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Okay, TowerTalkians --
Here it is (I hope!) - the long awaited antenna analyzer post. Thanks to
everyone for their input. There is a lot of info here but makes for
interesting reading.
73, Steve K7LXC
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Re: [TowerTalk] Antenna analyzer comments wanted
To: <towertalk@contesting.com>
Date:=0998-01-25 23:22:34 EST
From:=09mwdink@eskimo.com (Michael Dinkelman)
To:=09K7LXC@aol.com (K7LXC)
At 02:18 PM 1/25/98 EST, you wrote:
>Hello, TowerTalkians --
>
> If you own or have used an MFJ, Autek, AEA or other antenna analyzer=
, >could you please give me your impressions. I own and use an MFJ 259 al=
l the
>time but would like your comments on how they work, susceptibility to RF=
,
ease of use, reliability, etc.
>
> This is research for an upcoming Up The Tower column. I will also pos=
t the
>responses to TowerTalk.
>
>73, Steve K7LXC
--
>
Yo Steve
=09I've had and used the RF-1 for over a year now. I prefer it
over the MFJ's (which the Club has). Takes some getting used to,
that meter on the MFJ is nice, but once I made up my mind I have
been happier with it.
=09I like its portability and versatility and cost. The hard
part is learning to adjust the frequency slowly. I've never had
any reliability problems except once when I had a dying battery
and didn't know it. Now, I have a test load (50-ohm resistor)
for checkout before every use.
Dink
Michael Dinkelman
mwdink@eskimo.co
---
To: <towertalk@contesting.com>
Date:=0998-01-26 13:55:13 EST
From:=09froberts@pe.net (Fred Roberts)
To:=09K7LXC@aol.com (K7LXC)
Steve-
Used both the older MFJ (external counter) and the AEA units briefly.
Was really impressed with the AEA as it produced an SWR curve for whateve=
r frequency band you wished. Of particular note, it did show when the SW=
R curve was unsymmetrical ... and that came as a surprise to me. My feel=
ing was the AEA gave you maximum information in a short time .... of cour=
se, it cost the most of any unit.
Also, noted that MFJ, AEA and Autek didn't provide exactly the same answe=
rs, but since the MFJ and AEA were borrowed, never had time to explore th=
is beyond a simple observation.
That's it...
73- Fred, W6TKV
--
From:=09rrossi@btv.ibm.com (Ronald D Rossi)
To:=09K7LXC@aol.com (K7LXC)
I use the Autek. I really like it.
Pluses:
Small
measures C and L direct (nice for hamfests!!)
considerably less expensive than MFJ
built solid
battery is easy to replace
rather accurate in all the comparisons I've done
has yet to fail on me
Minuses:
On/Off easy to bump (I have a neat fix for this included at the end.)
No analog meter (nice for finding minimums)
Course freq. adjust sometimes too course (you get used to it)
Fine freq. adjust sometimes too fine
Need to buy the VFH model to cover that band
> In a message dated 98-01-26 16:04:33 EST, you write:
>
> > measures C and L direct (nice for hamfests!!)
>
> Hi, Ron --
>
> Do you mean you use it to test things (like what?) before you buy =
them?
> Please elaborate.
Well for example what is the capacitance range of that unmarked air varia=
ble
capacitor? What's the minimum C? The rig is only good to something near 1=
000pF
(I would need to check this number), but that is fine for most of the var=
iables. I have used it for roller inductors, and chokes as well. You can =
get the impedance at a given frequency as well as the inductance value. A=
re these values what I'm looking for?
You can of course estimate the length of that roll of coax (in multiples =
of
1/2 or 1/4 wavelengths) as well as it's impedance (terminate with 50 Ohms=
...if
SWR is not around 1:1, then it must be 75 Ohm). You can do these tricks w=
ith the MFJ, but you have to carry it over your shoulder and look EXTRA g=
eeky (you're already geeky pulling out the test gear anyway, but at least=
it is not obvious, nor cumbersome).
It fits very well in a jacket pocket and with my power switch mod it won'=
t turn on accidentally.
--
73 de KK1L...Ron (rrossi@btv.ibm.com) <><
--------
Autek power switch fix (quote from my cq-contest list post)...
I came up with a very simple solution to one of the FEW things I find ann=
oying about the RF Analyst. You know how the on/off switch is SO easy to =
turn on accidentally? If you own one you do. Anyway I got tired of the th=
ing turning on in the pocket of my jacket.
My solution was to take a small (1/2 inch or so) piece of dense weather s=
trip
and put it right over the button (really more like a post). I am talking =
about
the closed cell foam with one sticky side, not the really spongy open cel=
l stuff. I first drilled a small hole to accommodate the post. The hole s=
hould be
just the right size to work best. I just twisted the drill bit in my fing=
ers, and did it before I removed the paper from the sticky side. Don't be=
silly and
chuck a bit up for this!! Also don't make the piece any shorter than 1/2"=
, as
the switch is actuated by side-to-side motion easily.
I had been trying to think up some sort of cover that I could flip up and=
out
of the way to turn the unit on. This is much simpler and very effective. =
I just had to tell someone!
--
To: <towertalk@contesting.com>
Date:=0998-01-25 15:09:50 EST
From:=09abowen@nettally.com (Bowen, Arlan)
To:=09K7LXC@AOL.COM
Steve: I wrote this originally in response to an inquiry on the reflector=
and saved it because I figured it would come up again. There is a lot mo=
re to the story, but only for those who do serious matching work. I made =
up a little universal L network. I take it out to the antenna, usually a =
vertical, and adjust for a perfect match. Then I measure the L and C comp=
onents and build up something that will handle power. Works slick. Much b=
etter than trying to guess the Xc or XL component required. Better than a=
noise bridge and much faster than the GR 916 boat anchor.
>>>I have the Autek RF 1, MFJ 259, the MFJ Noise Bridge and a GR 916 A, R=
F
Impedance bridge. Each of them have merit. The first 2, however, are prob=
ably the most useful and certainly quicker to use.
>>>
>>>The MFJ 259 will give you general information a lot faster and is quic=
ker, easier to use. It also goes up beyond 2 meters, so is useful at VHF.=
The Autek gives a bit more precision with digital readout, but not neces=
sarily accuracy. Accuracy is a function of calibration and a few other th=
ings. Generally speaking, you cannot read the analog resistance meter ver=
y closely on the MFJ. The meter on mine is not very precise either, when =
checking with known values. Autek appears to be very good in the range 10=
-100 ohms. I did not have any precision resistors to check the higher val=
ues.
>>>
>>>Take a typical problem. My pal is putting up a Beverage. He wants to k=
now if the old coax is OK to use on the low bands. First I put the MFJ on=
the open coax and find a low resistance "dip" around 3.2 mHz. Then I con=
nect the Autek and set it near that freq. I find a more precise dip that =
reads 7 ohms. Per the instruction sheets, I multiply the reading by a con=
stant and divide by the feedline impedance (50) and come up with 1.2 dB l=
oss (at that frequency). The analog meter on the MFJ would be hard to rea=
d at that low number. You would be looking for a few minutes longer to fi=
nd that impedance dip at 3.2 MHz with the Autek.
>>>
>>>Another typical problem. I want to know the SWR vs. frequency for a 5 =
band
quad before I crank it up to full height. I put the MFJ on the feeder and=
sweep the entire spectrum on all 5 bands, 20 thru 10M. I get ballpark SW=
R readings on all of them in about 5 minutes. With the Autek, you would b=
e at it somewhat longer as first you adjust the freq. dial to get to the =
band, then switch to SWR to get the reading. Adjustment of the frequency =
control is quite critical on the Autek. Lots of "kHz" with just a mini mo=
vement of the controls. Not bad once you get the hang of it.
>>>
>>>With MFJ, I can adjust the matching network on my 6 and 2M home brew b=
eams. Autek cannot do that. With MFJ, I can find quarter or half waveleng=
th of coax in just a few minutes. Autek takes more searching, but you get=
a more precise measurement if that is important. I actually use both. MF=
J to get in the ballpark. Autek for final value.
>
>There are many more examples. These are just ones that I have done recen=
tly.
>>>
>>>With Autek, I can measure capacitance and inductance with reasonable a=
ccuracy. I can adjust and check out Beverage step down transformers easil=
y
with it too. Ditto for coils needed in an L network for the low band ante=
nnas or any other similar application. I now know the value of all those =
mil surplus capacitors that I have accumulated over the years. Ditto for =
various variables that I have in the junk box.
>>>
>>>Bottom line? Try to get both. I don't think you will be sorry. Can onl=
y afford one? I guess I would go with Autek. Might be slower, but has a b=
it better resolution and more capability. You give up the 6 and 2 M bands=
, however. Autek only goes to about 32 mHz.
>>>
>>>Both will also act as low level RF generators, but the MFJ has a bit m=
ore output and an antenna port for that function. I can run my GR 916A im=
pedance bridge with the MFJ as an RF source. Can also be used as a precis=
ion dipper,
with the proper coils available from MFJ. The dipper function is quite in=
sensitive and not very useful.
>>>
>>>INK N4OO
>
---
To: <towertalk@contesting.com>
Date:=0998-01-25 20:50:41 EST
From:=09SavageBR
To:=09K7LXC
Hi Steve
If this sounds weird, it's because I am watching the Super-Bowl as I writ=
e.
I have used the MFJ-249 and now the 259 for several years. After 40 years=
in ham radio I think they are the best $$ value and most useful tool ava=
ilable. Of course my favorite pastime is playing with antennas of all kin=
ds. About 5 years ago I retired from a career as a microwave engineer des=
igning all kinds of antennas for satellites and spacecraft. During this t=
ime have used some of the most complex test equipment ever built but also=
the most expensive. I guess that is one of the reasons I enjoy the simpl=
icity, low cost and versatility of the 259 for use in ham applications.
What is great:
So many problems are confused due to the point of measurement. The portab=
ility of the 259 that allows measurements at the feed point of an antenna=
100 ft "Up The Tower" is very valuable. Also having a "plug in" direct =
reading grid dip meter in your pocket is very convenient.
Being able to measure complex impedance at the feed point with two simple=
readings from the 259 is also very valuable. I have a method that will p=
rovide complex Z by making two swr measurements. One measurement in the s=
tandard way and one measurement with a series resistor built in a connect=
or is all that is required.
I also use the 259 and a dummy load or a short to test all kinds of coax =
new and old for loss, quality of connector installation etc. It is probab=
ly the most useful trouble shooting tool in the shack when " something fu=
nny is going wrong" and the rig won't tune up right!
Think what we had to do to "create" an swr vs. freq. plot of an antenna f=
eed point before the age of the 249/259?
I have given both the 249 and the 259 rough treatment since they first ca=
me on the market without a failure
What is not so great:
Due to the basic operation, it is susceptible to stray RF radiation. If y=
our friendly CBer or another ham is operating near by or there is a stron=
g broadcast station in the neighborhood you can get some very weird readi=
ngs. I spent all one afternoon looking for a loose connection on an anten=
na because the swr APPARENTLY was intermittent. I finally realized my nei=
ghbor was testing and operating his CB radio in his camper. Every time he=
keyed the mic the 259 meter would peg looking like a lose wire in the wi=
nd. Boy did I feel stupid!!
Access to the battery holders is not very user friendly. Most folks subst=
itute an external battery. A battery "test" button would be nice for use =
before you start up the tower. Checking for the highest frequency availab=
le in the 170 MHz seems to be a pretty good indicator on mine. When the m=
ax freq. falls off the batteries are low.
The device would be more flexible if there was a 50 ohm-75 ohm switch. Th=
is should be rather easy for MFJ to implement. Since MFJ does not provide=
a schematic I am not sure. I wonder why they provide a parts list but no=
diagram?
A shoulder strap connected directly to the case-- not the carrying bag-- =
would be nice.
Most of my comments apply to all units you mentioned, but the cost and ea=
se of use of the 259 is hard to beat. No doubt my favorite and most used =
piece of test equipment.
There are probably a lot more comments but half time is over!
73s
Bruce AA4Z
--
To: <towertalk@contesting.com>
Date:=0998-01-25 22:18:57 EST
From:=09k6ll@juno.com
To:=09K7LXC@aol.com
I have the Autek, and like it. There are two nearby am BC stations, and t=
hey cause false readings on big antennas. In those cases, I front-end the=
Autek with an ICE mdl 402X am BC filter. Also, if the battery gets low, =
the unit will give false readings, with no other sign that the battery is=
low.
I like the fact that it measures high values of swr. This is useful for d=
etermining the loss in a piece of coax. The little manual that comes with=
the unit is very helpful and informative.
Dave Hachadorian, K6LL
Yuma, AZ
K6LL@juno.com
---
To: <towertalk@contesting.com>
Date:=0998-01-25 22:52:01 EST
From:=09ab5tv@ix.netcom.com (Madison Jones)
Reply-to:=09ab5tv@ix.netcom.com
To:=09K7LXC@aol.com (K7LXC)
I have used my MFJ-259 for about 18 months. It works very well for my pu=
rposes, though the cheesy battery boxes are WORTHLESS. I solved my probl=
em of having them break at inappropriate times and places with the result=
ing loss of use by using Velcro to attach a 2 ah gel cell of approximatel=
y the same width and depth of the analyzer case.
Prior to obtaining the '259, I used the prior model (one-meter showing
SWR, as I recall) and liked it. There was a very interesting article in =
73 magazine a couple of months ago on how to modify the bottom-of-the-lin=
e MFJ (no bells, no whistles and almost no cost) so it will give all the =
features of the '259. Looked like a very satisfactory meter at modest co=
st ($100+or-).
Last year at XA5T, we used the AEA model in getting a number of antennas =
up on the same tower. It has some features which the MFJ doesn't, and to=
ld us our 160 wire was being de-tuned by the Cushcraft 40-2cd. Don't kno=
w if it really was, but we did move the 40-2cd to another tower under a T=
H6, where all worked well. The MFJ did not show the conflict, so we don'=
t know if it was all necessary.
Don't know about the Autek, except to say the frequency dialer is far eas=
ier to set/read than the MFJ, which needs a vernier or something to desen=
sitize it a little. It's also much smaller, and therefore somewhat less =
bulky to haul up and down the tower.
Regards,
Madison
w5mj
--
From:=09tgstewart@pepco.com
To:=09K7LXC@AOL.COM
I own both an AEA and the Autek.
The AEA is very nice when tuning up antennas, it's big advantage being th=
e overall "picture" of the antenna with it's frequency scanning capabilit=
y. It is, however, very susceptible to external RF on the lower bands whi=
ch can disturb your readings and in severe cases even cause the "out-of-l=
ock" indicator to come on, making it useless. In most cases, it's a very=
useful tool.
I haven't used the Autek much but it seems quite handy, being a very smal=
l
package. Physically it's a little delicate so treat it with care. I hav=
en't noticed any RF problems, though I'm not sure I've given it a chance =
to exhibit any.
73, TY K3MM
--
From:=09k4sb@mindspring.com (K4SB)
Reply-to:=09k4sb@mindspring.com
To:=09K7LXC@aol.com (K7LXC)
Well, I guess you didn't like my joke. By the way, 1 paw Ed is now 2 paw
Ed again. They took the pins out Tuesday.
I have used the MFJ's since they first came out, and have had no problems=
.
No overload, no false readings. My major problem with them was to convinc=
e myself they tell the truth. Each time, every time. They are exceedingly=
accurate for cutting 1/4 wave lines, etc, and the other features. BTW, I=
own 3 of them. ( 1 is permanently mounted in the truck for the screwdriv=
er ant with a 2 way coax switch. Switch to the MFJ and hit the switch on =
the screwdriver, and you're at 1:1 PDQ.
I would give you my amplifier if you pointed a gun at me, but you'd have =
to shoot to get my MFJ.
73 Ed
--
To: <towertalk@contesting.com>
Date:=0998-01-25 16:18:31 EST
From:=09froberts@pe.net (Fred Roberts)
To:=09K7LXC@aol.com (K7LXC)
Steve-
I use the Autek unit and find it is particularly handy when travelling be=
cause it is so very small. The course/fine frequency adjusting process i=
s touchy, but it works fine. It did the job for me when installing wire =
antennas in the field.
When I received the unit from Autek, it had an internal short that was re=
medied by sending it back to Autek ... I wondered if they had done a fina=
l checkout. Also, the power switch is a pushbutton switch and sensitive =
to being turned on in a suitcase ... so I have found it necessary to remo=
ved the battery when packing it.
73-
Fred Roberts, W6TKV
--
To: <towertalk@contesting.com>
Date:=0998-01-25 17:14:23 EST
From:=09dx@traverse.com (Barry Martz K8BK)
Reply-to:=09dx@traverse.com
To:=09K7LXC@aol.com (K7LXC)
Hi Steve.
I have the Autek RF-1. It works fine but is not anywhere near as easy to=
use at the MFJ. The all digital is TOUGH to use compared to the analog =
meters. It is very RF sensitive. I took it with me on a trip to a local=
island to set up a vertical (putting tuner at antenna base) and another =
station was transmitting on another band about 90 feet away and it would =
not work at all. I bet the MFJ would react the same but that is my exper=
ience. For the few times you actually
use it per month, the Autek works fine. If I were using it more often, I=
would get rid of it and spend the few extra bucks and get the MFJ!
7 3 de Barry/K8Bk
--
From:=09w0etc@ix.netcom.com (Larry Lindblom)
To:=09K7LXC@AOL.COM (K7LXC)
Steve:
The area just east of Des Moines, IA is broadcast station alley. Multipl=
e big time FM stations and several AM stations including WH0 (50 kW into =
a half Franklin antenna). I'm 5 miles east of the city and n0ni is 15 mi=
les east. We've used both his MFJ & my Autek at both locations. The MFJ=
is highly susceptible due to strong BCI, the Autek doesn't seem to be ef=
fected as much as the MFJ by the BCI.
My 25 cents worth (2 cents adjusted for inflation)
73 from IA (that's where the fat hogs grow-hey, something has to eat all =
the tall corn)
Larry L. w0etc
--
From:=09k4oj@ij.net (k4oj)
Reply-to:=09k4oj@ij.net
To:=09K7LXC@AOL.COM (K7LXC)
yo, Steve
We use the Autek - but it is a royal pain in the ass - the damn know is s=
o sensitive to tuning you barely touch it and you move freq. 100KHz...loo=
king
back I kinda wished we had gone with the MFJ, I stayed away because of th=
e
MFJ reputation...
The Autek is also RF susceptible.... it is not much good at my Dad's plac=
e on VLF since there is AM BC nearby...
later
oj
--
From:=09Earl_Dery@mindlink.bc.ca (Earl Dery)
To:=09K7LXC@AOL.COM
Hi Again Steve,
I own an earlier version MFJ (207) an Autek, and recently got the AEA.
Each one seems to have their own strengths and weakness. The MFJ seems to=
generally be quite reliable as does the Autek, however at times the Aute=
k will read a bit different than the MFJ. I can't yet make a much of a c=
omment on the AEA as I just got it for Xmas and haven't really had time t=
o get to know it. I had got the AEA primarily because one could store the=
ir SWR plots and print them out for reference (not done yet).
The size of the Autek sure is nice when you carry it up the tower.
73 Earl VE7IN
--
From:=09davidg@primenet.com (David Gilbert)
To:=09K7LXC@aol.com (K7LXC)
Hi, Steve.
I've owned an Autek RF-1 for about two years, and think it is a great pie=
ce of gear. I've tried it against a variety of known passive loads (RLC =
combinations), and it has always checked out. When I've used it on anten=
nas, I sometimes get readings I don't fully understand, but most times th=
ey make sense after some experimentation. I've come to trust the little =
bugger pretty well.
If the SWR is not too high (say less than 5:1), you can use a little form=
ula to get actual R and X values instead of just Z. I've found that it d=
oes indeed work.
I've never had the occasion to operate it in high RF ambients, so can't s=
peak to that. The battery life is pretty marginal, and I wish it didn't =
cycle through the bands with a push-button -- all it takes is an inadvert=
ent touch to send you to an unwanted frequency. But those are about the=
only downsides to what is otherwise a pretty slick little tool for us an=
tenna geeks.
73,
Dave AB7E
---
To: <towertalk@contesting.com>
Date:=0997-03-20 09:12:39 EST
From:=09yo3ctk@alltrom.ro (Mihail Mateescu)
Sender:=09owner-towertalk@contesting.com
To:=09towertalk@contesting.com
This is the summary of all responses I received to my query (names
withheld). Thank you all for your efforts.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I own the Autek RF-1 because it also does uH that I believe are easier, t=
han,
if not possible with, the MFJ-259. The MFJ-259 discount price is $195. Fr=
om R&L Electronics in OH, which is lowest I have seen.
Of course, the RF-1 is $129.95 direct from AUTEK.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I just bought a MFJ 259 and I love it! It is GREAT!
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
The MFJ is much easier to use and read.
I have the Autek. It works great but it tougher to use because it has on=
e meter and it's digital. The analog metering of the MFJ makes it much e=
asier to use.
Price: the Autek beats it hands down.
Size: Autek wins.
Ease of use: MFJ
If you are in no hurry when using it, for the money, the Autek does the s=
ame thing for less but the MFJ is easier to use.
I bought the Autek because the analyzer is something I will NOT be using =
everyday. I figure for the amount of times I will be using it, I can tak=
e a bit more time, and save the money for other things.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Buy the Autek. I've owned the AEA, Autek, and MFJ.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I've used the MFJ 259 many times (I borrow it from a fellow ham. hi) and =
it works super!! I can tune just about any antenna to resonance @ impedan=
ce within about 2-2 kHz. It's very easy to use and IMHO is about the only=
piece of equipment they make which works reliably. (Other than my old MF=
J 204B bridge/Ramsey frequency counter). If you can get a 259 which works=
the first time, you won't be disappointed in its capabilities. (MFJ usua=
lly has a 50% failure rate on almost any item you buy). As far as the Aut=
ek RF-1 goes, I've never heard of anyone using one, so cant help you ther=
e.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I just bought a MFJ-259 but haven't used it yet. I have been thinking of =
buying
the Autek RF1 , in addition to the MFJ-259, as I believe the Autek offers=
features that the MFJ-259 unit doesn't have, and, the MFJ-259 has featur=
es that the Autek doesn't have.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Direct your question directly to John Broznahan, W0UN, "Mr Antenna!" He
Has bought and used them all.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I have the MFJ antenna analyzer - it works like a charm. It makes it so e=
asy to get your dipoles, beams etc. resonant you'll wonder how you ever g=
ot along without one.
Be sure to get the model with the digital frequency counter, not the one =
with the analog dial.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I have the MFJ-259. It works great. Don't know how I lived without one =
for so long. Not sure if you can find the AEA version since they went ou=
t of business. For the money the 259 does everything I need. It is grea=
t to know exactly where the antenna is tuned and what affect you are havi=
ng on it while trying to tune it.
I usually avoid MFJ but I am happy so far.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
The MFJ seems to be the most popular. The other popular one is the AEA, =
but I think I recall seeing that AEA was sold and things are a little con=
fused until the new owners settle things down. I think the MFJ costs a l=
ittle less than the AEA too. People who have used both have said that ea=
ch is better at some things and the best approach is to have one of each!
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=09 I have used an Autek RF-1 for a bit over a year. I've used other
Ham's MFJ 259 at various times too.
=09In my opinion the Autek RF-1 is the better value for the money but
the MFJ might be considered easier to use in some cases. The controls on =
the MFJ are definitely easier to use, as the "fine" tuning control on the=
RF-1 is too fast and I seem to spend time "tweaking" to get just the fre=
quency I want for a test. So for quick SWR tests the MFJ seems much easie=
r to me. Another nice thing about the MFJ is being able to look at the SW=
R and frequency at the same time. On the RF-1 you must alternate these re=
adings although there is a trivial setting to get automatic alternation.
=09The RF-1 will make some kinds of measurements that the MFJ will not,
allowing you to create your own custom inductors and capacitors tested at=
the
frequency of interest (but with accuracy to just get you into the right r=
ange prior to trimming) On the other hand I think the MFJ can be arranged=
to function as a crude dip meter with an add-on accessory and this isn't=
available with the RF-1.
=09Another thing is that the RF-1 is very compact. I've spent a lot of t=
ime hanging off the top of a ladder with the RF-1 stuck right into an ant=
enna's feedpoint and I can't say I'd like to try that with the MFJ. I've =
even hooked up my RF-1 to an antenna, hoisted it up, and read the display=
with binoculars. This is conceivable with the MFJ (especially somebody e=
lse's <g>) but the extra weight would make me nervous.
=09The RF-1 uses up its battery pretty quickly. I get perhaps 3-4 months =
of use from one 9 volt battery by turning it off whenever I'm not using i=
t for more than a few seconds.
=09Overall, the RF-1 has drastically improved my ability to figure out wh=
at is going on with my antennas. I've also switched it in place of my tra=
nsceiver to work out tuner settings without having to transmit.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
We use then all, including the AEA.
The one I use most often is the MFJ. The Autek is somewhat difficult in t=
hat sweeping an antenna is done via pushing frequency selector buttons an=
d looking at a digital readout. The analog meters on the MFJ are much bet=
ter and the
frequency is always available, unlike the Autek, which must switch the di=
splay.
A word of caution - all of these meters have a common problem. When used =
in the
presence of fairly strong RF fields, they will not indicate the antenna u=
nder
test properly. This is especially evident on 80, 160 and even 40 when the=
antenna being tested is within several miles of an AM broadcast station.=
The
devices all use low level RF energy going to the antenna and measure the =
return
loss. Unfortunately, the front ends of the devices are necessarily broadb=
anded.
This means they pick up everything and oftentimes this "everything" is mo=
re energy than the device generates. The result is a VSWR reading that wi=
ll never
approach 1:1, or approach whatever the antenna really is.
I recently have been continuing tuning on my 3 element 80 Zagi and have t=
o do it
when the AM stations change directions, otherwise the measurements are un=
usable.
Had a fellow trying to tune a 40M Yagi once. He called me, said the VSWR =
was
1.5:1 and I suggested a small change. He called me back about 30 minutes =
later
and said it was now 10:1! Guess what - the AM broadcast station a few mil=
es away
had just made the evening antenna direction change.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I have both the Autek RF-1 and the MFJ-259 I bought the RF-1 first and wa=
s not impressed I recently got the 259, A much better instrument. The con=
trols on the RF-1 are much too small and reactive a small turn on the tun=
e control sends you from one end of a band to the other, making it very h=
ard to use with any amount of accuracy. The MFJ-259 is bigger and the con=
trols are easier to use, also you see both the SWR and resistance at the =
same time not so with the RF-1. The 259 also has a frequency counter, but=
it is also almost twice the price I spent the extra money because I was =
not impressed at all with the RF-1.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I cast my vote strongly of the MFJ-259. It is an extremely versatile pie=
ce of equipment and seems (by all accounts I've heard from all that own o=
ne) to be very accurate. Also, MFJ gives very good customer service.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
I find the Autek the most cost-effective solution. It does everything th=
e others will do, and more, and it's cheaper!
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
You might look into the AEA graphical antenna analyzers that actually dis=
play the actual SWR curve on the LCD. AEA was recently purchased by Temp=
o Research Corporation in Vista, CA. Their telephone number is 760-598-8=
900. They are in a state of transition now, but they should be able to d=
eliver new analyzers within a couple months.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
73 de Mike, YO3CTK
--
To: <towertalk@contesting.com>
Date:=0998-01-26 17:49:37 EST
From:=09on7nq@glo.be (Danny MEES)
To:=09K7LXC@aol.com (K7LXC)
Hello Steve..
I have an MFJ259 here and been using it for about 3 years now. Tuned my 8=
0m vertical, 1/4 WL slopers for 80m and my quad with it. Worked fine for =
me but do not have any experience with the other products such as the AEA=
or Autek.
A few things I noticed while using it are:
1) check the batteries frequently or make sure the PS is stable.
This could lead to mis-readings.
2) Use RF beads
3) a bit un-handy for tower climbing.
Again the MFJ259 has been a very handy tool for me!
73 es GL with the article in CQ Contest.
ON7NQ Danny
----
To: <towertalk@contesting.com>
Date:=0998-01-26 22:20:50 EST
From:=09avidham@sojourn.com (Roger C. Stimson)
To:=09k7lxc@AOL.Com
Steve,
I find the MFJ 259 one of the best antenna accessories to ever come=
down the pike. True, it is not a lab instrument. True, it is a pain in=
the ass to change the batteries and it does perform erratically when the=
batteries get low. True it is vulnerable to high RF environments.
BUT...I find it very useful for two everyday ham activities: (1) I u=
se it to tune my NYE Viking tuner off the air and (2) I use it to check m=
y antennas and feedlines throughout the winter months when snow and ice d=
o strange things to feedpoint impedance. I have overcome the battery pro=
blem by keeping one of my MFJ 259s hooked up to a 13.8 vdc power supply. =
It is always ready to go and works perfectly. I am just 1/2 mile from t=
wo TV towers--one to my north and one to my east--and do not experience a=
ny problems with their emissions, RF or otherwise. I have the two Autek =
SWR analyzers and use them when I am on the towers. Their compact size m=
akes them ideal for quick checks when high off the ground.
Next to my safety belt, tool bag and tools, the SWR analyzers are th=
is hams best friends.
73 Roger K8RS
--
Have uses some of the others but not enough to give a good evaluation...
Likes of AEA:
1) seem to be very accurate
2)really like the graph to see exactly where antenna resonance
3)easy to use and see while up the tower
Don't like about AEA:
1)Large and bulky to carry up the tower-- no real way to secure--- I use =
a small nylon rope to hold to my belt...
2) unit has been sent back for repairs twice because of "high RF environm=
ent"--
what ever that means---- cost me about $100 per trip
Hope that helps Steve... whatever device u need one of them to test inste=
ad of the constant up/down... I guess I'm getting too old but limit mysel=
f to 3 trips in any one day up the towers... most of my towers are at lea=
st 150 ft
73
bud-k4isv
--
>Hi Steve, I have been using the AEA SWR121 for over four years now and t=
hink is an invaluable piece of equipment for antenna work. I find it to =
be very well constructed, accurate, stable and dependable. I have checke=
d its stability and accuracy with my FT-1000 and it is every bit as good =
as the 1000 in these categories. SWR accuracy, it follows what I get wit=
h the Bird watt meter.
That being said I think its best features are the ability to see the freq=
uency response of the band in question, the graphical representation is s=
uperb. Another feature that I use it for is checking out old coaxial cab=
le or new for that matter. All my coax is checked for attenuation with t=
he unit prior to installing it. When I first received the unit I checked=
a 300 foot run first using a bird and dummy load at the distant end. Ca=
lculated the attenuation based on the loss and then used the SWR121 to te=
st the same length of coax at the same freq. Results were less than a te=
nth of a dB difference.
I was having a real bad time with the elevated radials of my 160m antenna=
.
I used the length that both Elnec and AO suggested. However using the SW=
R121 installed between two radials as you would a dipole and seeing the b=
and I was able to adjust their length, and what a difference that made.
I don't think you could find an easier piece of gear to use. Simply punc=
h in what you want on the keyboard and you are presented with a nice pict=
ure, and you know what they say about a picture.
The push of two buttons lets you know the status of your battery supply a=
nd calibration.
Two negative comments, was at a friends home who lives near a broadcast s=
tation and while checking his 160m antenna the results were erratic due t=
o RFI from the broadcast station.
At first it appears a bit pricey but the time it has saved me. All my mo=
nobanders, coax runs, and wire antennas have and are periodically checked=
with the unit. The above may sound like a sales pitch Steve, but trust =
me I am in no way connected with the mfr. I just trust the unit as it has=
never failed me. 73 Pete N4KW
--
From:=09dick.green@valley.net (Dick Green)
Reply-to:=09dick.green@valley.net (Dick Green)
To:=09K7LXC@AOL.COM (K7LXC.)
Hi Steve,
I've used the MFJ 259 and the Autek.
The analog meter on the MFJ is a more natural and intuitive way to find S=
WR dips than the digital display on the Autek. However, that's about the =
only good thing I can say about the MFJ.
The tuning resolution on the MFJ frequency counter is so tight that it's =
really tough to pinpoint the exact frequency of the dip. The Autek is muc=
h better in this regard, and also has a fine tuning knob for even better =
resolution. The Autek tends to agree with my rig much more often than the=
MFJ.
The MFJ is big and awkward while the Autek is small and very handy. I don=
't go up the tower (tubular crank-up), but I'd imagine that the Autek wou=
ld be much more convenient up there for folks like you.
The MFJ burns up batteries much quicker than the Autek.
The MFJ's resistance meter is only accurate at resonance. The Autek shows=
impedance, capacitance, and inductance, regardless of resonance.
Both units are reasonably well documented, but the Autek manual gives muc=
h more detailed technical information.
Hope this helps.
73, Dick, WC1M
--
I have 2 antenna analyzers: the MFJ-259 and the Autek RF-1.
The MFJ has one feature the Autek doesn't have - an external input to t=
he frequency counter (which also has more digits of resolution). But tha=
t's about all it has over the Autek. The Autek, on the other hand, is le=
ss expensive, has digital readout for everything, is more accurate, works=
down to 1.2 MHz (vs. 1.75MHz for the MFJ) and costs $110.00 less. Both =
units are essentially SWR meters and "V/I" meters. The Autek has the adv=
antage of being more accurate and can measure pure capacitances and induc=
tances directly (it measures Xc or Xl and Freq. and then does the math to=
determine C or L). The Autek is only the size of a pack of cigarettes.
The MFJ has one major problem that caused me to buy the Autek a couple =
of months later. It showed much higher SWR than actually existed on the =
Mosley PRO-96 I was putting up. It caused a couple weeks of consternatio=
n until I talked to Mosley and was told about how the MFJ couldn't handle=
the complex periodic impedance presented by multiband antennas. I also =
had trouble getting low, stable SWR readings at the base of my 160-meter =
shunt-fed (L-network) tower. The SWR would bounce all around between 2.5:=
1 and 4:1. Yet when I fed the tower with my XCVR the SWR on the XCVR wou=
ld read 1.2:1. I have not had these problems with the Autek. The Autek'=
s readings are accurate enough so that you can actually calculate R+jX fr=
om SWR and Z using the formula they give in the manual. I did have one p=
roblem with the Autek - a bad solder joint on one of the boards. But I w=
as able to touch up all the connections and eliminate the problem.
So for my money the Autek is the clear winner.
73, Wayne - W1QC >>
--part0_886351245_boundary--
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