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Comment by semi-extrinsic | Hacker News Reader

I'm pretty sure this was a typo, so s/radar/weather/ .

For reference, a weather radar operates in Doppler mode with return signal coming from Rayleigh scattering of raindrops, so it's on the 3cm - 10cm wavelength. You are talking about something like a 5 meter diameter antenna dish that weighs half a tonne, which is on an elevation-azimuth motorized mount, in a 7 meter diameter radome, with peak transmit power of 250 000 W.

Of course you can buy one yourself, if you have the space, electrical power and money for it - ballpark 1.5 mill. USD.

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I've worked on a weather radar system with specs suspiciously similar to those you are describing. 250kW is a pulse power for a C-band stationary radar system, with a typical pulse length around 1us repeated 500-1000 times a second it amounts to 1/1000 duty cycle and 250W average radiated power. These pulsing parameters give about 150-300km of usable range, return signal becomes too noisy on longer ranges anyway and geometry of beam propagation means that you're shooting into outer space above meteorologically interesting part of atmosphere. It doesn't use that much power from the grid either - datasheet specs around 5kW total for all the stuff (transmitter, motorized antenna pedestal and equipment rack with a pretty beefy server to chew all that data coming from the receiver in real time). The cost aspect is pretty much in the ballpark - I've once visited our test site and the engineer pointed on the antenna horn (about paint can sized chunk of metal hanging in front of the dish full of microwave RF magic ) and told that just that piece costs about the same as a new high-segment car.

C-band weather radars existed since forever, first using magnetron transmitters and now solid-state amplifiers, though there are still a lot of new magnetron-based systems being installed, with the downside that magnetron pulses are practically impossible to modulate to perform advanced radar techniques that improve different aspects performance. There are also X-band weather radars, which operate on higher frequencies and use more modestly sized antennas (but still larger than you'd like to have on your house roof). They are more limited in range (100km-ish max) due to high attenuation and mostly used at airports, offshore oil rigs and windfarms and similar installations that mostly interested in precise local weather. They are still several hundred thousand bucks.

I don't know how much this costs, but it's only a meter, 65 kg, and runs on a 110 volt outlet. I'm thinking high ones of thousands of dollars, maybe low tens of thousands.

https://www.furuno.com/files/Brochure/448/upload/WR110_EN.pd...

They only list agents and the agents don't list prices and few feature the doppler weather radar on ther website ..

That said, I'd guess $10,000 US < price < $50,000 US for that product given the pricing of $8K US for smaller commercial fishing radars from the same company.

More on the two compact weather radar systems: https://www.furuno.com/en/systems/meteorological-monitoring/

Probably another order of magnitude more expensive.

Maybe, maybe not.

There's another recent peer comment that confirms 1.5 million US for a large 250kW is a pulse power for a C-band stationary radar system with 300 km of range.

This is a small doppler with modest power and 70 km range max.

If cost is proportional to the 3D volume of space scanned (as the power requirements likely are) Then this small mini radar might well be less than 100K.

TBH I have no specific knowledge here although I have worked in other sensing domains and seen a wide spread on cost of equipment related to volume and quality of data.

I'd be interested in the flat cost price of the mini system, I suspect that's not going to appear without some inside knowledge or working a dealer, it appears to be a rare bespoke kinf of thing, not like the commercial fishing radars.

Ballpark, 80k to 150k for those Furuno systems in the USA depending on single or dual polarity, etc. I have taken the sales pitch.

Thanks for that, interesting and not unsuprising after factoring in commissions + profit.

Even if you buy one you will almost certainly need to get spectrum approval to transmit, which is non-trivial and comes with many strings.

https://www.meteopress.cz/meteopress-com/ These guys started to produce beefy radars order of magnitude cheaper

I plan on installing one of these at my apartment building so that my tenants can have their own local weather channel.

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