A while back I bought an old Kenwood HF station and Hustler vertical multiband (I think 5BTV with 80m add on).

I've been hesitant to set it up for 4 reasons:

Concern for RF exposure:
   -I'm on a small lot and am not sure how to setup the antenna to minimize RF exposure to family. Maybe put it by garden, but how far away does everyone need to be when transmitting? What's the best way to measure RF exposure and what's safe? Some people say no concern at all, others say big long term health concern.

Concern for grounding:
   -I think if I save up for the mounting plate from DXCOMMANDER and get a flush mount box with grounding bar for house I can be safe from lightning. I've been tempted to follow the advice for others here and run through window to hook up when using then disconnect when not. The radio has a ground screw on the back and old school two prong power. Not sure best way to power it up without some kind of grounding bar, and no idea how to setup grounding bar to outside (without the outside terminal box).

Concern for radials:
   -I don't have space for a ton of radials. I've seen some videos that say one radial for each band run along baseboard in bundle will work, others say at least 2 radials per band 180 degrees apart and separated.

Concern for SWR:
   -I'm currently borrowing an old meter that can measure SWR on VHF/UHF for sure, but not sure how I would use it to setup each band on the vertical. I'm looking at the NanoVNA, but confused on which one to get.

I see models by Aursinc and Seesii.
2.8" NANOVNA-H 10kHz-1.5GHz
4" NANOVNA-H4 10kHz-1.5GHz
4" NANOVNA-SAA-2N 50kHz-3GHz
4.3" NANOVNA-F 50kHz-3GHz

4" TINYSA ULTRA 100kHz-5.3GHz
4" NANOVNA 50kHz-6.3GHz

Anyone have thoughts or helpful advice on any of this?

I think you are more concerned about RF exposure than you need to be. I'm sure someone here can quantify what risk there is for the wattage you'll be putting out (100w? I didn't notice a figure), but you're not exactly going to be running a 50kw commercial AM station where there is serious concern. Don't grab the end of the antenna while transmitting.

As for the NanoVNA, I can offer some info. They are an open source product, meaning the circuits and parts list are known, so every 2-bit Asian sweatshop can make and sell them, with predictably variable quality.  When I wanted one so that I could see what my antenna was doing, I decided to buy one from a ham radio oriented business, because I have more faith in them offering something decent than I do Amazon or some random seller somewhere. R & L Electronics is who I bought mine from.

https://www2.randl.com/index.php?main_page=product_info&cPath=15_8620&products_id=75242

Nice heavy duty metal case.


In my opinion, the best way to run a NanoVNA is from a PC. This is the free software I use to run my NanoVNA: https://github.com/NanoVNA-Saver/nanovna-saver Scroll down to where it says installation.  I use a USB cable to connect the NanoVNA to a PC and run it from the PC. The touch screens on these things are not great, so running it from a PC is the way to go. Plus, your results are displayed on your big monitor and the software provides easy calibration and settings adjustment.

That SAA is one I had looked at. Did you need to buy specific adapters for N-type to SO239/PL259, or BNC, or SMA?

Is there an advantage of this one over the H4 or F models?

Here is an ARRL RF exposure calculator, it includes the max recommended.

But basically at 100 watts, as long as people are outside of 3 feet from the antenna, you are fine based on recommended exposure levels.

My 2cents.

Rf "Exposure " will be the least of your concerns.

You are about to embark on a journey of Radio frequency interference.

A vertical next to a house is just about the worst possible place.

Especially if you do not have room for radials.

Putting any part, of any antenna "next to the baseboard" is just wrong. :)

And your rig has a VSWR meter. If you need to ask which nano to get, you should hold off on it for a while. With the antenna next to the house, with one radial, attached to the house...you will NOT be able to adjust the antenna for a satisfactory VSWR regardless of how much you $pend on the meter.

And yes, you need to read up about "grounding". Real short, you need a "ground rod" at the antenna,  and a wire connecting that rod to you existing house safety ground.

.....

Now that same antenna, on the roof, with 2 radials for each band and you will have a respectable signal.

Or if that's not possible, a simple center fed halfwave dipole up in the trees.

Anything, anywhere but next to your (and your neighbors) house.

Rege

I didn't have to buy anything else to be able to use it. It came in a nice zipper case and included all the adapters for the regular coax connectors (239/259).

If you scroll down on the R&L page you'll see images like this one. The adapter is the part just below the couled USB cable.



As to advantages over H4 or F models, I have no idea. Maybe someone here has studied them enough to know. I just kind of threw up my hands and bought the one I linked.

All I really do with mine is calibrate it then run a separate analysis for each of the bands I use. I calibrate it each time for each band rather than using a stored calibration value because I know that it is good. I then use a screen capture tool, to grab the results and throw that into a doc that I make into a PDF so I have a record of my results.

It also gives me Smith Charts, but I don't save those. Example:

With no Amp and the gear you describe, I feel like RF exposure is not even a thing.

Now the grounding is where I'm stuck at on my shack 2m, 6m and HF antenna setups.
I can ground it (3+ 8' ground rods) fairly easy, but with the way my house, basement, main panel, various concrete and other obstacles are laid out, bonding it in any meaningful way, is a HUGE thing...

Depending on work/weather and Honey Dos projects, I'm hoping to get a enclosure mounted to my small tower next to my house this week, so that I can put 3 or so Polyphasers (for my antennas) in there to try and keep spike and unwanted "voltage" out of the shack...

At 100 watts on HF, you're practically going to have to be doing chin-ups on the antenna to exceed exposure limits.

As  for SWR, no need to get anal about it. If your radio's internal tuner can match it, you're going to work stations. Hell, on 10 Meters where HF feed line losses are highest, I've worked DX running 50 watts into an antenna with SWR so high the return power meter was pegged out. On 15 and 20 meters, my trap/fan dipole has an SWR of about 3:1 and DX is an everyday occurrence. When propagation is favorable, 5 Watts will easily "jump the pond". Get it down as low as you can and have fun.

As for measuring the SWR, just get the reflected power as low as you can. I use a 30 year-old version of one of these:


As for grounding, I share Smullen's problems, so I just disconnect and roll back the coax so it's away from the house.

If that antenna is overwhelming, just buy a g5rv and be done with it for now. I operate 5w normally with my IC705 and a g5rv at home. I mainly do digital modes with some CW, not really into SSB. I've made ft8 contacts to Japan, 5000 miles with 1w 3 or 4 times this month, if the bands are in my favor. My furthest contact 10,600 miles with 10w to Antarctica, 9600 miles to Angola. Indonesia with 5w just the other day. Sometimes you just need to simplify things to get started.

@ajroyer
One concern is touching the ground mounted antenna when it's hot. Get some plastic fence and some uprights for the electric fence that push into the ground. Build a square or circle where the fence is at least 4 feet from the antenna. Have enough of the supports to be able to open it up and weed whack. Use lawn staples to hold down radials. You will want to bury the coax if it's all ground mounted. It's better if up in the air 10 feet or so and exposure to RF and high voltage are not a problem. hth
73,
Rob
ETA: For 10M, a cheap CB antenna up on a pole will do the trick. It may need tuning, but that shouldn't be a problem. I'd rather see a multi band antenna as an incentive to upgrade.

Yea RF exposure is a non issue at HF frequencies. When you get into microwave and other high frequencies it does become an issue and RF exposure study should be done. But we are talking very high power and highly directional antennas are required to reach exposure limits.

Attached File


Wife bought me this when she seen I put it in the cart. RF exposure is frequency dependent. Like other have said you will have more issues with noise on a vertical antenna. I would make a dipole for whatever band you plan to run and just put it up and get some time on the bands. There are mobile stations running legal limit screwdriver antennas.

VHF is where things get spicy.  That's where the human body ("HBM", "Human Body Model") absorbs RF energy the most.  
FM Broadcast array, 10 element rototiller with about 10kW being fed into it.  3-1/8" hardline.  I'm about 15ft below the bottom element, and at full 10kW (50kW ERP) my alarm was screaming.  Backed it down to about 2kW at the transmitter while I was working up there.  Most of the energy is radiating outwards, not downwards, but i'm still damn close to a lot of energy.


Microwave is dangerous due to forward gain and localized heating effects.  Don't stand in front of dishes.
Worst dish placement ever.  ~2 watts, 11GHz iirc.  Might be 6GHz.


Use the ARRL's calculator, it's good enough for amateur use.  Professional work has better modeling software tools that take specific antenna design/models into account.  
I'm around a lot of antennas and in fields of transmitters I don't control, so I have a personal RF monitor when i'm climbing or working around broadcast sites.  They're expensive.


Bottom line, you need a lot of power into a lot of antenna before exposure becomes a real concern.  
Got my nardalert on the charger right now, i'll be hanging two dishes with new ether runs and peaking one short-haul dish on a tower on one of the hottest transmit sites in the state on friday.

You can take this information to the bank as he is a professional that has OSHA and FCC guidelines that need to be followed. Leakage from your microwave oven probably has more exposure than HF rig with 100w ever would. Would be a cool test to see what has more exposure using the Nardalert and see. Looks like there is some of those on Ebay for a good price.

the hustler trap vertical needs a bunch of ground radials. i buried mine a few inches under the grass

it needs carefully tuned, starting at 10m, and working your way up the antenna

it’s tedious work, lifting it up, testing SWR,..dropping it to adjust…over n over

…but if you do it right, it’s a great antenna

half-ass it,…and you have a dummy load

DX ENGINEERING has the best install PDF

I run a 200watt HF mobile and dont worry about RF exposure

OP, how about a sketch of your property with trees, buildings, and approximate dimensions? If favorable, perhaps it would be better suited for a wire antenna. They are inexpensive, easy to make and would probably use less wire than radials for the vertical.

For tuning multi-band trap antennas, start with the highest frequency band (10 Meters) and work your way down. For wire antennas, start with the lowest frequency band and work up.

How To Tune A Dipole Antenna

You almost certainly dont have less room for antennas than my current house……. And I have a 6BTV about 4’ off the side of my garage and a 71’ random wire in a crazy sloping horizontal L thing about 20’ up going to a “tree” i made from a 16’ 4x4 and a 10’ pipe clamped to it. (My only tree came down in a storm and smashed my house, lol)

Radials? Well, i ran a bunch where I could. I am up against the garage in one direction and my property line is close the other direction……… so they mainly just run east and west…… not north and south.

I have worked over 100 countries on ssb and about 130 total with those antennas and 100W. I am able to check into rhe tuesday arfcom net just as often as others depending on conditions. 100W exposure is not something I am worried about for me personally. But I have been described as reckless in more than a few contexts…. So……. I dunno.

NanoVNA….. works great for me. I just bought one from a vendor on amazon with a crap ton of good feedback.

Do you know if there there any inexpensive RF monitors available that would function similar to your Nardalert?   Looked at several on Amazon and don't trust any of the reviews.

@SnowMule I am curious about this too. Any recommendations?

I tried to hook up a 220 vertical, just to see if I could receive anything.

I can't.

Got motivated to get the 5BTV up. It's a disastrous hodge podge of wire and adapters right now.

I got some 14ga THHN stranded wire on clearance and cut radials. The instructions say 8'4", 11'4", 16'4", and 32'4".  Ordered some SO239, PL259, and a couple odd adapters to try to get a better feed line.

What should I try to tune up to see if it's working?  Any solid CW or SSB on specific band? I need to see if I can get my little NOOELEC SDR dongle reading waterfalls to try to locate signals.

Fieldsense units are about the cheapest ones out there.  Still gonna be $500+.  

11 TV transmits, 19 FM transmits.  Plus a pile of two-way, public safety, ham, microwave, scada/telemetry, cellular, satellite uplinks/downlinks...
Around that much power, guy wires will illuminate and re-radiate from the high power stuff.  My nardalert bleeped and booped and vibed pretty often through the day.


It's one of the spiciest sites in the state, but the site owner does a really good job surveying, monitoring, and communicating the exposure hazards.
Inside this handbook is a bunch of references to the hazards of RF exposure, difference between controlled and uncontrolled environments, placarding around the site, test methodologies, calibration certificates for the equipment used to do the surveys, map of the site with locations/power outputs/antenna gains of the transmits and the points where data was taken, along with a summary of and test data from the surveys.
ARRL (amateurs in general) got lumped into the same regulations as the broadcast engineers did when it comes to doing the exposure calculations.  It wasn't designed to burden amateurs, it was designed to standardize the RF licensing process across services.  

I have the big DX Commander, it's sitting 20 feet from me.. now it isn't setup because I'm lazy. I've done all the cutting and prep work, but I don't have the coax to get it where I want it, and I'm lazy.

This is Arfcom. Go for the Nardalert. What's $3700 worth of unnecessary (in this case) gadgetry.

Real RF exposure is no joke. Your 100W ham antenna is nothing to be concerned about unless you're licking it while keying up.

I know that's what the instructions probably say. Those are free-space 1/4 wavelengths for 10/15/20/40.

I would say the instructions are wrong.

N6LF did a bunch of testing, and I repeated a little bit of it, enough to convince myself that his info is right. This is for ground-mounted antennas with radials on the ground, not elevated radials.

If you have a lot of radials, like 64~128 like the AM broadcast folks use, then a full 1/4 wavelength works great. If you have an installation that allows for elevated radials, then full 1/4 works great. If you have a small number of radials on the ground as is more typical for amateurs, dielectric effect of the soil below means the radials should be significantly shorter than a full 1/4 wavelength. Common soil conductivity, 20 to 21 feet works well for 40m with 4-8 radials. Scale other bands down by the same kind of percentage (60 to 65 percent of free space 1/4 wavelength).

N6LF's findings were pretty dramatic. Take a not-uncommon case of 4 radials. The signal difference between the 20 foot length and a free-space 32.5 foot length was like 5.5dB (!). Almost a full S unit, just from the radial length.

The shorter length also means you can put more radials out per amount of wire that you have which improves things even more.

For a multiband antenna, putting out say 4 each per band seems to work well. I had an antenna up for a while with 8 each for 40 and 20 and 4 each for 30 and 17 and it worked very well. If I could get my FT8 comparison software concept working I'd test it.

Something else I found on radials. In my rural location, insulated ground radials get gnawed on by rodents and damaged. Bare wire doesn't. I usually use aluminum electric fence wire which is inexpensive.

OP

you’re already bombarded by RF exposure right now

Shortwave broadcast

AM broadcast

FM stations

TV

public service

cellular

….stop worrying about it, or find another hobby

at HF freqs, it’s a non issue

.

well, yes, but at significantly lower power densities than you'd get right next to a transmitting antenna.  
Inverse square law n' all that sciencey stuff.

If you havent invested in 5g blocking underwear by, its too late anyways.

exactly

Some magic waves I can't see ain't starting me wearing underpants.

Whatever you do, put up a big, scary sign next to your antenna saying it is an RF hazard and will melt your brain yada yada yada.

It'll generally keep the kids away and with any luck you can get the Karens all worked up!

Danger! Touching antenna causes instant DEATH!

I appreciate the thoughts and suggestions. My terminals came in and I acquired some TWS400, which appears to be a brand of LMR400 style coax.

I have my antenna end prepped. Now I just need to decide on it's home.

"Feel the burn!"


the broadcast tower is pretty hot, and getting up here there's a spot where you're right in the beam of a microwave dish.

Is that a KTM?

1190 Adv R.