WRXB215

Capacitive coupling is only for the AC of RF. Capacitors block DC. No DC ground for your antenna is needed. 
However, poor electrical connections between body parts can be a cause of noise so people frequently bond body parts together with copper braids. 

I was told figuring out the FCCs mess of a website and all the hoops to jump through in order to get the license was considered to be "the test" for GMRS.

Or "Handie Talkie".  A portable handheld radio; what many call a "walkie talkie".

For a one shot arbitrary pulse shape you can use the Fourier Transform to calculate the spectra. In a prior post I had a link for a paper that had the mathematical model for a nuke EMP for reference and testing purposes. The transform  can be used to calculate the spectra. From that the parameters for shielding can be formulated.
https://en.wikipedia.org/wiki/Fourier_transform

All of that is only good for a damped sinewave pulse.... maybe. If you know a head of time, every wavelength that will occur. Likelihood of that is zero.
 
Truth is, every frequency from DC to daylight comes from an EMP. It will be in the form of electrical, magnetic, electromagnetic, radiation, and photon energy. Even the smallest of pinholes leaves you are risk.

One of the things here that needs to be addressed is gaps and holes.
Remember folks that you are trying to keep out RF and not water.  If it happens to be water tight, so be it, but it's NOT needed.
As mentioned before, hole size in the mesh is directly related to the frequency that can pass.  For those of you that are familiar with the DUGA over the horizon radar system that is in the former USSR.  That antenna design had a reflector behind the active elements of the antenna.  If you go look at some pictures of the site you will notice behind the horizontal cage elements there are vertical wires that are running top to bottom of the structure.  Those are the reflector for the 13Mhz signal that was used for the system.  Being that it's 13Mhz the wire spacing needed to be less than 1/4 wavelength apart from each other to be effective.  But those wires in their spacing were completely effective for that design frequency. 
On the other end of the spectrum look at the large home satellite dishes that were a mesh.  Those operated at 4 to 8 Ghz and KU band was 12 to 18Ghz.  Now those mesh dishes were an effective reflector for both C and Ku bands and if the dish was physically large enough it would have worked at any frequency below the max useable frequency of 20Ghz typically.  This again had to do with the hole size in the mesh.  So small holes or perforations in the container (Faraday Cage) isn't going to have a drastic effect on the attenuation performance of the cage. 
Getting all crazy and trying to seal up the smallest pin holes with aluminum tape is pointless.  Yes, all the sides need to be electrically connected but small holes are NOT going to destroy the ability of the cage to attenuate an EMP or other rouge signal source. 
 
Something else to consider is rise and decay time of a pulse. Although the pulse is only going to have one polarity, it can still be treated as an AC source.  This is the reason that the inner and outer shields are required for a proper Faraday Cage and the EXTERIOR is the only part that gets grounded.  This creates a capacitor of sorts that is single ended with one end floating (the inner shield) and the other grounded. 
 

@marcspaz
Assuming the repeater had been established for some time, folks using a channel that’s known to be in use by a repeater is a bit like fly fishing directly beneath a dam.  Sooner or later the dam will spill. 

 

I can confirm that they are hard coded into my MP31s but I had to add them in my UV-5R GMRS.

If you choose Tone, only the transmit tone is important. Your radio will let all transmissions it receives through, regardless of the tone or lack of tone. 
If you change it to Tone Squelch, then your radio will only reproduce the audio from radios that exactly match the tone. 
I recommend not using Tone Squelch until you have a better understanding of how it works. 
Your transmissions still must match the input tone required by the repeater. 

Congratulations on making a great first impression!

Given that a significant amount of people on GMRS and in the form are also amateur radio operators and there is an amateur radio section of the form, I would say it's quite relevant. Steve's signature definitely brings more value than a single post you have made so far.
 
How about bringing some value to the conversation, instead of insults.

Hey! Don't be insulting.  We're a lot more than just comical or naive.  Some of us are *both*!

If you use an APRS cable ( Btech or other) you get much better signal transfer. Brief text and location data transfer are allowed on simplex.
Check out andFLmsg works well too, more modes, forms etc. Works better too.

Yes..
Select Radioddity UV-5R (or whatever its showing) from the list and carry on.

Why? Because features that are not supposed to be there are sometimes not there? 😄

What radio do you have?
Most importantly, channel 20 is not a repeater channel.  It doesn’t transmit on 467.675, which must be done to hit the repeater.  That’s usually shown as 20RP or something like that which transmits on 467.675 and receives on 462.675.
Are you certain that CTCSS number 22 on your radio is tone 141.3?  Not all manufacturers assign the same numbers to the same tones.  
I recommend leaving the receive (down) tone empty while getting the transmitter tone right.  That way you’ll hear everything on that frequency. 

Without knowing more about it I can only speculate, but the distance alone wouldn’t prevent it. 
So you are transmitting on 467.675 MHz with a tone of 141.3 Hz?
The reason I usually suggest that people listen without a tone is because then you hear everything on 462.675 MHz. First, make sure you can hear the repeater. If you can’t, it doesn’t matter if the repeater hears you. 
Once you know you can hear the repeater then try transmitting. Feel free to ask if anyone hears you. Most people are friendly. 😁

As far as I know there were no GMRS UV-5Rs on the market when I got my UV-5Gs, which were sold in pairs.  Anybody know what the differences are between those types?

I can see a lot of usefulness for it, since it gives you a "written record", so to speak, of information instead of relying on voice. I've done work tracking runners in 50k trail runs with no cell service, and it would be very useful to "text" runner numbers back to race control rather than dictate them over the air and have someone try to hear and write them. 

All true... I was addressing the unit's capabilities which are completely inconsistent from unit to unit
1 - There are GMRS UV-5R versions out there that ARE capable of transmitting on non GMRS frequencies with NO modification... as evidenced by the operator who entered an "emergency" TX frequency by simply programming with CHIRP. Even Randy at notarubicon addresses  that in his video review of the GMRS flavored UV-5R unit that he purchased
2 - And there are GMRS UV-5R versions out there that can TX on non-GMRS with software modification by editing the TX frequency on a memory channel in the XML file and then uploading that file to the radio. 
3 - And there are GMRS UV-5R versions out there that are locked down at the hardware level and can't even be programmed to TX on legitimate GMRS frequencies in memory channels 31 through 128.  Those channels can only be programmed to RX. I actually had 4 of those units and promptly sent them back to Amazon... what good were they if I could not even program legitimate GMRS repeater channels into the empty memory bank channels. Nothing illegal about that.
My point is that nobody knows what they are getting when they buy one... its like the scene in the Forrest Gump movie where he describes a box of chocolates as never knowing what's inside.  
 

But the good news is it might only have eight repeater channels to memorize. 😉

I don’t think it does that.

@WRYC330 The "GMRS" UV-5R is, as the name suggests, an FCC type certified GMRS radio which means it cannot transmit on any frequency outside of GMRS frequencies. The original UV-5R is not type certified for GMRS. There are lots of radios out there that will physically allow you to transmit on GMRS frequencies but it is against FCC regulations to do so.

OK, now I have to go dig mine out. 👍

This has been discussed multiple times in the past.  The rules don't really say that and quoting someone from a blog don't make it so.