quote:

Originally posted by nhracecraft:
You can string a fairly serious straightwire (or not so 'straightwire') antenna in an attic if you've got usable space. The main part of my home is 28' x 38' and I've got an 8-pitch roof! Locating an Antenna in the attic also means you don't need to worry about lightning either. The key is a usable attic...Truss construction is not ideal, and a shallow pitch roof means tight quarters if usable at all. We here in the north generally have steeper pitched roofs in order to better deal with snow loads, so in my case I've got a HUGE attic! YMMV

There was a time when a "Slinky" you made a handy antenna.

Thanks FiveFiveSixFan! I will give them a shot.

quote:

Originally posted by rduckwor:

quote:

Perhaps one of the ham radios intended for mobile installation, running off an inverter, as a member displayed earlier in this thread. In this way, a unit might be kept at home but also put into a vehicle for mobile use, unmounted.

Precisely what I have. A Kenwood mobile 2 Meter rig, a power supply and one of the mag mount mobile antennas sitting on on top of a large cookie sheet as a ground plane. Antenna sits on top of a floor lamp in my office.

Three questions:

What's the output of that unit?

How much range are you getting with it on average?

You got a cookie sheet sitting on top of a floor lamp?

When I got my ham ticket in the early 90s I remember talking to a couple regulars who had a mobile mag mount 144/440 antennas on their refrigerator and another on top of his windows air conditioner via repeaters and sometimes simplex using either 50 watt mobile rig or 5 watt HT.

Though I have not been very active in a while I always had a fondness for 40 meter SSB because it is such a great state side/Canada band and also has a good range on ground wave for local communications allowing me to talk to a lot of hams in suburban Chicago area. A full length dipole is 66 feet but my Alpha Delta DX-EE parallel diploe is 42 feet long and works very well on 40 even in my attic about 25 feet above the ground. I also had a 20 meter diploe above the roof for a while fed with twin lead ladder line and used that to work bands from 20 meters to 6 meters using my external antenna tuner. Efficiency was very good with the 450 ohm ladder line feed though the directional radiation pattern different depending on the band compared to half wave dipole radiation. Us hams work with what we have and try to make the most of it.

This message has been edited. Last edited by: grumpy1,

quote:

Originally posted by parabellum:
Three questions:

What's the output of that unit?

How much range are you getting with it on average?

You got a cookie sheet sitting on top of a floor lamp?

It's not my place to speak for someone else, but, these types of mobile units are usually limited to 50 watts and range is dependent on Frequency, power out, atmospheric conditions, obstacles and antenna height. The placement of the antenna is usually to facilitate the reception/ transmission and ground plane requirements.

This site is a really cool tool for figuring out line of sight in your area:
Line of sight tool

Move the green dot to your location, move the blue dot to the location of the antenna you're trying to communicate with. Then adjust for the height of each antenna. It will tell you if you have line of sight, and you can play with it to see what kind of antenna height you would need to hit a certain spot you would like to reach.

If you don't have line of sight, it doesn't matter what kind of antenna or how much power you have, you're not going to be able to communicate with a vhf/ uhf radio barring unusual circumstances.

Speaking of antennas, I was playing with my pair of UV-5R8W's this afternoon and experimenting with some stuff. Both are programmed exactly the same via CHIRP Next. One had the 15" Abbree 771 whip antenna on it, and the other was connected to my Nagoya UT-72G magnetic mount antenna sitting on a cookie sheet and elevated about 6 ft above the other one. I assumed the Nagoya would provide better performance, but I was wrong!

With the two radios sitting side-by-side and put into scan mode, the one with the 15" whip would lock onto incoming signals as well, and frequently even better than the Nagoya!

Maybe, just maybe, the difference is because the Nagoya is the GMRS version, but I was still surprised by the results.

Comments from the experts???

Imagine a very wide lazy V shaped pattern and compare it to a very sharp V shaped pattern. then draw a horizontal line and on one side mark it 400the other mark it 500. then place the bottom/center of the wide V at 440 and then place the bottom center of the sharp V at 465. with that illustration you can then visualize the sharp V will get the desired frequency better and stronger than the wide V, but the Wide V will have greater frequency coverage, all be it weaker, over the other parts of the spectrum. this is why better receivers are important. and this is the difference between a tuned GMRS antenna and a general purpose UHF antenna. You also have to make sure you are comparing apples to apples when testing antennas. one may do well at certain frequencies and the other may do well at other frequencies.

quote:

Originally posted by Perception:
This site is a really cool tool for figuring out line of sight in your area:
Line of sight tool

Move the green dot to your location, move the blue dot to the location of the antenna you're trying to communicate with. Then adjust for the height of each antenna. It will tell you if you have line of sight, and you can play with it to see what kind of antenna height you would need to hit a certain spot you would like to reach.

If you don't have line of sight, it doesn't matter what kind of antenna or how much power you have, you're not going to be able to communicate with a vhf/ uhf radio barring unusual circumstances.

I believe this tool will solve more problems and answer more questions than anything else.

Thank You for posting this.

quote:

the one with the 15" whip would lock onto incoming signals as well, and frequently even better than the Nagoya!

Let us know what frequencies they were locking in to.

The further from GMRS frequencies, the advantage would go the the dual-band whip.

The UT-72G is dual band and the same antenna as the UT-72, but about an inch shorter. That difference moves the center VHF from about 146MHz to 152MHz and the center UHF from about 435MHz to 465MHz. In other words, the UT-72 is dual band for 2-meter and 70cm HAM, while the UT-72G is dual band for MURS and GMRS.

I doubt there’d be much difference in reception between the two.

I suspect the difference in reception performance between your whip and UT-72G is location based, especially if you are using them within your home. Reception on my radio changes just by turning it from vertical to horizontal and also changes as I walk through my home.

Me, watching everyone graduate from ham radio school, from high up in the gym bleachers: {takes swig out of bottle of beer, flicks ash off of cigarette}

Teacher approaches: Dude, what happened??

Me: I got left back for another year.

Teacher: Why??

Me: {shrugs} Flunked Antennas.

quote:

Originally posted by parabellum:
Me, watching everyone graduate from ham radio school, from high up in the gym bleachers: {takes swig out of bottle of beer, flicks ash off of cigarette}

Teacher approaches: Dude, what happened??

Me: I got left back for another year.

Teacher: Why??

Me: {shrugs} Flunked Antennas.

if you wish to understand antennas study RF propagation.

quote:

Originally posted by trapper189:
The UT-72G is dual band and the same antenna as the UT-72, but about an inch shorter. That difference moves the center VHF from about 146MHz to 152MHz and the center UHF from about 435MHz to 465MHz. In other words, the UT-72 is dual band for 2-meter and 70cm HAM, while the UT-72G is dual band for MURS and GMRS.

I doubt there’d be much difference in reception between the two.

I suspect the difference in reception performance between your whip and UT-72G is location based, especially if you are using them within your home. Reception on my radio changes just by turning it from vertical to horizontal and also changes as I walk through my home.

Not to mention when you use an HT you end up being part of the antenna for better or worse. Inside the home becomes a more complex situation too depending on proximity to electrical conduit, metal pipes, ductwork, windows, etc.

From our friend NotARubicon.

quote:

H.A.M. radio is just a gateway to GMRS.

https://x.com/TheNotARubicon/s...363171497291965?s=20

Originally posted by parabellum:

Three questions:

What's the output of that unit?

50 watts max

How much range are you getting with it on average?

Really haven't pushed it. I can hit our main repeater about 12 miles away with ease. I am on the bottom of a ridge that sits between the repeater and me.

You got a cookie sheet sitting on top of a floor lamp?

Yep. Don't tell my wife. She hasn't missed it yet. Makes a decent ground plane.

My primary useage is severe weather. We have a very active SkyWarn group in the local Ham club and also a good ARES group in my home county.

RMD

---

TL Davis: “The Second Amendment is special, not because it protects guns, but because its violation signals a government with the intention to oppress its people…”
Remember: After the first one, the rest are free.

quote:

Originally posted by ltz400:

quote:

Originally posted by Perception:
This site is a really cool tool for figuring out line of sight in your area:
Line of sight tool

Move the green dot to your location, move the blue dot to the location of the antenna you're trying to communicate with. Then adjust for the height of each antenna. It will tell you if you have line of sight, and you can play with it to see what kind of antenna height you would need to hit a certain spot you would like to reach.

If you don't have line of sight, it doesn't matter what kind of antenna or how much power you have, you're not going to be able to communicate with a vhf/ uhf radio barring unusual circumstances.

I believe this tool will solve more problems and answer more questions than anything else.

Thank You for posting this.

You're welcome.

Yes Perception, thank you. That tool is awesome and based on my connections and lack there of, it is right on the money.

quote:

Originally posted by bronicabill:


Maybe, just maybe, the difference is because the Nagoya is the GMRS version, but I was still surprised by the results.

Comments from the experts???

If your radios are the Ham version (And I haven't kept up with the various models over the years - so I don't really know what freqs your are designed for), no surprise. The Nagoya is specifically tuned for the GMRS freqs, not Ham 2 Meter freqs.

One thing I can tell you is that if you buy one of the mag mount antennas from whereever, be sure you loosen the set screw and remove the whip component. Make certain to sand the paint off the end of the whip to allow for good conduction from the base to the whip. I was sorely disappointed with mine when I first tried it and then I remembered this trick from the CB days.

RMD