Sonde Radiosonde Decoder (PC & Mac)

iMONITOR

Silent Key
Premium Subscriber
Joined
Sep 20, 2006
Messages
11,156
Location
S.E. Michigan
Sonde Radiosonde Decoder (PC & Mac) Free to try
Decode radio transmissions from radiosondes (weather balloons)

 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,109
In U.S.
400-406 MHz (channels depend on the models) and
1676-1682 MHz, being phased out in U.S. to all 403 (400-406 MHz)
 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,109

The regular twice daily (around 0000 UTC and 1200 UTC) launches in my are LMS6 from two sites and DFM17 form one site (that switched recently from LMS6). Only experiment activities on occasion in my area seem to be RS41--in the U.S. relatively few RS41 launches in comparison . I am expecting more LMS6's to be replaced by DFM17. I have recovered LMS6 and LFM17 but had to buy an RS41 off eBay to actually get my hands on one of them.
 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,109
The regular twice daily (around 0000 UTC and 1200 UTC) launches in my are LMS6 from two sites and DFM17 form one site (that switched recently from LMS6). Only experiment activities on occasion in my area seem to be RS41--in the U.S. relatively few RS41 launches in comparison . I am expecting more LMS6's to be replaced by DFM17. I have recovered LMS6 and LFM17 but had to buy an RS41 off eBay to actually get my hands on one of them.
In the above, "LFM17" should have been "DFM17"
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
8,944
Location
Stockholm, Sweden
The regular twice daily (around 0000 UTC and 1200 UTC) launches
They seem to release a lot more balloons in me area at other times of the day. I heard two today between 9 and 12 UTC and often some in the evening as well. They are short lived. I think it's just 1-2 hours before they burst at high altitudes at about 20.000 meters, 60.000ft as they climb at a 3-5m/s rate and then fall almost at a 50m/s speed, 100mph. When the conditions are right it's possible to monitor balloons over other countries.

/Ubbe
 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,109
They seem to release a lot more balloons in me area at other times of the day. I heard two today between 9 and 12 UTC and often some in the evening as well. They are short lived. I think it's just 1-2 hours before they burst at high altitudes at about 20.000 meters, 60.000ft as they climb at a 3-5m/s rate and then fall almost at a 50m/s speed, 100mph. When the conditions are right it's possible to monitor balloons over other countries.
/Ubbe

They are much slower near the ground when the parachute deploys--not fast at all and often get stuck in a tree. Also, I have tracked many (hundreds) balloons here and all I have seen got to about 35,000 m (over 100,000 ft) . We must have better balloons here.

alt_ex.jpg
 
Last edited by a moderator:

Ubbe

Member
Joined
Sep 8, 2006
Messages
8,944
Location
Stockholm, Sweden
all I have seen got to about 35,000 m (over 100,000 ft) . We must have better balloons here.
It could be that they are deployed for different purposes. The cheaper rubber they use here, and they have no parachutes and the RS41 weigh only 100 grams, are probably sufficient to do a 20.000 meter level to predict the weather at ground level. Going higher you will probably do other types of additional measurements above the troposphere into the stratosphere.

/Ubbe
 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,109
It could be that they are deployed for different purposes. The cheaper rubber they use here, and they have no parachutes and the RS41 weigh only 100 grams, are probably sufficient to do a 20.000 meter level to predict the weather at ground level. Going higher you will probably do other types of additional measurements above the troposphere into the stratosphere.

/Ubbe

Are yours actually rubber or are they latex like ours? Attached is a DFM-17 photo where one can see what is left of the exploded balloon, the parachute, the radiosonde, and string un-winder user a launch.

DFM-17 .jpg
 

N7ZDX

Member
Joined
Oct 22, 2021
Messages
6
Just saw this thread. I've been tracking and recovering the WX balloons out of Salt Lake City, Utah, Elko, Nevada, and Boise, Idaho for the past few years as a fun and challenging hobby and to get me out of the house. I was starting to receive a lot of inquires on my personal Facebook page about it so I started a Facebook group titled No Weather Balloon Left Behind - North America Radiosonde Chase Group. The purpose of the group is to share experiences and offer information on how and where to track the balloons. Anyone interested is welcome.

Also, I've been using Sonde for decoding LMS6 (403 & 1680) and I find it more reliable for decoding than SondeMonitor. Unfortunately the developer isn't interested in adding an NEMA GPS output for mapping, and last I checked, DFM-17 isn't an option. Still hoping he adds it.

Auto_RX is a feature-rich system with live prediction of landing area based on realtime balloon trajectory and will decode DFM-17, but requires a Raspberry Pi and knowledge of Linux. I'm getting ready to setup an Auto_RX station in Southwest Idaho so we'll see how that that goes. Cheers everyone.
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
8,944
Location
Stockholm, Sweden
Are yours actually rubber or are they latex like ours?
It's probably rubber to keep them at lower altitudes. I tracked one yesterday at 10UTC that burst at 16000 meters. I've only found one balloon myself when I was a kid and it was the same rubber as in party balloons and I've seen pictures of crashed balloons of today and it seems to be the same rubber and no parachutes but often has a radar reflector.

/Ubbe
 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,109
It's probably rubber to keep them at lower altitudes. I tracked one yesterday at 10UTC that burst at 16000 meters. I've only found one balloon myself when I was a kid and it was the same rubber as in party balloons and I've seen pictures of crashed balloons of today and it seems to be the same rubber and no parachutes but often has a radar reflector.

/Ubbe

All latex and no radar reflectors but with parachutes and small parts of the latex balloon on the 10 that I have I have recovered.
 

shajoe44

Member
Joined
Dec 11, 2000
Messages
488
Location
North Augusta, SC
How can you find out what States and Cities they are launched from? I live on the SC-GA border near Augusta. I would love to tinker with this. I already have 2 airspy dongles I use for DSDPlus activities. Thanks
 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,109
How can you find out what States and Cities they are launched from? I live on the SC-GA border near Augusta. I would love to tinker with this. I already have 2 airspy dongles I use for DSDPlus activities. Thanks

In your case, the nearest launches are from Altlanta, Charleston, and Jacksonville. My (possibly outdated) information says the first two are 1680 MHz LMS6 (actual frequency can be 1676, 1678, 1680, or 1682 MHz), the recent launch from Charleston was on 1676 MHz, reperted as 1676.06 MHz, while Jacksonville is an RS92-NGP using same frequencies so your AirSpy will not do. Note where there are more airports, there will be more launch sites. I do not know which channels they are using as no one down there seems to watch. Note I have been told many site will switch to "403" (actually channels in the 400-406 MHz range) MHz in the future. I see no "403" MHz ones anywhere near you but there may be university research ones on ocassion. Worldwide, standard observation times (for then non-research ones) are 0000 and 1200 GMT. In my case, I see launches from 3 NWS offices but also from 2 universities at times (all mine are "403" MHz) and I use an AirSpy for them. I have 10 of them sitting on the floor in this room (7 from NWS and 3 from a university) but a good number end up "permanently" stuck in high trees in this part of the country. The research ones from universities are hard to know when/where and even when I contacted one to inquire after recovering one, their office said "must be one of our grad students but do not know who".
Usually you will see them move easterly but they go about 3 times as high as a commercial jet and reception of up to 100 miles is often possible.
See
 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,109
So what do you do with them after you recover them??

For ones for test purposes, lower the power and replace the antenna with a dummy load. For some, I keep one intact and one opened up as my own little "museum" of each model. I go after them as mostly an exercise of skills and physical exercise (my area has a lot of woods, hills, and fields). Also an exercise in diplomacy of speaking to the land owner. I know some are working on how to turn some models into APRS weather but have not seen any success. When retired, one has time to do such things.
 
Top