Field Strength Meter

[jdchet]

I feel the need to buy a Field Strength meter. I'm going to try something a little different, than in the past, with the new truck antenna install. Do those cheap Astatic SWR/Field Strength meters work okay or do we need to spend some serious coin on a meter. This would just be for my own personal use.
Planning on mounting a 5' Skip Shooter on the back of the sleeper.
New Truck with the typical trailer we pull



JD

 

[Smokinone]

I've used the cheapy's up to an MFJ analyzer, and they are are pretty close in what they read as far as SWR. Just make sure you get one that is rated for the power and frequency you might put through it.
Of course the more you spend the better meter you get, more features, selections, accuracy etc.
Just my opinion, and I've used a lot of different Radio Shack meters with good luck.

Nice looking truck by the way.

 

[jdchet]

Not concerned with SWR. Have a RigExpert and MFJ meter for that. Field strength is what I want to measure.

JD

 

[Smokinone]

Sorry, I misunderstood.

 

[jdchet]

Sorry, I misunderstood.

All good!

JD

 

[sp5it]

So easy to DIY. It's like 1 hour, 10$ project.

 

[jkp1]

So easy to DIY. It's like 1 hour, 10$ project.

Tell me more

 

[sp5it]

Field Strength Meter (FSM) using OA91 Diode

In this tutorial, we are going to demonstrate a project Field Strength Meter in detail. In general, The field strength meter is a signal

www.circuits-diy.com

I would use analogue multimeter for readings.

Stand-alone device: https://4x5mg.net/2018/07/10/passive-field-strength-meter/

 

[unit_399]

You don't need an expensive meter to make a field strength measurement. I use a cheapo Radio Shack meter and it does a good job. The secret is to use a much larger FS antenna than the one that comes with the meter. I use a 3' whip out of an old K40. Increases the meter sensitivity by a bunch.
To make the measurements, park your rig in an open field or parking lot. Keyup and walk around it in a 20' circle or so. Draw a circle on a piece of paper and write down the readings every few degrees. If the meter pegs out in a lot of places, just reduce the sensitivity by turning down the SWR CAL control and measure again.
Not rocket science, but it will give you a very good idea as to what your pattern looks like.

- 399

 

[Captain Kilowatt]

There are basically two types of field strength meters. One reads true field strength and displays the resulting power density in volts/meter or usually millivolts or even microvolts per meter, and basic meters that simply show a relative reading which means nothing except as a reference. Broadcast stations use calibrated meters to indicate actual power density to determine coverage areas and they are $$$$. If all you want is an indication of whether a change makes things better or worse as far as signal is concerned, then even the most basic cheap meter will work fine.

 

[groundwire]

I personally use bird fs meters, outstanding. But through the years I have found the old radio shack swr/fs meters to be the next best option. Fyi: get rid of the dumb little antenna and metal slot on the meter and replace it with a bnc, sma etc and a telescoping antenna with the same connector. Works awesome. Great sensitivity for what it is.

 

[jdchet]

I picked up one of these off Amazon. Price wasn't too bad.

We'll see how it works out!

JD

 

[Beetle]

The S-meter on portable/mobile receivers/transceivers is a prime candidate for use as a FS meter.

 

[jdchet]

Just curious....instead of keying down the radio, would running an antenna analyzer provide enough signal?

JD

 

[The DB]

The S-meter on portable/mobile receivers/transceivers is a prime candidate for use as a FS meter.

In a way I would say that this is true, as even though there is an s-meter standard, no radio manufacturer seems to follow said standard. I would also have to say, in my experience, an actual field strength meter, even a cheap one, is more sensitive than a typical s-meter, showing changes on their screen with a far smaller change in signal than a typical s-meter would show.

If you wanted to step it up a notch, its not much more expensive to get a nanoVNA, and plug a second antenna into the s21 port. If you use the nanoVNA Saver software on a laptop (that I use as opposed to the tiny screen on the device), you can get a field strength measurement readout that you can look at right next to all of the other tuning info that you want to see, and you can make adjustments to the antenna and see the changes in the field strength measurements, along with the changes with all of the other tuning settings you wish to see.


The DB