Transmitting science from Jool

[RealKerbal3x]

So recently I've been designing a probe mission to Jool that will deposit tiny landers on each of its moons, as well as send a probe plunging into the gas planet itself. But I'm worried about the landers' electric charge - will 900 EC be enough to transmit a single science report through the Communotron 88-88 antenna? They have solar panels so they should be able to recharge but I'm not sure if they have enough for a whole report in one go.

Edited October 13, 2020 by RealKerbal3x

[Superfluous J]

3 hours ago, VoidSquid said:

Kind of: it will transmit until the EC is used up, then stop until sufficient EC is there for the next data package, transmit that, and so on. 

While the warning when enabling partial says that you actually might lose a bit science this way, I never found that to be true (or I might not have looked too closely, lol).

No it does lose science. I wish it didn't because it makes no sense but it does. It's similar to how you gain less reputation when you have a lot of reputation. Except Science is useful.

Basically if you already have 0% of something and transmit 50% of it, you get credit for the 50%. If you already have 50% and transmit 50% you get something like 50% of 50%, or 25%. So if you transmit it all in one go, you get 100%. if you transmit it in 2 packets you get 75%.

Those numbers aren't accurate. They're simplified to make the point. But the concept is there.

Edited October 14, 2020 by Superfluous J

[Vanamonde]

The amount of data transmitted is the same regardless of where the test is run. So put batteries and instruments on a test build and try it on the launch pad. Be aware that recharging the batteries is much slower way out in Jool, space, though. But it's easy enough to cheat a ship out there for testing purposes, too. 

[VoidSquid]

1 hour ago, RealKerbal3x said:

in one go.

You can set the antenna to "transmit partial".

[VoidSquid]

1 hour ago, RealKerbal3x said:

Thanks for the tip, so will that automatically resume transmission once the craft has sufficient electric charge?

Kind of: it will transmit until the EC is used up, then stop until sufficient EC is there for the next data package, transmit that, and so on. 

While the warning when enabling partial says that you actually might lose a bit science this way, I never found that to be true (or I might not have looked too closely, lol).

[king of nowhere]

900 is enough for most purposes. I'm not sure it can transmit a full scanner report, and it defeinitely won't be able to transmit all the science from a full science lab. aside from those corner cases, it will be enough for everything else.

be careful to time your jool plunge to a moment when you actually have contact with kerbin

[RealKerbal3x]

12 minutes ago, king of nowhere said:

900 is enough for most purposes. I'm not sure it can transmit a full scanner report, and it defeinitely won't be able to transmit all the science from a full science lab. aside from those corner cases, it will be enough for everything else.

I'm only going to be transmitting the rerunnable science experiments (barometer, thermometer, gravioli detector, seismometer etc) so I hope it'll be fine. The probes that will be landing on moons will have all the time in the world to recharge their batteries after transmitting, but I'm not sure the Jool entry probe will have enough time to transmit all of its science before it gets crushed.

Edited October 13, 2020 by RealKerbal3x

[RealKerbal3x]

10 minutes ago, VoidSquid said:

You can set the antenna to "transmit partial".

Thanks for the tip, so will that automatically resume transmission once the craft has sufficient electric charge?

[Grogs]

1 hour ago, RealKerbal3x said:

I'm only going to be transmitting the rerunnable science experiments (barometer, thermometer, gravioli detector, seismometer etc) so I hope it'll be fine. The probes that will be landing on moons will have all the time in the world to recharge their batteries after transmitting, but I'm not sure the Jool entry probe will have enough time to transmit all of its science before it gets crushed.

If you look at the big table about halfway down the page below, it has the EC cost to transmit the various experiments. If you're doing an atmosphere scan of Jool, that's 2000. The next most expensive is the gravity scan at 600. I agree you probably won't have enough time to recharge a probe entering Jool's atmosphere, so I would pack enough battery to transmit everything in one go onto that one.

https://wiki.kerbalspaceprogram.com/wiki/Science

[VoidSquid]

Interesting... unfortunately I don't have a career save game at hand right now to test this.

I won't think the "transmitting partial punishment" is that bad though.

[s_gamer101]

You can test this on the launchpad, I always do that when I‘m not sure if I have enought. Just „launch“, run your experiments, transmit them back and revert the „flight“

[VoidSquid]

Thing is, the tech tree is complete, and I've gone for 100% patent licensing. And there are almost no experiments left to conduct at Kerbin, Mun, Minmus.

I might see if I find a very old save game to test, hopefully not resulting in a mess with all the mods changed in the mean time.

Or maybe start a science career, just for purpose of testing.

Edited October 14, 2020 by VoidSquid

[VoidSquid]

@Superfluous J @RealKerbal3x

Quick and "dirty" test done: from 32 science, I got 21.88 doing partial w/ no initial stored EC = 68%

As the solar panels do continuous charging (I removed all EC using Hyper Edit, but I can click only so fast), I'd think it's just two thirds.

So: I stand (actually sit) corrected, the penalty IS hefty.

Edited October 14, 2020 by VoidSquid

[s_gamer101]

12 hours ago, Vanamonde said:

Be aware that recharging the batteries is much slower way out in Jool, space, though.

As long as you use solar panels

[RealKerbal3x]

19 hours ago, s_gamer101 said:

As long as you use solar panels

Sadly for tiny probes, solar panels are really the best option. RTGs are too heavy (and expensive to boot) and fuel cells require a supply of LFO. I'm going to have to pack a lot of batteries and deal with the long charging times.

[Kerbal Productions]

You might get worried for that. So bring at least 2 communicator and 2 solar panels. That might help.

[jimmymcgoochie]

If you’re transmitting from Jool, put the most power-efficient antenna you can on the probes themselves (even if that’s a Communotron 16) and trickle the data out slowly, then bring a hefty relay on the main ship to bounce the signals back to Kerbin.

Solar power at Jool is around 4% of what you get at Kerbin so even a Gigantor solar panel produces just 1EC/s and the probe-sized panels are barely worth having; RTGs are expensive, but they deliver a lot more power for their weight than solar panels when you go out that far and a slow transmission rate gives more time for the batteries to charge up during the transmission. If you’re planning to throw a probe into Jool and want it to continuously transmit science, RTGs and a static antenna (16-S or possibly RA-2, though relays are power inefficient and slow) are your best bet as anything deployable risks being torn off by airflow.

Gravity and seismic scans are the two experiments you need to watch out for wherever you go as they require a lot of data to be transmitted. Atmosphere analysis is even bigger, but only applies when you’re in an atmosphere and only Jool and Laythe have those.