antenna in a metal box

[joseph2020]

I live in a mobile home, a big rectangular box, completely encased in metal. I can see there are some great indoor antennas out there for apartments and rooms in houses, but I'm guessing nothing is going to work inside a metal box.
(1) is that always true?

(2) If I set up an antenna outside and then bring the feed line (shielded coax) through the metal wall into the radio room, will that work?

(3) What if I used the concrete utility shed outside, next to the home (about 10 feet away)? This would be the roughest alternative as I would have to find a place for all the stuff in there now...only if nothing else will work. Any opinions are welcome. Thanks in advance.

 

[WA1ATA]

If I set up an antenna outside and then bring the feed line (shielded coax) through the metal wall into the radio room, will that work?

Yes, that's the best solution. In this case being the metal walls of your mobile home have no effect. The metal roof is a suitable mounting for mobile antennas that are designed for mounting on top of a car and use the metal car body as a groundplane.

You may also find that simply tacking your antenna up to a window works.

How much signal manages to sneak into your mobile home depends a lot upon the frequency. Higher frequency signals, such as 800/900MHz that have wavelengths less than the window size will generally get through with less attenuation than VHF.

What makes the most sense depends a lot on what you are trying to monitor. If you are just trying to monitor the local PD, it may turn out that their signal is so strong that a rubber ducky antenna on your scanner gets enough signal to work well.

 

[LtDoc]

Think about it. If that metal 'box' shields the antenna from receiving a signal it just isn't going to receive very many signals. So getting the antenna outside of that metal 'box' would be a very nice thing.
Or, you could turn that metal 'box' into the antenna. Not an easy thing to do normally, but possible. The first thing that comes to mind would be to lay in a good ground system under that 'box' for the antenna's 'other half'. Then the 'box' just becomes a weird shaped antenna working off of that ground system. Lot's of "if's/and's/but's" in that, buyer beware, sort of...
- 'Doc

 

[KC4RAF]

In response to using the metal siding

as an antenna; SOME local juridictions require the siding to be grounded, thus reducing the possibility of electrical shocks. This would not be good for use as an antenna.
Reference:
Grounding aluminum siding - InterNACHI Message Board
Where not grounded, then it might work to you advantage.

 

[joseph2020]

WA1ATA, LtDoc, rafdav, Thanks for your replies...sound like antenna on the roof with the feed line into the radio room through a hole in the metal siding and inner wall is the easiest and most effective answer.

 

[joseph2020]

issue resolved

I think it's safe to say my question was answered, thanks to all.