I’m working on my senior design project. It’s basically a tethered helium balloon that will carry a wireless weather station to record weather data at different elevations [between 230-300 feet no more] for various applications.
So I am interested in getting something off the shelf, rather building it up. All I need is a Hygrometer and a wind sensor, they will be carried/fixed to a gondola. There are two major factor affecting the purchase decision: 1. Cost 2. Components Weight (most)
I’ve been looking around, and it looks like the La Crosse WS2308 is a good choice because it’s wireless,affordable ($180 inclusive), but there is no information available about it’s components weight.
I would highly appreciated if anyone could answer some of these questions:
Should I go for it? Will it work smoothly for such task?
Is there another alternative out there that is under $120-150 USD (excluding shipping) 3. Do you have any idea of how much will the Hygrometer and Wind sensor weight? Or could someone possibly measure theirs :D, this is very important for lift calculations.
HoneyWell TE923W vs. LC WS2308 ?
Is there a kit out there with live wireless data streaming directly to a PC?
Any other thoughts/ideas/offers are welcomed.
Sorry for posting too much questions for a first post…
How high will this balloon go? The WS-23xx is only probably effective to about 100-150 feet OUTDOORS. I found that I had reception problems with as little as 25 feet indoors.
I think the WS-23xx may bearly work at that height. I think LaCrosse massively over exaggerates the range (Don’t say I didn’t warn you
Not that I’m aware of…
No idea… you also need to add the weight of cabling and the weight of the transmitter unit. You could probably shave some weight with a dremmel though and shortening the cabling
They’re pretty much the same, as far as I know.
You need the base station to hook to the computer. It comes with the base station.
If budget is the primary concern, you’ll have to work with the LaCrosse. I can’t think of any other for the cost.
But isn’t the Hygrometer unit is the transmitter as well?
6) If budget is the primary concern, you'll have to work with the LaCrosse. I can't think of any other for the cost.
Ok,lets say that money is not an issue,what would be the next level?
Even if you drop down the wireless option, a data logger (like HOBO) still costs more than LC!
Anyways, thanks for your quick reply, some useful information.
Niko I can see that wireless would be a nice option when going 250 - 300 feet in the air however if the balloon is tethered then wired would be an option HOWEVER the maximum wire transmit for a La Crosse is 150 feet, maybe 200 if you got lucky so that would rule that out yet again…
The Hygrometer unit is the transmitter as well Solar_Racer. The wind sensor would have to be wired to the Hygrometer unit which transmits the Temp, Humidity and wind. However note that the La Crosse Hygrometer unit is horrible unless properly shielded and in full sunlight aloft the temp readings would be very suspect…
The Wireless option is best because a cable will add significant weight and cannot run for the required elevation range. Maybe I’ll go with a logger, instead of a wireless kit since it looks like everyone is not enthusiastic about LC
The balloon will have a 6.2 ft of inflated diameter, which will give me a gross lift of 3.95 kg , the balloon itself weights 0.8 kg, so my payload (gondola assembly,tether lines,picavet and weather kit should not be more than 2.15 kg , so 3.95 - (0.8+2.15) = 1 kg of Free lift, that will make the balloon go up on its own.
The problem with Oregon Scientific WMR 968 is that the solar cells make it heavy. Check out the manual-(Small PDF file), the combined weight of the Hygro/Wind sensor/solar cells is : 1.1 kg! Which will leave little space for other components, besides fixing the solar cells to the gondola and yet be exposed to sunlight will be a tricky job.
Unless someone has tried running the OS WMR 968 on batteries only, I would consider it.
Wow, so is the LC really that bad? Or most complaints are about accuracy and abrupt data streaming?
What particular Wx/atmospheric parameters are you trying to measure as that will make a big difference to the platform weight?
I suspect really the parameters that matter are temp/humidity and maybe windspeed, as the other components are likely to be the same at ground level. Thus I would think that a WS2300 series using the Hygro/Tx unit may be ideal although maybe a little limited in Tx range capability if used full air to ground mode. If the Console were to get airborne too, that might help matters as it will record the data for 176(?) data sets. The hygro/tx has very low weight (including the 2 x AA batteries) and has the possibility of using the anemometer windspeed without direction vane as that would be ultra difficult to keep orientated correctly. I’ve just weighed the console and it weighs 14.25 oz including batteries. The hygro/tx unit must weigh considerable less.
Added: The Hygro/Tx unit weighs 7 oz (inc batteries)
You could use the Oregon WMR INDOOR Baro / Thermo / Hygrometer. It weighs including batteries approx 100gm. It is not recomended for outside use obviously but I have used one outside in a sheltered spot for 2 years with no problems. For the anenometer you would have to use the solar/battery transmitter as it is all one unit but I have just weighed the transmitter and it is under 400gm with batteries. The anenometer I have just weighed, and it is under 400gm, but it could be reduced by losing the mounting u bolts and using screws. These weights are not guaranteed - check them carefully yourself.
Bob
As the WS2300 console measures temp/humidity and pressure, I would put the console alone in a well-sealed polly bag and just get that aloft. If you need anything else recorded it all adds significantly to the weight package.
Added: An Inspeed Vortex anemometer, with the cable to the PC being partially used as a tether component, may not be too heavy, even at the lengths you are considering.
You’ve guessed right,it’s Temp,RH,and windspeed, any other parameters would be great, but they count as extra.
I've just weighed the console and it weighs 14.25 oz including batteries. The hygro/tx unit must weigh considerable less. Added: The Hygro/Tx unit weighs 7 oz (inc batteries)
You are the best! Thank you very much.
The wind sensor looks like it gonna be 16oz, but taking out the direction sensor,extra cables or mounting arm, we could reduce weight considerably I think.
THanks a lot for doing that, how nice of you. But I’m not sure if the indoor unit has a wireless transmitter or even a data logger, so I’m not sure if it would actually work.
The problem is, that the cable itself should be able to maintains certain tension forces at given altitudes and wind speeds. Besides, the cable would add more weight, and create extra hassle.
I think I gonna go for the WS2308, but remove the wind direction thing and make the console aloft if it doesn’t work at first trial!
Though getting data logger in this case would make much sense! The HOBO set costs more than a wireless LC!
If you use one of the LaCrosse units with a propeller type wind sensor, which I think applies to all the 23xx series, you have to include the direction vane, because the direction vane rotates the propeller mechanism so that it is facing the wind.
You could eliminate the weathervane portion only if you are using a cup type anemometer
Whoa! You are a life saver! You are absolutely right about that.
So in this case maybe the HoneyWell TE923W would be better…Now I was wondering if any of these kits measures the Air pressure, they mention Barometric pressure, from what I could understand that they gives the pressure relative to the temperature and RH measured? Is that correct?
The T/H for the TE923 is 2.29 oz (65g) [Without batteries]
Anemometer is 11.12 oz (315g) [without batt.] and the wind vane could be removed, though here is the catch : The Max. transmission range of the anemometer is 100 feet (30 m) only.
I guess it’s La Crosse for now, unless someone could come up with a very good reason not, or an alternative, like another wireless kit or an affordable data logger combo.