Antenna questions

[MetricKerbalist]

Hi KSP colleagues,

I am flying my KerbolX spacecraft around Kerbin.  I have attached two HG-5 High Gain antennas.  When I right-click on them, several items appear, and I would please like to understand these:

• Retract or extend antenna.  OK, that's obvious.
• Require Complete, or Allow Partial.  What is that, if I may ask?
• Antenna Rating: 5.00M (Combinable).  First, minor note about notation.  That should read 5.00 m.  But what does "combinable" mean.
• Transmit data and Stop transmitting.  This could lead to a while big thing.  I'll ask the question nevertheless if I may.  Isn't the spacecraft always transmitting data?

That's it.

Thank you for your consideration.

Stanley

[modus]

- obvious indeed

- the required complete has to do with transmitting science. Quoting from elsewhere in the forums: 'Require Complete' is the standard and the most reliable. Once you start transmitting it will consume the necessary power until the transmission is completed. If you run out of power before completion the transmission will fail. The science will be stored but the electricity is lost. Once you have restored your power you can try again.  Allow Partial' can be buggy but will allow you to transmit large packets even with small batteries. When 'Allow Partial' is used the transmission starts as normal but when you run out of power the transmission is paused until you have generated enough power to resume. However this will keep your power levels between zero and almost nothing leaving you with a pretty much dead craft until the transmission is completed.

- the M is not meters, but antenna strenght. For more about this, and about 'combinable',  please see https://wiki.kerbalspaceprogram.com/wiki/CommNet

- you transmit data when you transmit science. You are -hopefully- always in connection, but not always transmitting data.

 

[MetricKerbalist]

13 minutes ago, modus said:

- the M is not meters, but antenna strenght. For more about this, and about 'combinable',  please see https://wiki.kerbalspaceprogram.com/wiki/CommNet

Hi @modus,

Good.  Let me study the KSP wiki page about CommNet.  I was hoping to be led into some avenue that would explain this in some detail.

Thank you.

Stanley

[bewing]

The 'M' is not meters, it is an abbreviation for MILLIONS.

 

Edited June 27, 2021 by bewing

[MetricKerbalist]

Thank you, @bewing.

[jimmymcgoochie]

Antenna strength is measured in metres, mostly in multiples of metres- the earliest antenna can reach just 500km, but the biggest and best can manage 100Gm. You can use more than one antenna to boost your range, however they don’t add up linearly- each additional antenna only adds a certain percentage of its maximum range (I think it’s 75%) and this effect gets more pronounced with every additional antenna (so two 5M dishes together would only have a range of 8.75M, and adding a third would take that to about 11.56M. Diminishing returns can be pretty severe when using many smaller antennae so use a smaller number of more powerful antenna whenever possible.

Here’s a handy guide for antenna ranges relative to the stock solar system:

There are also some mods that can help calculate antenna ranges while in the VAB/SPH so you’ll know if you can communicate back home.

Transmitting data refers specifically to sending back science experiment data. This can be done in two ways- require complete does exactly that, and will abort the transmission if you run out of power, but allow partial will transmit what it can as soon as it has the power to send it. Partial transmissions can be useful when you have (lack of) power generation or storage issues as it allows you to send some data, but a partial transmission doesn’t get the full science reward for that experiment so you’ll need to do it again to get the full credit.