SWR METER

lunzac · Post by **lunzac** » Fri Apr 15, 2005 1:57 pm

hey everybody
just curious if you could give me your suggestion on a lower cost, entry level but still decent quality and easy to use SWR Meter that will work in the 460 range. also, any ideas on where i could buy one would be great too.

thanks

-zach

n3kvp · Post by **n3kvp** » Fri Apr 15, 2005 2:30 pm

Hi,
There very few low cost "SWR" meters on the market,( a few "ham" versions) most are very costly "Antenna Analyzers" the best bet is to get yourself a good watt meter, and measure forward and reflected power and the compute the SWR, although the Bird and Telewave meters come with a conversion chart to find the SWR.

kcbooboo · Post by **kcbooboo** » Fri Apr 15, 2005 3:53 pm

You can also check AES and Ham Radio Outlet, to name just a few. They sell SWR meters, but there aren't many that will do 450 MHz or so. Most are for the HF band 2-30 MHz and some will cover 150 MHz.

If you search eBay for "wattmeter" you'll find mainly Bird, but a few Telewave and Coaxial Dynamics units might show up. Expect to pay $150-$200 for a Bird 43 or Telewave 44A in good to very good condition. You will need elements for the Bird and CDI units, and these can cost $40-$70. Bird and CDI elements are interchangeable, and CDI's are cheaper, even if you buy them new. Each one covers a specific frequency and power range, so you'd need two (one for higher forward power, one for lower reflected power) to get an accurate VSWR value. Eventually you'll end up with a collection of elements, so you'll need a carrying case for the meter plus elements. They've really got you nailed once you "bite the bullet" and buy into this kind of equipment.

There are models from each manufacturer that don't need additional elements - one meter covers 20-1000 MHz and 5-500 watts. Expect to pay a bit more for one of these (the Telewave 44A can often be found for under $200 and that's a good buy).

Bob M.

Jim2121 · Post by **Jim2121** » Fri Apr 15, 2005 5:09 pm

you can also check out "Tucker Electronics" for swr & wattmeters..
and, "MFJ Electronics"
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depends on how much quality you need for whatever service

kb0nly · Post by **kb0nly** » Fri Apr 15, 2005 5:16 pm

Not to diss the ham gear, but its not always the best to use for commercial applications. Obviously since we are not normally concerned with anything above what we use.

The MFJ units that i have had over the years work great in the ham band, but have a varying degree of accuracy once you go beyond the intended bandsplit.

Better, though more costly, would be to buy an antenna analyzer and use that to adjust/check the antenna and feedline independent of having to transmit with the radio. The MFJ 269 is designed to cover up to 470 but at a cost of $359.95.

The MFJ 873 covers a range of 125-525 and 0-3000 watts. But at the cost of about $115.

440roadrunner · Post by **440roadrunner** » Fri Apr 15, 2005 6:24 pm

I disagree that antenna analyzers are necessarily "better." These analyzers can be problematic if one is trying to use them on a commercial site--with other transmitters nearby.

kb0nly · Post by **kb0nly** » Fri Apr 15, 2005 8:40 pm

440roadrunner wrote:I disagree that antenna analyzers are necessarily "better." These analyzers can be problematic if one is trying to use them on a commercial site--with other transmitters nearby.

Very true! However, the original poster never did specify the conditions at hand. I would assume perhaps a mobile install, so i just tossed that info out.

Glenn · Post by **Glenn** » Sat Apr 16, 2005 5:22 am

You can check out a few reviews on some SWR meters at http://www.eham.com that may help you decide on a purchase. Left side of the page under Resources are the Product Reviews.

RKG · Post by **RKG** » Sat Apr 16, 2005 11:11 am

I bought a Telewave 44A some years ago when I finally got frustrated at not having the one slug I needed, and I have been quite satisfied with it.

n3kvp · Post by **n3kvp** » Sat Apr 16, 2005 11:17 am

RKG wrote:I bought a Telewave 44A some years ago when I finally got frustrated at not having the one slug I needed, and I have been quite satisfied with it.

Yes, that is a good point, I had 2 Birds, and sold or traded them both for Telewaves for the same reason, out at a remote site and had to call another tech to bring me a different slug. As long as you do not need to go below 25MHz the Telewave is great.

Post by **Wowbagger** » Mon Apr 18, 2005 5:42 am

kb0nly wrote:Better, though more costly, would be to buy an antenna analyzer and use that to adjust/check the antenna and feedline independent of having to transmit with the radio.

440roadrunner wrote:I disagree that antenna analyzers are necessarily "better." These analyzers can be problematic if one is trying to use them on a commercial site--with other transmitters nearby.

And better still is to buy a directional coupler and a spectrum analyzer with tracking generator, with will work in the presense of other signal sources in the area.

And even better still is to buy a full vector network analyzer.

However, each of these steps costs quite a bit more money than the previous step. You have to make the call based upon the number of times you plan on doing this, the value of the sites you will be doing this on, and the amount of money you have on hand.

If you are working on low-value sites, or you have little money, going cheap (VSWR meter) may be the best overall solution for you.

RRrobby · Post by **RRrobby** » Mon Apr 18, 2005 5:48 am

Dayton is coming up. Happy hunting groung for bargains. I usually see a lot of nice bird 43's there-RRRobby

radio-link · Post by **radio-link** » Mon Apr 18, 2005 8:21 pm

[quote="WowbaggerAnd better still is to buy a directional coupler and a spectrum analyzer with tracking generator, with will work in the presense of other signal sources in the area.

And even better still is to buy a full vector network analyzer.
[/quote]

I have all these and some other toys available; usually I use the Rohde&Schwarz NAP, works fine, and usually with one head I can do all the normal range. Some dualband or glass mount antennas can be a PITA to adjust, then the Anritsu Sitemaster is a good choice, it combines the (antenna related) features of a network analyzer in the size of a normal wattmeter. It really can make your day, when fiddling with three alignment points to get proper SWR over a frequency range *g*

richyradio · Post by **richyradio** » Wed Apr 20, 2005 12:35 pm

Hi...I was wondering about the sitemaster....some people don't like them, but I wonder if they have any reference standard as to what is better or worse...they all seem to be the two-way radio types, with no experience w/ much better gear, so I cannot trust their opinion as to what they think is good...I think they mistakenly assume a couple hundred K of gear will magically do something better, when in reality it's up to you to know what is appropriate for what you are doing....I kinda' have an interest in the sitemaster....seems from the last post they serve a purpose in life....

radio-link · Post by **radio-link** » Thu Apr 21, 2005 1:16 am

richyradio wrote:Hi...I was wondering about the sitemaster....some people don't like them, but I wonder if they have any reference standard as to what is better or worse...they all seem to be the two-way radio types, with no experience w/ much better gear, so I cannot trust their opinion as to what they think is good...I think they mistakenly assume a couple hundred K of gear will magically do something better, when in reality it's up to you to know what is appropriate for what you are doing....I kinda' have an interest in the sitemaster....seems from the last post they serve a purpose in life....

Yes, they really do. We had to buy two of those for installation of GSM base antennas, to do the measurements of SWR and TDR, and we have started using them for all base antenna stuff, mainly police and on site communications. The customer is impressed by the printouts, and as an technician you can see with two looks that everything is OK with the whole system (transmission line and antenne), you can see if some dumbass has bent your cable - it really can save time and costs, even if those measurements are not demanded by the customer.

And when sitting in the trunk of a car, trying to adjust the dualband surveillance antenna (looking just like a FM antenna), the radio with the PTT in the front of the car, then you need only the tenth of the time with a sitemaster, compared to a normal wattmeter and the hassle with changing channels and keying the TX.

JAYMZ · Post by **JAYMZ** » Thu Apr 21, 2005 2:13 am

RRrobby wrote:Dayton is coming up. Happy hunting groung for bargains. I usually see a lot of nice bird 43's there-RRRobby

Some of the actual meters at dayton are decent.. but from experience trying to hunt down all the elements for my Bird 43 is that the elements some of the flea market vendors have are not always in the best shape and they are asking a lot of money for them. Generally about $15-$20 less than ordering it from Tessco or the like. I much rather wait until after Dayton and order a brand new element for that little price difference. Now... if the elements were about $35-$40 each.. then you have a bargain on your hands.

lunzac · Post by **lunzac** » Fri Apr 22, 2005 6:40 pm

thank you so much for all the advice and model numbers. i guess i know more but am also more confused. mainly about the differences between swr meters, watt meters, antenna tuners, antenna analyzers, ect. i looked at the MFJ 269 and really like it. i think i may spring for one, but just wanted to ask a couple questions first.
1. is there anything this antenna analyzer cant do that a watt meter, antenna tuner, or SWR meter could?
2. can i use this to check how much power my radio is sending out?

thanks

-zach

kcbooboo · Post by **kcbooboo** » Sat Apr 23, 2005 9:01 am

The MFJ269 will test mainly your antenna and tell you things about it, like the resonant frequency and impedance at various frequencies. You can't connect that to your radio to measure the power it's putting out.

A wattmeter will measure the power being transmitted by your radio. It should also tell you how much power is being reflected back by the antenna or load at the end of the coax. With these values, you can calculate the VSWR of the antenna system, but you can't figure out the actual impedance of the system.

VSWR or SWR meters will measure the percentage of reflected power coming back from the antenna or load, but not necessarily the actual amount of power in watts. Some meters have a calibrated scale that will indicate watts, but these are usually only accurate if the load is perfect, i.e. 50 ohms with no reactance. Trying to measure actual output power in watts with one of these meters, when connected to an antenna, will usually result in an inaccurate reading.

An antenna tuner is meant to connect between a transceiver (usually HF) and the antenna system which is usually less than optimal. It attempts to add inductance or capacitance to the system to present a more perfect load to the transmitter so you think things are working better. Some may have a VSWR meter built-in, and others might also try to indicate actual power in watts, but they often have the same problems as stand-alone VSWR meters.

You can calculate the VSWR or SWR of an antenna system with a wattmeter such as a Bird, CDI, or Telewave, since these will give you accurate readings of forward and reflected power, in watts, regardless of the antenna or load.

Vector analyzers and other complex test equipment have their places in life, like laboratories, but the average user doesn't need this much power. The antenna analyzer (MFJ269 etc) is nice to have in some situations, or if you will be doing a lot of antenna design and experimentation.

Depending on your current and expected future requirements and uses, I'd strongly recommend a Telewave 44A or Bird equivalent model as your first choice, followed by the Bird 43 and CDI equivalents, just because they're the most common, reliable, and familiar to most people. If you get deeper into antenna analysis, go buy a 269 as well. They both have their places, although I personally use the wattmeter a lot more often, especially for VHF and UHF situations.

Bob M.

lunzac · Post by **lunzac** » Sun Apr 24, 2005 8:31 am

hey bob
thank so for the clarification. that helps a lot. the one other question i had about a previous reply to my origional question was regarding antenna analyzers being inaccurate if there are other transmitters near by? what is that all about? are there similiar location concerns to keep in mind when using a watt meter?

-zach

kcbooboo · Post by **kcbooboo** » Sun Apr 24, 2005 9:44 am

The antenna analyzer (MFJ259 or 269) has a signal source and detector that allows it to measure the antenna parameters. A stronger signal coming from a nearby transmitter might throw off the detector and give you erroneous readings. I suspect that it would require several kw of power from a broadcast station that's perhaps 1/4 mile away or closer. Of course, another transmitter that happens to be on a frequency near the one you're trying to use to analyze an antenna system, will also cause problems.

A wattmeter is usually measuring power put out by a directly-connected transmitter. Its readings are not affected by strong nearby signals. They're quite insensitive to over-the-air signals. Having said that, I'm sure there are situations involving high-power paging equipment where you could see some power indication due to other on-site transmitters.

I think MFJ offers some kind of filtering device that's supposed to get rid of offending signals without affecting the readings from its own signal source. Most of that would be in the 30 MHz or lower frequency bands.

Bob M.

SWR METER

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