident
pt = pyaudio.PyAudio()
tunestream = pt.open(format=pyaudio.paInt16, channels=1, rate=9600, output=1)

pc = pyaudio.PyAudio()
cwstream = pc.open(format=pyaudio.paInt16, channels=1, rate=9600, output=1)

# convert text to symbol value using dictionaries
fmt_symbol_dict = { "sel" : "120", "bcn" : "123" }
cat_symbol_dict = { "rtn" : "100"}
eos_symbol_dict = { "req" : "117" }


# list containing Phasing Symbols in DX/RX order. 

phasing_symbol = [ "125", "109", "125", "108", "125", "107", "125", "106", "125", "105", "125", "104" ]

# Instead of doing bit-twiddling to convert each symbol
# value to its 10-bit parity protected word, which involves padding to full 7-bits, counting zeros,
# reversing the bit order, shifting bits and "ORing" in the parity bits
# we just use a dictionary containing the conversion between symbol value and its 10-bit parity protected word
#
parity_table = { 
"00" : "0000000111", "01" : "1000000110", "02" : "0100000110", "03" : "1100000101", 
"04" : "0010000110", "05" : "1010000101", "06" : "0110000101", "07" : "1110000100",
"08" : "0001000110", "09" : "1001000101", "10" : "0101000101", "11" : "1101000100", 
"12" : "0011000101", "13" : "1011000100", "14" : "0111000100", "15" : "1111000011", 
"16" : "0000100110", "17" : "1000100101", "18" : "0100100101", "19" : "1100100100", 
"20" : "0010100101", "21" : "1010100100", "22" : "0110100100", "23" : "1110100011", 
"24" : "0001100101", "25" : "1001100100", "26" : "0101100100", "27" : "1101100011", 
"28" : "0011100100", "29" : "1011100011", "30" : "0111100011", "31" : "1111100010", 
"32" : "0000010110", "33" : "1000010101", "34" : "0100010101", "35" : "1100010100", 
"36" : "0010010101", "37" : "1010010100", "38" : "0110010100", "39" : "1110010011", 
"40" : "0001010101", "41" : "1001010100", "42" : "0101010100", "43" : "1101010011", 
"44" : "0011010100", "45" : "1011010011", "46" : "0111010011", "47" : "1111010010", 
"48" : "0000110101", "49" : "1000110100", "50" : "0100110100", "51" : "1100110011", 
"52" : "0010110100", "53" : "1010110011", "54" : "0110110011", "55" : "1110110010", 
"56" : "0001110100", "57" : "1001110011", "58" : "0101110011", "59" : "1101110010", 
"60" : "0011110011", "61" : "1011110010", "62" : "0111110010", "63" : "1111110001", 
"64" : "0000001110", "65" : "1000001101", "66" : "0100001101", "67" : "1100001100", 
"68" : "0010001101", "69" : "1010001100", "70" : "0110001100", "71" : "1110001011", 
"72" : "0001001101", "73" : "1001001100", "74" : "0101001100", "75" : "1101001011", 
"76" : "0011001100", "77" : "1011001011", "78" : "0111001011", "79" : "1111001010", 
"80" : "0000101101", "81" : "1000101100", "82" : "0100101100", "83" : "1100101011", 
"84" : "0010101100", "85" : "1010101011", "86" : "0110101011", "87" : "1110101010", 
"88" : "0001101100", "89" : "1001101011", "90" : "0101101011", "91" : "1101101010", 
"92" : "0011101011", "93" : "1011101010", "94" : "0111101010", "95" : "1111101001", 
"96" : "0000011101", "97" : "1000011100", "98" : "0100011100", "99" : "1100011011", 
"100" : "0010011100", "101" : "1010011011", "102" : "0110011011", "103" : "1110011010", 
"104" : "0001011100", "105" : "1001011011", "106" : "0101011011", "107" : "1101011010", 
"108" : "0011011011", "109" : "1011011010", "110" : "0111011010", "111" : "1111011001", 
"112" : "0000111100", "113" : "1000111011", "114" : "0100111011", "115" : "1100111010", 
"116" : "0010111011", "117" : "1010111010", "118" : "0110111010", "119" : "1110111001", 
"120" : "0001111011", "121" : "1001111010", "122" : "0101111010", "123" : "1101111001", 
"124" : "0011111010", "125" : "1011111001", "126" : "0111111001", "127" : "1111111000" 
}

cw_table = {
"A" : ".-",
"B" : "-...",
"C" : "-.-.",
"D" : "-..",
"E" : ".",
"F" : "..-.",
"G" : "--.",
"H" : "....",
"I" : "..",
"J" : ".---",
"K" : "-.-",
"L" : ".-..",
"M" : "--",
"N" : "-.",
"O" : "---",
"P" : ".--.",
"Q" : "--.-",
"R" : ".-.",
"S" : "...",
"T" : "-",
"U" : "..-",
"V" : "...-",
"W" : ".--",
"X" : "-..-",
"Y" : "--.-",
"Z" : "--..",
"1" : ".----",
"2" : "..---",
"3" : "...--",
"4" : "....-",
"5" : ".....",
"6" : "-....",
"7" : "--...",
"8" : "---..",
"9" : "----.",
"0" : "-----",
" " : "",
"/" : "-..-.",
"?" : "..--..",
"+" : ".-.-."
}

#####################
# function definitions
#

##############
#  Tone generators (not used for data, but for Tune and CW signals)
#
# Setting the "cspace" and "lspace" amplitudes (pwr) to non-zero
# will produce FSK-style CW, as used in Beacons etc,

def sine(frequency, length, rate):
    length = int(length * rate)
    factor = float(frequency) * (pi * 2) / rate
    return numpy.sin(numpy.arange(length) * factor)#
#
# Generate a carrier to allow Auto-ATU to re-tune when changing frequency
# reduced amplitude, 3 seconds 
#
def tune_carrier(pwr):
    frequency = 1785
    length = 3
    rate = 9600
    chunks = []
    chunks.append(sine(frequency, length, rate))
    chunk = numpy.concatenate(chunks) * (w_amp * pwr)
    tunestream.write(chunk.astype(numpy.int16).tostring())

def dash(pwr):
    frequency=1900
    length=cwdah 
    rate=9600
    chunks = []
    chunks.append(sine(frequency, length, rate))
    chunk = numpy.concatenate(chunks) *  (w_amp * pwr)
    cwstream.write(chunk.astype(numpy.int16).tostring())    
    
def dot(pwr):
    frequency=1900
    length=cwdit
    rate=9600
    chunks = []
    chunks.append(sine(frequency, length, rate))
    chunk = numpy.concatenate(chunks) *  (w_amp * pwr)
    cwstream.write(chunk.astype(numpy.int16).tostring())  

def cspace(pwr):
    frequency=1700
    length=cwdit
    rate=9600 
    chunks = []
    chunks.append(sine(frequency, length, rate))
    chunk = numpy.concatenate(chunks) *  (w_amp * pwr)
    cwstream.write(chunk.astype(numpy.int16).tostring())     

def lspace(pwr):
    frequency=1700
    length=cwdah
    rate=9600
    chunks = []
    chunks.append(sine(frequency, length, rate))
    chunk = numpy.concatenate(chunks) *  (w_amp * pwr)
    cwstream.write(chunk.astype(numpy.int16).tostring())      
#
#   
################################

def make_call(cw_table, call):
    callsign = ""
    for i in call:
        callsign += cw_table[i]
        callsign += "s"        
    return callsign
        
def cwid(call, pwr):
    callsign = make_call(cw_table, call)
    for i in callsign:
        if i == "-":
            dash(pwr)
            cspace(pwr)
        elif i == ".":
            dot(pwr)
            cspace(pwr)
        elif i == "s":
            lspace(pwr)
            
###########


# split a 4 digit Selcal into two 2-digit symbols
# resulting symbols are returned as a list
def sel_id_symbol(sel_id):
    sel_id_list = [(sel_id[i:i+2]) for i in range(0, len(sel_id), 2)]    
    return sel_id_list


# build the basic Call:
# Selcal messages are of the form:  "fmt to_id cat self_id eos eos eos"

def build_call(f_s, a_s, c_s, s_s, eos_s):

    sel_call = []
    
    sel_call.append(f_s)
    
    for i in a_s:
        sel_call.append(i)
    
    sel_call.append(c_s)

    for i in s_s:
        sel_call.append(i)

    sel_call.append(eos_s)
    
    sel_call.append(eos_s)
    sel_call.append(eos_s)
    
    return sel_call

    
# interleave the symbols into DX and RX sequence 
# at the same time convert between symbol value and
# 10-bit parity word by looking in the parity_table dictionary.

def interleave(parity_table, phasing, sel_list):
    
    symbol_count = len(sel_list)
    
    sel_dxrx = []
    # interleave the phasing sequence
    for p in range(0,12):
        sel_dxrx.append(parity_table[phasing[p]]) #dxrx
    
    # add dx and rx copies of the format symbol
    sel_dxrx.append(parity_table[sel_list[0]]) #dx
    sel_dxrx.append(parity_table[sel_list[0]]) #rx
    
    # add the DX copy of the the to_ID
    sel_dxrx.append(parity_table[sel_list[1]]) #dx
    
    # add another RX copy of the format symbol
    sel_dxrx.append(parity_table[sel_list[0]]) #rx
    
    # add the DX copy of the category symbol
    sel_dxrx.append(parity_table[sel_list[2]]) #dx
    
    # loop through the remaining symbols to add the RX and DX versions 
    for i in range(0,symbol_count-3):
        sel_dxrx.append(parity_table[sel_list[i]]) #rx
        sel_dxrx.append(parity_table[sel_list[i+3]]) #dx
    
    # add a final DX and RX copy of the EOS symbol
    sel_dxrx.append(parity_table[sel_list[-1]])
    sel_dxrx.append(parity_table[sel_list[-1]])    
    
    # sel_dxrx is a list of 10-bit words, as ones and noughts, for the complete message
    return sel_dxrx

    
# Make a 600-bit dotting period of alternating 1/0 in a string

# Selcal dotting periods often 6 seconds (and up to 20 seconds in some
# instances) to allow for capturing scanning radios. 
# We send 300 bits / 6 seconds for now, pending a decision to extend or reduce the dotting period.

# Append to the string each 10-bit interleaved word, to create a string of 
# ones and noughts.

# return a string of ones & noughts representing the complete message

def make_bitstream(sel_dxrx):
    sel_bitstream= "10"  * 300 # dotting
    for i in sel_dxrx:
        sel_bitstream += i
    return sel_bitstream

    
# DSC and Selcall use tone spacing and baud rate that prevents the use of 
# "Sunde's FSK" method to create glitch-less bit transitions.
#
# To minimize bandwidth it's necessary to use "Continuous Phase FSK" which
# has a smooth transition of the waveform at the bit boundary. The method used is time-consuming
# as we have to create each audio sample based on the phase-advance of each bit-period and 
# store them in a buffer before sending them out to the soundcard via PyAudio.
# 
# This function is courtesy of Bill Lionheart : billlionheart@gmail.com
#
# Make the CPFSK-modulated sample values, pack them into a list, and convert to a string 
# to feed PyAudio  
#

def modulate(fmsg, fcarrier, f0, f1, fsample, baud, amp):
    
    if amp > 1.0:
       amp = 1.0
       
    sel_amp =  (w_amp * amp)
    
    mlen = len(fmsg)

    mtime = mlen/baud  

    nsamp = int(round(fsample*mtime))

    deltaT = 1.0/fsample

    ph=0
    
    y = [0] * nsamp
    
    for i in range(nsamp): # i = sample number
    
        thisbit = int(floor((i/float(nsamp))* mlen)) 
        
        # "thisbit" is the index number of the data-bit being modulated,
        # the same data-bit is used for "the number of samples which occupy 1 bit period"
        
        if fmsg[thisbit]:
            f = f1 
        else:
            f = f0 
            
        # if this bit is a 1 then f = mark-freq, else f = space-freq
        
        ph +=  2*pi*(fcarrier + f)*deltaT
        
        # phase advances during sample period according the actual mark or space freq
        # when the bit changes between 1 and 0, the phase advance in deltaT is small, and
        # continuity in phase is achieved. The signal then starts to advance
        # in phase according to the new frequency appropriate the the bit (one or nought)
        #being sent.
        
        # reset phase to zero every 360 degrees
        if ph> 2*pi: 
            ph = ph - 2*pi
      
        y[i]=sel_amp*(sin(ph)) # y is an 8-bit value
        # y[i] is the current sample's amplitude - the "sin of current accumulated phase"
    
    wave_list = []
    for v in y:
        vp = struct.pack('h',v)
        wave_list.append(vp)
    wavestring = ''.join(wave_list)
    
    return wavestring
   
 
# Take the message to be sent and
# 1) interleave
# 2) make bitstream as a string
# 3) convert to list, for the CPFSK modulator function, 
# 4) calculate the sample values using the "modulate()" function
# 5) write the string of sample values to pyaudio


def transmit_sel(sel_call, pwr):
    #
    # 1) interleave the message and phasing DX and RX symbols together, and also convert to 10-bit parity words
    sel_dxrx = interleave(parity_table, phasing_symbol, sel_call) 
   
    # 2) create a string with the ones and noughts representing the full message
    sel_bitstream = make_bitstream(sel_dxrx)
    
    # 3) convert the string into a list, to feed the CPFSK modulator
    bitstream_list = [int(sel_bitstream[i:i+1]) for i in range(0, len(sel_bitstream), 1)]
    
    # 4) get a list of sample values from the CPFSK modulator
    #
    # arguments for modulate() : (source of message_bits(a list), f-centre, space_dev, mark_dev, sample_rate, baud_rate, amplitude)
    # returns a string of 8-bit signed values to feed PyAudio
    
    wave = modulate(bitstream_list, 1785, -85, +85, 9600, 100.0, pwr)
    
    # 5) make some noise...
    
    cpfsk_stream.write(wave)
    
    return

           
</code>

++++

++++ selcal_gui.py |

<code python>
# Wire2waves Ltd
# CCIR 493-4 Selcal Generator & Modulator
# Generic, non-TX GUI


from Tkinter import *
from selcal_functions import *
import threading
import Queue
import time

version = "v0.2"


class Application(Frame):
    def __init__(self, master):
        """ Initialize frame"""
        Frame.__init__(self, master)
        self.grid()
        self.create_widgets()
        
        # we manage the three sound-producing functions in Threads, run at startup but only produce
        # output when their Queues are set to "1"
        self.selqueue = Queue.Queue()
        self.tunequeue = Queue.Queue()
        self.cwqueue = Queue.Queue()
        self.tunequeue.put(0)
        self.selqueue.put(0)
        self.cwqueue.put(0)
        t1 = threading.Thread(target = self.tune)
        t1.setDaemon(True)
        t1.start()
        c1 = threading.Thread(target = self.send_cwid)
        c1.setDaemon(True)
        c1.start()
        d1 = threading.Thread(target = self.send_sel)
        d1.setDaemon(True)
        d1.start()
        
        
    def create_widgets(self):
        
        ###### 
        #
        # The Address Entry Fields
        self.to_l = Label(self, width = 15, text = "To ID", fg = 'red').grid(row = 0, column = 0, sticky = W)
        self.to_sel_id_e = Entry(self, width = 10, fg = 'red')
        self.to_sel_id_e.grid(row = 0, column = 1, padx = 5, pady = 5, sticky = W)
        self.to_sel_id_e.insert(0, "3922")
        
        
        self.from_l = Label(self, width = 15, text = "Self ID", fg = 'blue').grid(row = 1, column = 0, sticky = W)
        self.from_sel_id_e = Entry(self, width = 10, fg = 'blue')
        self.from_sel_id_e.grid(row = 1, column = 1, padx = 5, pady = 5, sticky = W)
        self.from_sel_id_e.insert(0, "3921")
        
        ###################
        #
        # The "Format" selection radio buttons
        self.fmt = StringVar()
        self.fmt_l = Label(self, width = 15, text = "Format").grid(row = 5, column = 0, sticky = W)
        self.sel_r = Radiobutton(self, text = "Sel", variable = self.fmt, value = "sel")
        self.sel_r.grid(row = 5, column = 1, sticky = W)
        self.bcn_r = Radiobutton(self, text = "Bcn", variable = self.fmt, value = "bcn")
        self.bcn_r.grid(row = 5, column = 2, sticky = W)
        #self.fmt_e = Entry(self, width = 10, fg = 'blue')
        #self.fmt_e.grid(row = 5, column = 1, padx = 5, pady = 5, sticky = W)
        #self.fmt_e.insert(0, "120")
        
        #
        # click the "SEL" radio button
        self.sel_r.invoke()
        #
        ########
        
        ######
        #
        # The "Category" selection radio buttons
        
        self.cat = StringVar()
        
        self.cat_l = Label(self, width = 15, text = "Category").grid(row = 6, column = 0, sticky = W)
        self.saf_r = Radiobutton(self, text = "Routine", variable = self.cat, value = "rtn")
        self.saf_r.grid(row = 6, column = 1, sticky = W)
        #self.cat_e = Entry(self, width = 10, fg = 'blue')
        #self.cat_e.grid(row = 6, column = 1, padx = 5, pady = 5, sticky = W)
        #self.cat_e.insert(0, "100")
        
        
        # For selcal we may require other categories, but at present only "Routine" is used
        #self.urg_r = Radiobutton(self, text = "Urgent", variable = self.cat, value = "urg")
        #self.urg_r.grid(row = 6, column = 2, sticky = W)
        #self.dis_r = Radiobutton(self, text = "Distress", variable = self.cat, value = "dis")
        #self.dis_r.grid(row = 6, column = 3, sticky = W)
        
        # click the "Safety" radio-button
        self.saf_r.invoke()
        #
        ########
        
        ####
        #
        # The "EOS" selection radio buttons
        
        self.eosv = StringVar()
        self.eos_l = Label(self, width = 15, text = "EOS").grid(row = 9, column = 0, sticky = W)
        self.req_r = Radiobutton(self, text = "REQ", variable = self.eosv, value = "req")
        self.req_r.grid(row = 9, column = 1, sticky = W)
        #self.eos_e = Entry(self, width = 10, fg = 'blue')
        #self.eos_e.grid(row = 9, column = 1, padx = 5, pady = 5, sticky = W)
        #self.eos_e.insert(0, "117")
        
        # leave these in case other EOS symbols would be useful in the future 
        #self.ack_r = Radiobutton(self, text = "ACK", variable = self.eosv, value = "ack")
        #self.ack_r.grid(row = 9, column = 2, sticky = W)
        
        #self.eos_r = Radiobutton(self, text = "EOS", variable = self.eosv, value = "eos")
        #self.eos_r.grid(row = 9, column = 3, sticky = W)
        
        # click the "REQ" radio button
        self.req_r.invoke()
        #
        ###########
        
        
        ###########
        #
        # The "do something" buttons
        
        self.go_b = Button(self, text = "Send Selcal", command = self.selqueue_on)
        self.go_b.grid(row = 10, column = 0, sticky = W+E)
        
        self.tune_b = Button(self, text = "Tune", command = self.tunequeue_on)
        self.tune_b.grid(row = 13, column = 0, sticky = W+E)
        
        self.cw_call_e = Entry(self)
        self.cw_call_e.grid(row = 14, column = 1, columnspan = 2)
        #
        # The CW Text is pre-set, but can be edited as required on the GUI
        self.cw_call_e.insert(0, "   de GM4SLV   ")
        
        self.cw_b = Button(self, text = "Send CW ->", command = self.cwqueue_on)
        self.cw_b.grid(row = 14, column = 0, sticky = W+E)
        
        ######
        #
        # The display of Selcal Symbols
        #
        
        self.sel_title = Label(self, text = "Sending Selcal Symbols: " , fg = 'blue').grid(row = 16, column = 0)
        
        sel_call_f = Frame(self, relief = GROOVE, borderwidth = 2, pady = 5)
        sel_call_f.grid(row = 17, column = 0, columnspan = 5, padx = 5, pady = 5, sticky = W+E)
        
        
        self.sel_label = StringVar()
        self.sel_l = Label(sel_call_f, textvariable = self.sel_label, fg = 'blue', height = 2, wraplength = 350, anchor = W)
        self.sel_l.grid(row = 0, column = 0)
        #
        #####
        
    
    # When a Tune is required we call tunequeue_on() which puts a "1" into the queue.
    # The queue is read by tune() which is running constantly (while True:) in a thread. 
    # If a "1" is found the tune_carrier() function is triggered
    # then tunequeue_off() will put a "0" in the queue which will inhibit any further
    # tune signals. 
    
    # Since the Tune, CWID and Selcal Transmit all run in their own threads, with their own queues
    # it's possible to do all three functions at once, and still retain an active GUI
    # this may not be "the right way" to do this, but it works...
    
    def tunequeue_on(self):
        self.tunequeue.put(1)
        
    def tunequeue_off(self):
        self.tunequeue.put(0)
        
        
    def tune(self):
        
        while True:
            t_on = self.tunequeue.get()
            if t_on == 1:   
                pwr = 0.7
                tune_carrier(pwr)
                self.tunequeue_off()
    
    
    def cwqueue_on(self):
        self.cwqueue.put(1)
    def cwqueue_off(self):
        self.cwqueue.put(0)
    
    def send_cwid(self):
        while True:
            c_on = self.cwqueue.get()
            if c_on == 1:
                pwr = 0.7
                call = self.cw_call_e.get().upper()
                cwid(call, pwr)
                self.cwqueue_off()
                
    def selqueue_on(self):
        self.selqueue.put(1)
    def selqueue_off(self):
        self.selqueue.put(0)
     
    def send_sel(self):
        
        while True:   
            go = self.selqueue.get()
            if go == 1:
                a_sel_id = self.to_sel_id_e.get()
                s_sel_id = self.from_sel_id_e.get()
                fmt = self.fmt.get()
                cat = self.cat.get()
                eos = self.eosv.get()
                pwr = 0.7
                
                # restrict to 4-digit 493-4
                if len(a_sel_id) != 4:
                    continue
                if len(s_sel_id) != 4:
                    continue
                    
                # convert the format, category and eos to the appropriate symbol values
                fmt_symbol = (fmt_symbol_dict[fmt])
                #fmt_symbol = self.fmt_e.get()
                
                cat_symbol = (cat_symbol_dict[cat])
                #cat_symbol = self.cat_e.get()
                
                eos_symbol = (eos_symbol_dict[eos])
                #eos_symbol = self.eos_e.get()
                
                # convert the 4-digit selcal IDs into two 2-digit symbols
                a_symbol = sel_id_symbol(a_sel_id)
                s_symbol = sel_id_symbol(s_sel_id)
                
                # build the call by joining the symbol values into a list
                sel_call = build_call(fmt_symbol, a_symbol, cat_symbol, s_symbol, eos_symbol)
                
                #we want the basic selcal message returned to us, to display on the GUI
                self.sel_label.set(sel_call)
                
                # turn the selcal queue off to stop further transmissions
                self.selqueue_off()
                
                # then we pass the selcal list and required "power" into "transmit_sel() which does the rest...
                transmit_sel(sel_call, pwr) 
            
       
if __name__ == '__main__':
    root = Tk()
   
    root.geometry("350x350+10+10")
    root.title("GM4SLV HF CCIR 493-4 Selcal " + version)
    root.resizable(0, 0)
    app = Application(root)
    
    
    root.mainloop()

</code>

++++


--- //John Pumford-Green 29/04/23 11:42//


Last Modified : ~~LASTMOD~~

{{tag>radio selcall}}