
[ ANARTS - Australian National Amateur Radio Teletype Society ]

ANARTS News 30/10/94

This   is  VK2TTY  VK2TTY  the  official  station  of   the 
Australian   National   Amateur  Radio  Teleprinter   Society, 
which includes  all digital modes,   with the weekly broadcast  
on the following frequencies:

  3.545 MHz                  0930 UTC     VK2BQS (Jim)
  7.045 MHz -3               0030 UTC     VK2CTD (Col)
 14.070 MHz (amtor/fec)      0030 UTC     VK2DPM (Alan)      
 14.091 MHz                  0030 UTC     VK2BQS (JIM)
146.675 MHz             0030/0930 UTC     VK2JPA (PAT)
144.850 MHz (ax25 bbs)                    VK2JPA AT VK2RWI
                                            (or VK2AAB)
146.675 MHz (rtty mmbbs/repeater)          VK2RTY
   

Bits, bauds, baubles and bangles

by Jim Piper, KD6YKL

Back  in  the days of yore  (not  mine,  yore),  when  digital 
communications  meant interrupted continuous wave (CW),  folks 
measured  transmission rates in worde per  minute.  Then  came 
Teletype   and   the  favored    -yardstick- for   information 
transmission rates became the baud (after French keyboard pio-
neer Emile Baudot).

As  speed advanced to 300 baud,  that measure of  transmission 
rate  over  a  digital  communications link (which  can  be  a 
telegraph  wire or a radio path) served well.  But  technology 
continued  to  press forward.  As rates passed 1200  bits  per 
second (bps), 300 baud began to seem smallish.

Todays  fibre-optic  lines  allow data rates as  high  as  2.5 
gigabits per second (2,500,000,000 bps).  Even our  relatively 
narrow UHF ham bands can easily carry data at 9,600 bps.

Most  hams  use baud to describe data rate regardless  of  the 
transmission  medium.  Yet  confusing baud and bps clouds  the 
discussion  of  data transmission rates.  (Its a  little  like 
asking what time it is when you want to know how much time  is 
left).

The problem with the indiscriminate use of the term baud stems 
from a misunderstanding of its meaning.  According to Webster, 
the IEEE and the ARRL,  a baud is - a unit of signalling speed 
equal to one discrete condition or event per second.  In CW, a  
-discrete  signalling  condition-  occurs  each time  a  radio 
transmitter is keyed on or off.

How  does this relate to baud/ If you key your transmitter  at 
the rate of 5 words per minute and the average word length  is 
six  characters,  and  each character has an average of  three 
dits and dahs, you are producing 180 symbols per minute (5 WPM 
x  6 x 6).  You could say that you were transmitting CW  at  6 
baud  because you are transmitting an average of 360  discrete 
conditions per minute, or 6 per second. Of course, we normally 
dont describe CW rates in baud, but in words per minute.

One  often  hears  packet  radio  and  voice  frequency  modms 
discussed  in  terms of baud.  The actual rate at  which  data 
(i.e., dugutal information) flows depends on the ratio of bits 
per  baud.  Baud rate and bit rate are equal only at speeds of 
300 baud and below, and obly for FSK modulation without parity 
bits.  Other  modulation  schemes sudh as  phase-sgift  keying 
(PSK, BPSK, and QPSK), CLOVER, etc., stuff more bits into each 
baud.  Thats why, for the sake of accuracy. I encourage you to 
use  the  much less confusing bits-per-second  measure  rather 
than the baud.
 
(Just kidding about the baubles and bangles).

Reprinted from the Digital Journal October 1994


          -----------------------------------------


                      IPS WEEKLY REPORT 
                      -----------------

                   21 OCTOBER - 27 OCTOBER

ISSUE No 43

DATE OF ISSUE: 28 OCTOBER 1994

INDICES:

DATE     21    22    23    24    25    26    27

10CM     88    86    84    82    89    93    93
A         1    18    37    24     8     8   ( 7 ESTIMATED)
T        27    37    15    15   -21     7    38


SOLAR ACTIVITY WAS VERY LOW 21ST,  AND 26TH-27TH OCTOBER,  AND 
LOW 22ND-25TH.

THE  GEOMAGNETIC  FIELD  AT  LEARMONTH (WA)  WAS  QUIET  21ST, 
INCREASING TO UNSETTLED TO ACTIVE ON 22ND.  ON 23RD THE  FIELD 
WAS AT ACTIVE TO MINOR STORM LEVELS, RETURNING TO UNSETTLED ON 
24TH, QUIET ON 25TH, AND QUIET TO UNSETTLED 26TH-27TH OCTOBER.

IONOSPHERIC   F2  CRITICAL  FREQUENCIES  WERE  NEAR  PREDICTED 
MONTHLY VALUES 21ST-24TH OCTOBER, THEN UP TO 20 PER CENT BELOW 
PREDICTED VALUES ON 25TH-26TH.  ON 27TH THE FIELD WAS ENHANCED 
15-30 PER CENT DURING LOCAL NIGHT.


             FORECAST (28 OCTOBER - 03 NOVEMBER)

SOLAR:        LOW

GEOMAGNETIC:  ACTIVE  TO  MINOR STORM LEVELS  ON  30  OCTOBER, 
              UNSETTLED TO ACTIVE OTHERWISE.

IONOSPHERIC:  NEAR  NORMAL  UNTIL  31  OCTOBER,  15  PER  CENT 
              DEPRESSIONS EXPECTED THEREAFTER.


COURTESY OF IPS RADIO AND SPACE SERVICES


           ---------------------------------------

VK2SG RTTY DX NOTES 21 OCT 94

VK2SG RTTY DX NOTES FOR WEEK ENDING 21 OCT 1994 (BID RTDX1021)

OUR  THANKS  THIS WEEK GO TO DJ3IW AND THE CENTRAL  EUROPE  DX 
CLUSTER  DB0SPC,   I5FLN,  JA3MNP,  WB2CJL,  W5KSI,  W6/G0AZT, 
WA0PUJ,  WF5T,  AND  THE NJ0M NODE OF THE MINNESOTA DX  PACKET 
CLUSTER NETWORK.


BANDPASS:

FRIDAY 14
0020-14085 8R1TT QSL P.O. BOX 5194, RICHMOND, CA 94805
0140-7082  8R1TT
1342-21087 3DA0CA QSL TO JON RUDY, BOX 329, MBABANE, SWAZILAND
1409-21052 8R1TT
1836-14087 PJ7/N6OXR
1949-14086 ET3SID
2053-14086 VK2KM
2250-14091 Z21HD

SATURDAY 15
0227-7090  KP2N
0334-7084  8R1TT
0341-3603  N9NCX
0819-14076 3X0DEX
0836-14085 9K2HN
1218-14085 8R1TT
1218-14088 PJ7/N6OXR
1238-14084 OH2GI
1247-14087 8R1K
1249-14083 RU3AT
1426-14091 VS6WV
1446-14084 5H3JA
1540-14087 JW0I
1558-21089 Z21HD
1647-14080 V85GA
1650-21082 ZS6ARF
1916-21092 5W1MM
2148-21092 V63AS QSL JA3JA
2347-21078 A35MW
2349-21097 VK6GOM

SUNDAY 16
0544-7035  ZL3GQ
0957-21092 TZ6FIC
1001-21091 9Q5ARJ
1004-21081 A71EY
1158-7031  5W1MM
1210-7030  V63AS
1218-21093 YB2CPO
1234-21083 8R1TT
1314-21084 OS6AA
1534-21094 KP2N
1612-21082 SV1NA
1617-21078 SV2FN
1705-21087 Z21HD
1803-14089 9K2WA
1824-21091 5W1MM
1942-21085 V63AS
2057-21086 A35CT
2303-21081 AH6JL
2311-21092 NH6XM

MONDAY 17
1208-14086 OS6AA
1223-14083 9K2IC
1231-14084 8R1TT
1238-14086 UT5PF
1642-21088 GW3SFU
2137-14084 NL7CH

TUESDAY 18
1422-14089 S53X
1458-21081 8R1TT
1635-21081 3DA0CA
1827-14088 OD5PL

WEDNESDAY 19
0017-14091 UA0SMF
0040-14086 ZP6CC
0125-14086 JT1CS
1205-14083 UX2FXF QSL VIA G3WKI
1225-14086 CU1AC
1229-14086 CU1EC
1435-14087 VQ9JB
1751-21084 8R1TT

THURSDAY 20
1257-14085 CU1AC

NOTES OF INTEREST:

NAMIBIA - THE TEAM OF N9NS,  N0AFW,  NH6UY,  AH9B,  AND WA0PUJ 
WILL  OPERATE V51/ FROM 23 OCTOBER THROUGH 6 NOVEMBER.  BEFORE 
AND AFTER THE CQWW SSB CONTEST,  IN WHICH THEY WILL OPERATE AS 
V51T, LOOK FOR THEM ON RTTY. QSL ALL CONTACTS TO WA2FIJ.

UGANDA - PAUL,  WF5T WILL AGAIN OPERATE FROM UGANDA DURING THE 
MONTH OF NOVEMBER, AS 5X1XT, ON BOTH CW AND RTTY. QSL TO WF5T.

LAOS - LOOK FOR MINORU, JA3MNP BETWEEN 20-27 OCTOBER OPERATING 
AS XW3MNP. QSL TO P.O. BOX 59, KYOTONISHI 616, JAPAN.

FOR  NEXT  WEEK'S BULLETIN,  SEND YOUR BANDPASS AND  NOTES  OF 
INTEREST TO LUCIANO, I5FLN AT ZS5S.ZAF.AF.

GOOD HUNTING ES 73 DE JULES W2JGR AT W5KSI.#NOLA.LA.USA.NA.

(VIA HF AMTOR)

          -----------------------------------------
Apologies, but we do not have the ARRL DX this week at time of 
writing and despatching the news. Next week, we hope.

         -------------------------------------------
Society information

The Society may be contacted at :  PO Box 860, Crows Nest 2065 
Australia,   for   such  matters  as  membership  and  general 
enquiries.  Enquiries  can  also  be made  by  packet  to  the 
President  (Col)  VK2CTD, or the  Secretary  (Pat) VK2JPA at 
VK2RWI.
  
News  items  may  be  sent to  Broadcast  Officer  PO  Box  60 
Blacktown  2148 Australia,  or by packet to VK2JPA at  VK2RWI. 
Email addresses for the Broadcast Officer are : 

patl(at)pitt.conmusic.su.oz.au  

The  Society welcomes news items on any digital subjects  from 
anywhere in the broadcast coverage area.  We are looking  for-
ward  to news from your areas to let other  amateurs know what 
you are doing in the hobby. Hope to hear from you.

73s de Pat VK2JPA Broadcast Officer 
That concludes the broadcast for this morning/evening.

