WRXB215

Here’s a guide to losses expressed in dB:
Losses:
-1.5 dB = 25% loss of power
-3 dB = 50% loss of power
-6 dB = 75% loss of power
-9 dB = 87.5% loss of power
-10 dB = 90% loss of power
-20 dB = 99% loss of power
-30 dB = 99.9% loss of power.
 

You really need to analyze everything after the radio as a “system” looking at cable losses and antenna gains. I did a simplified one for the antenna install I want to do on my Mazda. What you loose in the cable could be made up to a degree with gain in the antenna. See attached files.
 
Diamond C110 Extension Cable.pdf Diamond C101 Cable Assembly.pdf Diamond K550 Luggage Rack Mount.pdf Mazda 2023 CX-5 Antenna System Analysis Rev 5.pdf SG7500A.pdf CA-2x4MB Manual.pdf
https://forums.mygmrs.com/gallery/image/282-ca-2x4mb-scansjpg/?context=new
https://forums.mygmrs.com/gallery/image/283-sg7500a-swr-scans-2jpg/?context=new
 

Little bit of expansion on the discussion of DIY cages.
I have worked with commercial Faraday cages in the past doing RF work.  Reasoning was you can't truly evaluate the performance of a radio receiver when it has multiple RF signals near it. 
The commercially sold cages we used were a sheet metal room (technically sheet aluminum and not metal) with an aluminum frame that the outer shield was screwed to. It was also glued with a conductive construction adhesive.  The door on the unit was staggered and 6 inches thick with the inner face reaching into connect to the inner shield and had finger stock that surrounded the inner part and a separate ring of finger stock on the outer ring.  There was enough room in the cage for a workbench and the required test equipment, a chair for the desk and a bit of space to move around.  It was probably 6 by 6 or 8 by 8, but no bigger.  Special electrical filters were connected to the power feed for the interior and while there was a 'window' it was inset into the door and has copper screening on the interior and the exterior hole was also screened.  So it's technically possible to have a window, it still needs to maintain the 100% shielding inside and out.  Air ducts were connected to the HVAC but there were special screens that needed weekly attention to keep them clean as the screen material was a very fine mesh and collected a TON of dust and crap.
 
Again, there is no really secret sauce for building a cage.  The info is on the web. 
 
 

So far there are only two radios I’m aware of that can operate digital voice on the Ham 1.25m band, the Kenwood TH-D74 currently and the Anytone D578 mobile. 
 
The TH-D74A only does D-Star while the D578 does DMR. I wished Kenwood would have given the option to do DMR with the TH-75A. They likely couldn’t keep them in stock even at a $700 more or less price point. I get the feeling that DMR is slowing replacing D-Star.
I talked to the Kenwood rep at the Hamvention last May asking why no DMR. He told me the offices here have been telling Kenwood Japan the same thing for a while, but nobody wanted to hear it in Japan. People that want DMR in a Kenwood radio have been buying their commercial radios. That’s why I own several. I’m surprised they haven’t figured this out yet.
 
Wait and see Icom do it, maybe even offer both, then see how the sales do on the TH-D75. Kenwood isn’t stupid. They know how to do multi protocol radios. They do it now in their commercial lines.

I agree with Steve.  Truth is, you need to measure to see if its worthwhile.

It could go either way.  If it’s much too long I would cut it off.  If it’s just a few feet I would live with it, which is what I do with the few extra feet of cable on the floor behind the passenger seat now. 😀

What you are experiencing is tropospheric ducting. It’s a wonderful thing, made a 92 mile confirmed DX with it earlier this year on simplex.
Here’s a forecast map:
https://www.dxinfocentre.com/tropo.html
And explanation
https://www.dxinfocentre.com/propagation/hti.htm
https://www.dxinfocentre.com/propagation/tr-modes.htm

As mentioned by @Borage257, especially due to the time of day and the time of year and what the forecast has been, you are near certainly experiencing tropo ducting.
 
That said, you touch on something that many people grossly overlook, including radio pros.  Although we discuss VHF and UHF radio being a "line of sight service"... that doesn't mean that atmospheric conditions impacted by solar cycle don't impact VHF and UHF... particularly in the case of GMRS.  In fact, during the day, they can have a profound affect in either increasing range or swinging the other way, causing radio blackouts.
 
UHF signals actually travel comfortably beyond the visual line of sight, by about 15%.  This is due to refraction and scatter affects in the atmosphere.  The more loose, electrically charged ion particles are in the air, the more scatter and refraction you get.  This translates to better signal quality at distance and often, a small bump in range.  The ionization in the F region increases roughly 2 × 106 e/cm3 during maximum sunspot activity.  The F1 layer is the principle reflecting layer during the day in the summer.  This is why some bands perform much better during the day.
 
While these principles have more and more of an impact as you go lower in frequency, the lower the takeoff angle and the more the solar weather is spicing things up, the more likely you are to have a significant amount of your UHF signal refracted and/or scattered back to the earth beyond the horizon.
 
As an example, during a contest back in 2009, I was able to use a stacked beam array and 1,500w to make a contact on 146.52 MHz from a mountain top in Virginia to central Texas.  On that same day, I was also able to make a contact on 446 MHz to Tennessee, near the Arkansas state line, using the same kind of setup as the VHF contact.

Hey! I resemble that remark!

Those are pretty neat!  I think if you're going to be traveling a lot, that can be something to help keep you company while driving.
 
I was supposed to be going to Moab, but I get very sick twice this year.  We rescheduled for August of 2024.  We're going to do some desert runs in SoCal, the Rubicon, Black Bear Pass, then head to Utah.  Planning 3 weeks in total.

Well, if we are gonna get into 'real' Faraday Cages, then lets actually talk about their construction.
First off, they are layered.  There is an outer and inner layer and they are NOT connected together. 
Hole size in the shielding material is what sets the minimum / maximum frequency that is blocked.  In other words.  A fine mesh will block a higher frequency than chicken wire will with 1 inch holes in it.  Consider the holes with regard to frequency wavelength.  If the hole is larger than the wavelength of the frequency in question, it will pass right through like it wasn't even there.
A strong understanding of the signal level and the attenuation level of the Faraday Cage needs to be taken into account.  A cage is not a perfect attenuator.  It has very high attenuation levels, but a signal that is strong enough will get through at a much reduced level. 
 
Proper construction.
A 2X4 or 2X6 frame is sufficient spacing to get a very high attenuation level with modest materials.  Those being standard wood framing and aluminum screen. For an added sense of security, thin sheet metal can be used in place of the screen.  You have an inner layer and an outer layer.  of the conductive screen material.  And remember they can't in any way be connected or you will loose attenuation properties.  The other thing you need is a GOOD earth ground.  This is not the 1 or 2 ground rods that are grounding your electrical service entrance, you will need to do better and it's advisable that the grounds be kept short as possible.  So if you are planning on building a cage, do it on the first floor or in the basement near an outside wall so you can get the ground wires out the wall and to the ground field withthe shortest wire possible.   Longer wires equal bigger antenna's and you don't want that. 
To put a door on the cage, you will need to ensure that the entire perimeter of the door be connected to the screens, both inside and outside.  Couple ways of dealing with this is either finger stock, copper or other metallic door trim / weather stripping, or construction methods that taper the inner and outer screens in a way that when the door / cover is in place that a 100% seal exists in all locations around the door inside and out.  
Again, can't say this enough, the INNER shielding material is NOT connected to ANYTHING including the outer shielding material.
 
For those that are looking to play around and build something similar to the professional level cages, this should be a good starting point.  Sure you can locate copper screen and use that.  It will work the best but it's also very expensive.  Not worth the money to protect your Baofeng radios. 
 
If you are REALLY wanting to go for broke and build a large cage, and be able to occupy the space, there are methods of bringing power and RF into the cage, but special filters and methods are required and are put in place outside the cage and are bonded to the same ground as the outer layer of the cage.  Remember that you need both layers of screening on all sides, including the roof and floor.  There is no reason that you can't set the floor screen and then sheet over it with layers of plywood or other subflooring material as long as the screening isn't molested (floating floor material.And of course you can also drywall the walls and ceiling but it's advisable to use construction cement and not screws to fasten the drywall to the framing.  Screws can be used sparingly to assist in placing the drywall until the adhesive is dry but will need to be removed after that happens to ensure the best isolation.  If you bring electricity into the cage, do NOT bring a ground with it and you HAVE to use an isolation transformer with proper filtering right at the entry point on the OUTSIDE of the cage,  DO NOT use conductive conduit to route wiring through within the inner shield. 
Detailed construction instructions are available on the web for building a Faraday Cage.  Study those plans carefully and scale your project to your needs.
 
 

I’m much more concerned with non-emp power outages. Our local region has enjoyed record highs and several storm related power outages this year. Having robust power backups on individual radios (ht/mobile/base) as well as local repeaters is paramount.
IMHO grid down scenarios are more likely to happen from neglect, accidents, and non-emp terroristic acts than nation state or wide area emp strikes. I hope I’m right.
“Grid down, power up” is an interesting and somewhat sobering discussion on the state of the grid

Apparently emi gasket works. You’d have to take a wire wheel to the lip and inside of the seal are then apply the emi gasket.

As Steve said, no but, it is always good to check the VSWRs on a new setup just to make sure you're not reflecting a lot of power back into the radio by having a bad connector of a defective coax cable. It does happen and a lot of reflected power will affect the power output and you will have a poor performing antenna system regardless if the antenna is properly tuned.

I tested an ammo box using radios (2m HT with rubber duck antenna) and it still RXed.  I figured it was because of the rubber gasket.  Old gutted microwave worked though.

It wasn't high enough, not even close, to cover a large area.  And yes I saw it, and 2 fighter jets that approached it.

I have a few thoughts on that. While a lot of criticism was leveled at the government for waiting to shoot it down over the ocean there might have been a legitimate security reason for it. Getting photos is one thing, but I think the main purpose was to monitor our military communications systems and gage our response procedures and times to an unknown threat. If China invades Tiawan that would be very valuable Intel. Waiting until it was over the ocean to respond sort of wasted their efforts in that area.

I don’t know for sure, but I would be optimistic. But for God’s sake don’t pay $100 for one just because a preppier supply company sells it.  Find a local surplus store.  I think I paid $10 for a 30 mm ammo can a few years back.  If you absolutely cannot find something locally at least shop around:
https://www.cleanammocans.com/50-cal-ammo-cans.html

That would surprise me, but I have no actual knowledge.  My gut tells me it was more likely just for electronic surveillance, slowly passing over the US collecting signals while passing intelligence to Chinese satellites to be relayed back to China.  

I spent the last 13 years of my career in the control center for an electric transmission system. I supervised the team that maintained the Energy Management System (SCADA) software and hardware that controlled the electric transmission system.  We spent nearly all our time making sure the Energy Management System worked well with hot swap redundancy at every level in the control center.  Every electric transmission system has such a control system which controls energy transmission substations across huge sections of our three national grids.  Loss of a single control center or our largest substations has significant effects on the grid. Fortunately, such losses happen very infrequently and our systems are built to be restored quickly.
But, those EMP weapons, tiny as you say, would be sufficient to completely destroy the controls for our largest electric substations and control centers. Or any other cyber or communications infrastructure.
I think an atmospheric nuke, causing an EMP as a side effect, is a highly unlikely occurrence.  There are only a few countries which have the capability and for the most part there are checks and balances.  
But, it’s just a matter of time before a suitcase sized EMP only device is deployed by some small political or religious extremist group.  It’s the ideal weapon for group that might wish to “bring our evil society to its knees” but that might also have a fundamental aversion to taking lives.

It has been advised to me from an Anytone technician that there are many Anytone versions of the AT-779UV. Use CPS version 2.01 and change the radio service in the CPS and then save first file. Then restart radio and read from the radio into CPS. It should give you all common GMRS channels. My Version of radio from Let's Get Ready did not have GMRS option in start-up. I had to change it in CPS 2.01.  Remember every time the format is changed in radio all memory will be erased. So Using as a ham or part 90 commercial radio or GMRS Part95e, make sure to read from radio and save file i.e. "Ham radio 9/6/23" or GMRS radio 9/6/23" Alwayts date and save you last updated files in a folder so you can go back to older files if necessary. 
RJ
 
 
 

Not only is this statement factually true... but in my opinion, the decade of the absent enforcement has led to the ridiculous behavior of jammers.

@Blaise I assume they are just giving the accused a chance to have their say before anything else happens.

@Blaise I assume they are just giving the accused a chance to have their say before anything else happens.

That’s how all of the letters from the FCC seem to work. FCC sends a letter, a notice of wrongdoing, asking the accused to explain why they’re innocent or how they’re going to avoid future transgressions. If they give a satisfactory answer that’s often the end of the matter. It’s as if the assumption is that most people don’t intentionally violate the regulations and with some remedial measures they will do better. 
Personally, I like that. Based strictly on observation I would agree that most people don’t understand the regulations.  Why not give folks a chance to do better instead of crushing them after one mistake.