Topband: MFJ-1026 comments

[Bill Hohnstein K0HA]

N0AH wrote:

> but does "MFJ Wipe Out Interference"???????
> If anyone can attest to this unit, doing things in absolutes, as
> the ad reads- I'll state again what I stated earlier- your lucky-

Generalizations based on things other than testing the particular
product being discussed don't mean much.  I'm a MFJ-1026 user who
has no business relationship with MFJ, but I have performed many
tests with my MFJ-1026 in my 1.75 years of owning it.

> If you read the ad for this unit, the MFJ1026,  in their 1999 catalog
> on page 14, it states:
> 
> "Wipe Out All Types Of Noise"

Since static is dealt with later I'll only deal with line noise.
Yes, it can eliminate all types of point sources of line noise
very effectively.  If the noise is using a power line as an antenna
then not much reduction will occur however.

> Wipe Out Lightning Crashes

While it can "wipe out" 'A' lightning crash, or multiple ones to
the same point, I find it to be of limited value in reducing the
normal static here which arrives from a wide azimuth (this is what
I expected).

> Better Than Phased Antennas

Compared to the most common phased antennas used (those without
continually adjustable phase) the 1025/26 will do a much better
job of unwanted signal elimination.  This is after my having used
both.  With the 1025/26 the nulls can be moved to have maximum
reduction of the offending signal rather than having to hope that it's
magically located in one of your phased array nulls.  The unit is not
a magical device that will turn two bad antennas into one good antenna.
A little thought is needed in antenna choice.  Correct antenna choice
and placement may be needed for it to do an optimum job for you.
 
> Eliminate Unwanted Signals

I was surprised on how well it did this.  Due to the constant nature
of the AM broadcast signals I did tests on high frequency signals
in that region.  I tuned in a local signal.  I heard nothing else in
the background other than this signal.  With my MFJ-1026 I was able
to null out this local signal and then copy another station on the
same frequency that I didn't hear a bit of without the filter.
Potential multiple elevation/azimuth paths can sometimes reduce
the depth of its apparent nulling ability.  Again, it can't do magic
and having a reasonable antenna choice can make a large difference.

>  "Strong local ham overloading your sensitive receiver?  Cant copy
> your QSO?  Cast a deep null on him and literally take him out- you
> wont even know he is there"

That's close to the truth.  See the AM BCB remarks and limitations.

> Please...........if you null him out, do you really think you will
> hear your QSO too?

Certainly!  Unless the station that you're trying to copy is at the
same azimuth/elevation.

> If  his harmonic is on on top of you, and he is running full legal,
> and he is down the block- is this thing going to wipe him out?

That depends on the particulars...  Unless the harmonic is at an
illegal level or your antennas are abnormally close the unit will
help.  Again, the same no-magic, antenna limitations.
 
> Does the unit enhance reception? According to many low banders, it
> does-  and how nice it would be if it were advertised like this

Personally owning a business that sells RadioShack type electronics,
customer expectations and advertising claims make me grit my teeth
every day:
   "Why doesn't this $29.99 unit work as good a my neighbors?" (it cost
       $99.99)
   "Why should I pay $99.99 for this 100 watt RMS audio amplifier when
       store X has a brand Y 800 watt amplifier for $79.99" (it's 800
       watts super peak power--the fine print says 60 watts RMS)
   "Why should I buy this brand Z unit that says that it will remove
       some of the noise some of the time.  This brand AA unit implies
       that it will remove all of the noise all of the time?"
I don't have a good answer on how to handle these types of situations.
Some people are able to see through the advertising hype and make a
wise choice.  Some people just can't handle having a 100 watt RMS
amplifier while their friend has a 800 super-peak watt amplifier
(regardless of which is more accurate).  
A better product may not the choice of a customer if they're comparing
worse-case figures with best-case figures...

73,  Bill     K0HA



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