SKYWARN Newsletter #24
Hello to all...
SKYWARN Training Update...
Brief SKYWARN Talk at the NSRA Meeting...
Sending the SKYWARN Document to Those Who Couldn't Attend the Meeting...
Changes in the Eastern Mass. ARES/RACES/SKYWARN Homepage...
Informal Meeting for the Fairhaven WX Net Saturday February 22nd...
Formal Meeting for the Fairhaven Weather Net Saturday April 26th...
Obtaining information on Nets from Across Southern New England...
Snowstorm About to Affect the Region...
Changes in the Severe WX Watch Format from the Storm Prediction Center...
APRS Documentation Series (Final Part)...
***Newsletter Issued: 2/17/97
SKYWARN Training Update...
Here is an update of the SKYWARN Training Sessions to date:
Carl, N1FYZ, has confirmed Thursday March 22nd at the Brockton VA
Hospital from 6:30 PM-9:45 PM. Thanks to Carl for obtaining this site.
North Shore: Carl, N1FYZ, is working on getting the VA Hospital in
Bedford, MA for SKYWARN Training.
Also, Terry Stader, MEMA Area I Radio Officer, is assisting
in securing MEMA Area I headquarters for possible SKYWARN
training.
Boston Area: Awaiting word from NUARC on SKYWARN Training at Northeastern
University.
Southern NH: Awaiting word from Don Dillaby and David Day on a date to
use the Nashua Town Hall for SKYWARN Training.
Connecticut: Awaiting a date to use the Canton High School in Canton
Connecticut for SKYWARN Training.
Western RI: Awaiting word from N1JMA, Martin Mendelson, and K1KYI,
Rick Fairweather, on SKYWARN Training in the Warwick RI
area.
We are rapidly approaching a full SKYWARN Training Schedule for this
year, and the devotion and work of all Amateur Radio Operators, Weather
Spotters, ARES and Emergency Management people are the reason for it.
Thanks to all for their assistance in obtaining SKYWARN training for
the region.
Brief SKYWARN Talk at the NSRA Meeting...
Phil Night and myself gave a brief presentation on what the new
145.47 Danvers Repeater SKYWARN Net's function will be. It will
provide a once a week net to discuss SKYWARN, Weather, and Amateur
Radio happenings as well as activate to report severe weather to
NWS Taunton as required.
Brochures were handed out and extras were left with NSRA President
Tony Penta. The NSRA club was very hospitable and I want to thank
the NSRA club for having me there and for allowing a SKYWARN
net to take place on their 145.47 Danvers Repeater.
The net will begin once a week, every Wednesday at 8 PM, starting
on Wednesday February 19th again on the 145.47 Danvers Repeater.
Sending the SKYWARN Document to Those Who Couldn't Attend the Meeting...
I have sent out 20 documents during the past week and plan on getting
the rest of the documents sent out by the end of this week.
Changes in the Eastern Mass. ARES/RACES/SKYWARN Homepage...
I fixed some link problems in the SKYWARN Weather Center links section.
Also, I added some additional Amateur Radio links in the Miscellaneous
section, as well as additional SKYWARN and ARES links in the Links
to other SKYWARN and links to other ARES Web page sections.
Informal Meeting for the Fairhaven WX Net Saturday February 22nd...
An informal meeting of the Fairhaven WX Net will occur this Saturday,
and Hank Riley of the Fairhaven Weather Net Commitee issued this email
earlier this week.
Well, this coming week by popular demand the weather net
reconvenes at the site of the original get together.
Hope to see you at Cronin's North at 1998 Acushnet Avenue
across from the east boundary of Brooklawn Park in New Bedford.
This will be Saturday, Feb. 22, from 12:00 noon to about 2:00
PM.
Bring your weather stuff or bring your weather stories to share
in this very informal setting.
Text directions to Cronin's North, the location for this Saturday's
FRWN gettogether, are now available at the web.
I expect a full map sketch to be there by late Wednesday.
The text and/or map can be emailed upon request.
Hank, N1LTV
h1riley@umassd.edu
www.geocities.com/capecanaveral/3161
Formal Meeting for the Fairhaven Weather Net Saturday April 26th...
A formal meeting of the Fairhaven Weather Net will be held on Saturday
April 26th at Noon at the Southworth Library. It will feature a slide
show from the Mount Washington, New Hampshire observatory. More details
as we get closer to the date of the meeting.
Obtaining information on Nets from Across Southern New England...
Do you have a weekly net that meets in your area? Have you had
a SKYWARN Activation recently. Send me a report of your weekly
net and what was discussed, or send me a report of what happened
during your SKYWARN Activation and will put it in the newsletter.
A complaint by some is that this newsletter is mostly South Coast
oriented, so I'd like to try to give out info on other weather
and SKYWARN nets from around Southern New England.
Snowstorm About to Affect the Region...
As of this writing, A Winter Storm Warning has been issued for South
Coastal Massachusetts, and Cape Cod and the Islands, with a Winter
Weather Advisory issued for the rest of Southern New England. 4-8
inches of snow is expected in South Coastal Massachusetts and the Cape
with 2-5 inches expected elsewhere in Southern New England. A review
of this event will appear in the next SKYWARN Newsletter.
Changes in the Severe WX Watch Format from the Storm Prediction Center...
This information was obtained from the SKYWARN email list.
ZCZC WSHPNSWSH ALL
TTAA00 KWSH DDHHMM
PUBLIC INFORMATION STATEMENT..ALSO NAT. TECH. INFO. MESSAGE 97-09
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
300 PM EST THU FEB 13 1997
TO: NATIONAL WEATHER SERVICE/NWS/ EMPLOYEES...FAMILY OF
SERVICES/FOS/SUBSCRIBERS...NOAA WEATHER WIRE
SERVICE/NWWS/SUBSCRIBERS...OTHER NWS CUSTOMERS
FROM: DONALD R. WERNLY...CHIEF...CUSTOMER SERVICE
SUBJECT: CHANGES IN FORMAT OF THE CONVECTIVE WATCH
NARRATIVE EFFECTIVE APRIL 15 1997
BEGINNING APRIL 15 1997 AT 600 AM CDT /1100 UNIVERSAL TIME
COORDINATED /UTC/ ...CONVECTIVE WATCH NARRATIVE PRODUCTS ISSUED
BY THE STORM PREDICTION CENTER /SPC/ AT NORMAN OK HAVE A NEW
FORMAT...PROVIDING SEVERAL IMPROVEMENTS OVER THE CURRENT VERSION.
O THE PRODUCT NOW INCLUDES BOTH BEGINNING AND ENDING
TIMES OF THE WATCH
O TECHNICAL INFORMATION HAS BEEN SEPARATED FROM THE NON-
TECHNICAL INFORMATION...WITH THE LATTER SITUATED NEAR
THE TOP OF THE PRODUCT;
O INSTEAD OF "A..." "C..." "D..." ETC... PARTS OF THE WATCH
NOW ARE IDENTIFIED WITH KEY WORDS "DISCUSSION"... "OTHER
WATCH INFORMATION..." AND "AVIATION"
O PLAIN LANGUAGE IS USED TO DESCRIBE THE POTENTIAL FOR
HAIL SIZE AND THUNDERSTORM WIND
O THE TERM "STORM MOTION VECTOR..." WHICH IS MORE DESCRIPTIVE
AND SCIENTIFICALLY ACCURATE...REPLACES "MEAN WIND VECTOR"
O LATITUDE/LONGITUDES OF WATCH BOX END POINTS ARE PLACED AT
THE BOTTOM AS WELL AS AT THE TOP OF THE PRODUCT. THIS
ALLOWS CUSTOMERS TO PLOT THE BOX USING COMPUTER SOFTWARE.
THESE CHANGES ARE DESIGNED TO ALLOW FOR QUICKER AND EASIER
READING OF WATCH PRODUCTS. NO PRODUCT IDENTIFIER/HEADER CHANGES
AND NO UNIVERSAL GENERIC CODE CHANGES ARE REQUIRED BY NWWS
CUSTOMERS... FOS CUSTOMERS...OR OTHER NWS CUSTOMERS. HOWEVER...
CUSTOMERS MAY WISH TO TAKE ADVANTAGE OF WATCH VALID TIMES AND
LATITUDE/ LONGITUDES OF WATCH BOX END POINTS FOR AUTOMATED
PLOTTING OF WATCHES. A GENERIC EXAMPLE OF THE CONVECTIVE WATCH
NARRATIVE/PRODUCT CATEGORY MKCSELX/WWUS9 KMKC FOLLOWS.
MKCSELX //X=0-9//
:XXX,YYYY XXX,YYYY XXX,YYYY XXX,YYYY: WWUS9 KMKC DDHHMM //XXX
IS LATITUDE AND YYYY IS LONGITUDE FOR EACH WATCH BOX END POINT//
MKC WW DDHHMM
STZ000-STZ000-ETC.-DDHHMM- //STANDARD ZONES UGC BY STATE WITH
TERMINATION DATE/TIME//
BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO /OR SEVERE THUNDERSTORM/ WATCH NUMBER XXXX
STORM PREDICTION CENTER NORMAN OK
LOCAL TIME/DAY/MON/YEAR
THE STORM PREDICTION CENTER HAS ISSUED A TORNADO /OR SEVERE
THUNDERSTORM/ WATCH FOR ALL OR PORTIONS OF
/APPROPRIATE STATE SUB-REGIONS/
AND ADJACENT COASTAL WATERS //IF NEEDED//
EFFECTIVE /DAY/ FROM /LOCAL TIME/ ... TO /LOCAL TIME/
//OPTION FOR ENHANCED WORDING TO DESCRIBE A PARTICULARLY
DANGEROUS SITUATION.// //OPTION FOR TORNADOES... - HAIL TO XX
INCHES IN DIAMETER AND THUNDERSTORM WIND GUSTS TO XX MPH ARE
POSSIBLE IN THESE AREAS. - //
THE TORNADO /OR SEVERE THUNDERSTORM/ WATCH IS ALONG AND XX
STATUTE MILES EITHER SIDE OF /OR NORTH AND SOUTH OF OR EAST AND
WEST OF/ A LINE FROM XX MILES //16-POINT COMPASS DIRECTION
SPELLED OUT// OF /LOCATION/ TO XX MILES //16-POINT COMPASS
DIRECTION SPELLED OUT// OF /LOCATION/.
REMEMBER...A TORNADO /OR SEVERE THUNDERSTORM/ WATCH MEANS
CONDITIONS ARE FAVORABLE FOR SEVERE THUNDERSTORMS /AND TORNADOES
/ //IF TORNADO WATCH// IN AND CLOSE TO THE WATCH AREA. PERSONS
IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER
CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS.
OTHER WATCH INFORMATION...//OPTION FOR - THIS WATCH REPLACES WW
NUMBER XXXX - OTHERWISE...NONE.//
DISCUSSION...//FREE PLAIN LANGUAGE TEXT TECHNICAL DISCUSSION OF
METEOROLOGICAL FACTORS NECESSITATING THE WATCH//
AVIATION.../TORNADOES AND/ A FEW SEVERE THUNDERSTORMS WITH
HAIL SURFACE AND ALOFT TO //SIZE IN INCHES// INCHES. EXTREME
TURBULENCE AND SURFACE WIND GUSTS TO XX KNOTS. A FEW
CUMULONIMBI WITH MAXIMUM TOPS TO XXX //HUNDREDS OF FEET// STORM
MOTION VECTOR XXXXX //VECTOR COMPONENT IN DEGREES AND KNOTS//.
...AUTHOR
:XXX,YYYY XXX,YYYY XXX,YYYY XXX,YYYY: //WHERE XXX IS LATITUDE AND
YYYY IS LONGITUDE FOR EACH WATCH BOX END POINT//.
.............END OF GENERIC EXAMPLE..................
IF YOU HAVE ADDITIONAL QUESTIONS OR CONCERNS...PLEASE CONTACT
WILLIAM ALEXANDER 301-713-0090 X115 PAUL JANISH 405-579-0719
E-MAIL WILLIAM.ALEXANDER@NOAA.GOV E-MAIL PAUL.JANISH@NOAA.GOV
OFFICE OF MEREOROLOGY W/OM11 STORM PREDICTION CENTER
1325 EAST-WEST HIGHWAY 1313 HALLEY CIRCLE
SILVER SPRING MD 20910 NORMAN OK 73069
APRS Documentation Series (Final Part)...
Here is the final part in the APRS Documentation series and this shows
how to interface a weather station to allow for APRS to be utilized
in APRS format via packet.
WX.txt 7.7 USING APRS IN WEATHER AND SKYWARN APPLICATIONS
New in 7.7: Added WX-DISP command to select the display format for WX
RAIN displays Time, Rain and Baro
WINDS displays Time, Wind and gusts and Baro
TEMPS displays Temps, Rain and Baro
CALLS displays normal callsign
OVERVIEW: APRS is an ideal tool for reporting weather conditions via
packet. It is compatible with both human entry as well as automatic
weather station entry of current conditions. With the optional $14 WX
registration, APRS will accept serial data from the PEET Bros ULTIMETER
or DAVIS home weather stations and automatically insert your wind,
temperature and optionally rain, humidity and barometric pressure into
your position/weather packet. You can even mount an ULTIMETER remotely
with only a TNC and Radio, and have it periodically report the remote
weather conditions. With these capabilities, APRS is idealy suited for
SKYWARN:
MAP DISPLAY - Shows the location of all reporting stations, their wind
speed and direction. Can also show the location of other objects,
such as reports of TStorms, Hail, Tornados, etc. You can also mark
large areas with either a rectangle, circle, triangle, or lines.
Use the OBJECTS-AREA symbol.
WEATHER ONLY - The JUST-WX command will cause only WX stations to be
shown on the map or P-List. Use the WX-JUST command to toggle
this feature on and off. The APRS NEXT command cycles through each WX
station in turn and displays its weather conditions in a box on top
of the screen. The location of the displayed station is highlighted
with a blue circle. Whenever a new report comes in from the
selected station, the weather window is automatically updated.
REPORT BROADCASTS - The individual station weather conditions can be
manually entered with the WX-ENTER command or automatically using
the optional APRS WX registration to enable the serial interface.
These reports are typically broadcast every 9 minutes. The report
is also available at anytime if an APRS user sends the WX station
an APRS Query, or the all-call WX query.
STORM/HURRICANE TRACKING - Any station may place a storm or other object
on his map, and it will be transmitted to all other stations. If
the object is given a course and speed of advance, then it will be
automatically dead-reckoned on all screens until the next update.
Any station can update the location of an object and will become the
new reporting station. This prevents duplicate reporting and
eliminates dependency on the original posting station. For Huricanes
and tropical storms/depressions a special COMMENT format will cause
APRS to color huricanes red, tropical storms yellow and depressions
blue. It will also show the radius of the winds with colored circles.
DDHHMM/LAT/LONG@CSE/SPD/TS/www^GGG/ppp>RRR&rrr
| | | | | * - - Radius of TS wnds
| | | | * - - - - Radius of HC wnds
| | | * - - - - - - Cenral Pressure
| | * - - - - - - - - Gusts
| * - - - - - - - - - - Sustained winds
* - - - - - - - - - - - - HC, TS, or TD
NOTE: APRS dead-reckons moving objects, so the symbol on the map is
presented where it SHOULD be, NOT where it was when first reported. To
hook one of these objects on the map, you must hook the little gray
circle which marks the position of the actual report, and not the symbol
itself. After two hours with no update, the symbol fades to dark gray.
NATIONAL WEATHER SERVICE DISPLAY - Suggested by KD4UYR in FLorida, this
feature parses NWS hourly bulletins (SA's) and plots the WX data on
the map. NWS sites now have a different symbol from home WX sites.
AUTO-HURICANE TRACKING - At the suggestion of KR4US I wrote NWSPARSE.bas
which will parse incoming NWS bulletins on one COM port, and output
APRS storm symbols and tracks via a TNC on the other COM port.
Using an old PC, this system can automatically inject WX storms
into APRS nets! It needs more work and additional parsing.
ON-MAP-WX DISPLAY - You may select to have the WX conditions displayed
by each WX station instead of the callsign. There are two formats.
One is activated by the WX-DISP-wx command shows the TIME, Barometric
Pressure, sustained wind and peak wind, The other is activated by
the WX-SHOW-TEMPS command. It substitutes Temperature for the TIME:
1420z976/36/45 Time,1420. Pressure 976. Wind 36 gusts 45
076'F876/36/45 Temperature of 76 degrees Faranheit
OPERATOR MESSAGES - The Point-to-point message capability can be used
for operator to operator messages and alerts.
COMMENTS - Transmitted along with each position report, there is a
short comment field which can be used to report weather conditions,
station status, intentions or other broadcast type information.
In addition to weather data included in position reports, the station
Beacon Text is also available for broadcasting additional amplifying info.
These beacons can be reviewed on the LATEST display. The APRS BULLETIN
feature is very powerful as an alerting mechanism to all stations on the
net. Even non-packet voice stations making a weather report can be placed
on the map (like an object) by another APRS packet operator. His station
will appear similar to any other APRS weather station, except that his
report will include a marker indicating that he was manually placed on
the map by another operator.
NATIONAL WEATHER SERVICE HOURLY BULLETINS
Based on work by KD4UYR in Clearwater FL, the SHOW-NWS-SITES command
searchs the NWSposns.DAT file and temporarily displays all NWS stations
within the boundaries of the current APRS map display (up to 250 miles).
Or if you want load NWS data at those sites, then you issue the LOAD-NWS-
SITES command to add these stations to your P-LIST.
The LOAD-WX-DATA command is used for loading a file of NWS hourly
reports. This file can be obtained from most of the commercial data
servers or some BBS's, or on the internet at wx.atmos.uiuc.edu. APRS
will scan the NWS bulletin file looking for each station that you have
on your APRS P-LIST. For each match, it will parse the Winds, temperature,
dew point and barometric pressure onto the P-list. It takes the remainder
of the report and places it in the L-list. The time of the entries in the
P and L-list will be the time of the NWS report (in local time). The date
is assumed to be the current date.
**** AS OF AUGUST 1996, The NWS REPORT FORMAT HAS CHANGED AND NO ONE HAS
**** SENT TO ME THE NEWEST REPORT FORMAT FOR ME TO UPDATE THE PROGRAM !***
Once the data is loaded, you can uplink selected stations to the APRS net
as desired. Be considerate, though, and not overload the channel.
Once everyone on the net sees the reports, the uplinking station should
consider Quitting the uplink in order to reduce QRM.
DEMONSTRATION: To see how APRS works in a SKYWARN or other reporting net,
load the backup file SKYWARN.BK using the FILES-LOAD command. To
demonstrate the NWS capability, center your map on FLorida at the 128
mile range enter the WX-GET_NWS_SITES command. Once all the NWS stations
appear on the map, then enter the WX-LOAD_WX_FILE command to load the
sample NWS data file provided by KD4UYR. Look at the P and L-lists to
see what is going on...
METRIC MEASUREMENTS: You may select wind speed in KPH and temperature in
Celsius by toggling the WX-METRIC command. This will force the WX display
at the top of the screen to display metric and will cause the manual WX
entry values to be accepted in Metric. You can make this permanent, by
saving a CONFIG file. The on-air APRS WX protocols, however, still
will be in MPH and F. Also, the ALARMS are compared to MPH and F values.
WX ALARMS: If a WX report comes in that exceeds your alarm values, the
station is plotted in RED and an ALARM sounds. The alarms are WIND, TEMP,
and RAIN. These settings can be used to warn of the passing of a warm or
a cold front. Use APRS and these alarms to make an almost un-attended
SKYWARN network! Install an APRS computer at the NWS site, and let the
NWS operators set the alarm levels. Then without transmitting a single
packet (there is rarely a licensed HAM on the premises) the APRS screen
will show SKYWARN data and where the alarm conditions are!
CLEARING ALARMS: When an alarm occurs, the station is drawn in RED and
the map is re-drawn to center on that station. Also, the station is
marked on the P-list with the ALARM marker. TO clear the alarm, simply
hook the station on the map, and then UNhook it (hit ENTER twice), or
use the WX-ALARMS-CLEAR command. To clear the A on the P-list, hook the
station and hit the A key. Normally, the ALARM on the P-list will only
sound if that station MOVES. Since a WX station should not move, there
is really no problem in leaving the A on the Plist until convenient to
remove it.
WEATHER WARNINGS AND WATCH BOXES: You can use the OBJ-AREA-LINE command
to draw a box plus-or-minus X miles from a line between points A and B.
The line and width are perfect for WATCH and WARNING boxes. If baseline
lengths longer than 400 miles are needed you must combine two or more
boxes. Use the normal OBJ-AREA-LINE command and indicate the +/- offset
of the sidelines in a 3 digit number of Miles enclosed in braces {075}
anywhere in the COMMENTS field.
HOME WEATHER STATION INTERFACE: With the optional $14 WX registration,
APRS inserts the ULTIMETER or DAVIS conditions in your position report
for unattended weather reporting. ULTIMETERS that output data with a *
output wind in MPH and those with a # in KPH. APRS detects the
difference and does the conversion. Also APRS averages the wind value
over the last 4 samples. Thats why the display UPDATE period is set to
15 seconds, so that the resulting wind speed transmitted represents a
1 minute average.
RAIN VALUES: In the Ultimeter-II, two rain count accumulators are
incremented every time the rain gage clicks (0.1 inch unless special
ordered for 0.01). APRS asks you which gage you have and converts both
to 0.01 inches on the air. Since the raw U-II rain values have no
meaning without knowing when they were last reset, APRS only transmits
the difference in rain for the last 60 minutes (/Rxxx) and the last 24
hours (/Pxxx). A reading of /R123 means 1.23 inches fell in the last
hour. After 60 minutes, this value will return to zero. A reading of
/P164 means 1.64 inches have fallen since the same hour yesterday. For
a REMOTE U-2000, this P value means rain since MIDNIGHT. Also since
there is no RAIN per hour value, that field is replaced with the /Cxxx
change in Barometric pressure. For a REMOTE U-II, the Raw rain count
is displayed as #nnnn and there is no P value. There are four possible
formats for an ULTIMETER depending on whether it is local or remote:
.../LAT/LONG_CSE/SPD/Txxx/Rxxx/Pxxx/U-IIauto Original U-II w APRS
CSE/SPD/Txxx#xxxx/P.../U-IIrmte Original U-II remote
CSE/SPD/Txxx/Rxxx/Pxxx/Bxxx/Hxxx/dvs Davis WX station
CSE/SPD/Txxx/Rxxx/Pxxx/Bxxx/Hxxx/U2k U-2000 with APRS
CSE/SPD/Txxx/Cxxx/Pxxx/Bxxx/Hxxx/U2r U-2000 remote
R... B.../H... devices not connected
New in version 7.7, the / separators are omitted and lower case letters
serve as delimiters and format identifiers.
With the WX interface enabled, the normal APRS decaying of position/wx
reports still holds as long as nothing changes (except the wind). This
way, redundant WX reports do not cloud the channel. If any value,
Position, temperature, rain, barometric pressure, or comments change,
then the periodicity is reset to the value set in the alt-SETUP-POSrate
command. Since the wind is the most changing parameter, the WX-WIND
command can be used to set a Wind threshold. Whenever the wind is above
that threshold, the reporting period is also reset to the POSrate value.
Nominally, you might want to set the POSrate value to about 4 minutes or
so. This way, during changing WX conditions, or wind above your
threshold, the WX is reported every 4 minutes. Otherwise, the period
rapidly decays back to the maximum APRS delay period (default is 20
minutes). For a weather station, you might want to change this MaxPeriod
to maybe 10 minutes or so. Use a text editor to change this value in
your CFIGxxx.APR file. There it is expressed in seconds. Of course, a
WX/position report will be transmitted by the APRS station at anytime,
in response to an APRS or WX query.
ULTIMETER INTERFACE CABLE: Peet Bros sells an interface cable with a
DB-25 connector to RJ-11. (Note, this is a DB-25, not a DB-9). Since
the U-II has no negative supply, a 5 K pulldown resistor is added to the
DB-25 connector between Pins 2 and 3. This uses the -5 or -12 volts on
your TXD line to bias the RXD line. When I plugged in a standard phone
line connector to the U-II serial data output (unmarked connector on
their junction box, or side of the Display unit), I found the data output
on the green while using the black wire as ground. If your connector was
crimped on backwards, red is data and yellow is ground. The Peet Bros
cable includes transient protection and RF filtering to protect your
computer as well as providing the bias resistor. Remember, the
annemometer is like an antenna, high in the air. It can radiate RFI and
take lightening charges... The U-2000 is directly RS-232 and needs no
pull down resistor.
DAVIS INTERFACE: You must have the DAVIS Weather Link serial interface
option before your Davis station will output serial data. Simply connect
their connector to your PC. You MUST use the APRS alt-SETUP-OTHER-AGL
command to set your average ground level. This converts your baramoter
readings to their equivalent value at sea level... Experiment with your
exact AGL until your BARO readings match the readings on your instrument
or local NWS.
SAVE A COMM PORT! You can use a simple 89 cent switch to allow other
devices to share a single COMM port with your WX station. Since the WX
stations only use ONE pin and GROUND, simply add them to your MODEM
cable with a simple SPDT switch as follows:
ULTIMETER-II >---------*--------* sw1
| <----*--------------> RXD
MODEM } >------------------*
or } |
other } *-----/\/\/\/\-------*
serial } 5.6k |
device } <------------------------------*-------< TXD
} * * * -----------------------------* * * other pins
} *--------------------------------------* GND
Actually, you can wire this to any serial device that you do NOT use while
running APRS. I chose my MODEM that is on COM2. Note the series resistor
as mentioned in the text to provide the -V pull-down for the U-II output.
REMOTE ULTIMETER OPERATION: There are two ways to build a remote WX
reporting station with only a ULTIMETER, TNC and RADIO. This uses the
GPS features in most TNCs to do the timing for periodically transmiting
a WX report. Here's how:
For the U-II and 2000: Program the TNC GPStext parameter to recognize
the * or # character for the U-II or the !! for the 2000, instead of the
usual $GPS formats. Then set the timing for each transmission to be about
once every 5 minutes. Be sure to SET ECHO off! This is because the
ULTIMETER-II uses a 10k resistor on the TXD line to bias the RXD line.
If the TNC is echoing the U-II data, then total garbage results!
(KD4GOE figured that one out!).
U-500 and RECENT TNC: Do NOT program the GPS functions, but put the
U-500 into packet mode and put the TNC in "UIMODE", or PMode-CONV or
whatever command sets the TNC to power up in UNPROTO CONVERSE. Once
every 5 minutes, the U-500 will generate a packet. You must set
LFIgnore to ON. Since the Kantronics TNC's do not have LFIGNORE,
you must set SENDPAC to $10 (linefeed) and set CR off! If there are
dozens of REMOTE U-500's, hopefully their clocks are staggered enough
that they wont all transmit at EXACTLY the same time.
WX POSITION: In both cases, you must put the unit's POSIT in the BText
using the "_" WX symbol. What is transmitted by the TNC then is a BText
WX posit with no WX data, and raw WX data with no posit! APRS cannot
display the WX on the map until it has received a WX posit beacon. So,
set the beacon to go about once every 10 minutes. Since the remote site
can also be a WIDE-RELAY digipeater, it should show the WX circle symbol,
but it will be GREEN to indicate it is also running with the ALIASes of
WIDE and RELAY. (assuming you have the words WIDE-RELAY in the BText
posit. This will not happen until a POSIT beacon comes in AFTER
a WX report.
DATA LOGGING: The POSITION FILTER normally causes APRS to NOT save
duplicate position reports that are within 80 yards of a previous report.
If you toggle this filter OFF, it reduces this filter range to 20 yards
AND enables all WXstation logging. In this mode, all WEATHER station
reports are saved in a track history file. All over-the-air reports are
only received once every 10 minutes, but your own report will be saved at
the rate set by the Set-Pos-Rate command.
AUTOWX.EXE: This is a program written by Les, N5KOA to also interface
the Ultimeter to a TNC with a PC. It allows direct connections for WX info,
it does WX beacons in APRS format, and allows continuous logging of WX
data to a binary file just like the Ultimeter ULTIITSR program. I have
not used nor tried this program. Do not send disks, but about $5.00 to
cover disk & postage to:
Les Blalock, N5KOA, 1711 Pagewood, Odessa, TX 79761
(915) 332-7112 day, 332-1942 fax, 367-0408 eve
Packet: N5KOA @ N5RKN.#WTX (Odessa, TX).
Internet n5koa@basinlink.com
FINAL NOTES: Since the WXstation option is always updating your outgoing
position report, this makes it impossible for a WX station to report a beam
heading during a Direction Finding evolution. If you use the BEAMHEADING
command to enter a beam heading on a Fox or Jammer, then your WX station
is disabled. To restore your WX station, restart the program.
$$$ The ULTIMETER-II is available from PEET Bros 1-800-USA-PEET
(872-7338) for $199 plus $20 for their Serial interface cable and
$68 for the optional rain guage (self emptying, 0.1 inches) plus
shipping of $8.75. (For APRS, their $69 software is not required
but it is a good package for doing the usual home WX logging and
analysis) See ads in QST, CQ, Popular Mechanics, etc.
The ULTIMETER-2000 is also available for $379 and includes
Barometric pressure. Outside Humidity/Temp sensor is $110.
The higher sensitivity .01 rain gauge is $90. And a wireless
remote rain gauge is $139.
The ULTIMETER-500 $239. is the same as the U-2000 but without the
barometer and humidity.
The DAVIS Weather Monitor II is available for about $395. Rain
gage is $75, and outdoor Humidity/Temp sensor is $125. For APRS
you will also need their WeatherLink for $165.
That concludes this week's edition of the SKYWARN Newsletter,
Comments, Questions, or Suggestions are always welcome. The next
SKYWARN Newsletter will be issued in the February 23rd-24th timeframe.
Respectfully Submitted,
Robert Macedo (KD1CY)
ARES SKYWARN Coordinator
Greater New Bedford ARES Emergency Coordinator
Home Phone #: (508) 994-1875
Home/Data #: (508) 997-4503
Work Phone #: (508) 435-1000 Ext.: 3411
Email Address: rmacedo@ma.ultranet.com
Packet Address: KD1CY @ AA1FS
http://www.ultranet.com/~rmacedo
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