Comparing my Starduster to my I-10K

[Marconi]

I just posted pictures of both antennas installed in the pictures area of this forum. RX signal reports are about the same with both antennas as best my TS570D's meter will respond without filters on. On TX the I-10K shows some to none improvement in signal to most stations, but it varies from station to station. Some station report equal TX on both antennas at 100 watts.

Have not DX'ed with this modified SD yet, but I am sure it will work fine there as well. If I can get some comparison reports with DX contacts I will add them here later.

Long-range local work so far, from 7.5 NW of downtown Houston to 260 miles over to Boerne, Texas northwest of San Antonio. Both antennas made 160 miles to Austin and Centerville, Texas as well. Port Arthur, Texas about 100 miles was worked during the early AM today. Talk anytime on either antenna 50-70 miles if I can hear them. Static is intermittent in this area during midday and conditions are only good early and usually late too. All contacts to the West were made at evening and to the East to Louisiana border during the early AM. Reports to the West could not tell a difference in signals between these two antennas as configured. Port Arthur reported a 1-S/unit increase using the I-10K.

Pictures available in PHOTOS section of this forum. Marconi's modified Starduster and I-10K

I did not tell you how they were elevated. They are both on 35' pushup poles. The I-10K is 35' to the base and the SD'r is 39' to the hub using a 9' mast in the antenna. So the I-10K is still 8' higher than the SD'r. My pushup pole has a problem coming out and I cannot get the last 5' of the bottom section to go up. So, I'm short of where I want to be.

 

[RoadWarrior]

Hi Marconi, Were they tested in 2 different locations
or the exact same location for both antennas???
Never mind...LOL... I checked out your pics. COOL!
I have to run one antenna here, then mount the other
antenna in the exact same location as only a few feet
here throws off the testing due to surrounding area.
What i usually end up doing is run each antenna for
a month or so to get the feel of it. Then change-ect. ect.
Looks like you did a good job on your Starduster!
Nice pics!

 

[2M Guy]

A Starduster is a 1/4 wave vertical. Radials with a downward angle to bring the impedance closer to 50 ohm. I'd hope Jays antenna would do better. Can't see how it wouldn't.
1 S-unit could be considered 6 db gain over the Starduster. Might be about right.

 

[RoadWarrior]

I think Marconi has the Starduster modified in some way.

 

[Farm Boy]

That 1 S unit in gain is equal to 6db voltage or 3db RF.
That means that the I-10K show an increase as if Marconi had doubled his output power.
Speaks very well for his modified Starduster.

 

[Marconi]

I appreciate the comments, but you boys must have a reading problem. You sighted-in on the 1-S/unit difference I noted to Pt Arthur, just one station. But you failed to notice the words:

On TX the I-10K shows some to none improvement in signal to most stations, but it varies from station to station. Some station report, equal TX on both antennas at 100 watts.

I did not get a conclusive result that either antenna was deficient in its ability to communicate at all even out to over 200 miles. Point is, I made contacts to all long range stations on both antennas.

Believe it or not, on the Marconi model which I developed testing on, I got the following results. Comparing my six ground plane Marconi and an Imax, both on ten foot masts, I got almost identical signal results. Of course on raising them both up to about 30' at the feed point, the Imax made 2-4 S/units of difference locally depending on location of transmitting stations. Here again, my test results were from my receive signals on my radio only. I made no comments on air about testing antennas. If the subject came up I would discuss results and they too were mixed, as one might surely expect from different radios.

This is all observations on my part and results may be different where you are, but I find little difference among many of our most popular 11 meter omni antennas when the overall height is held within 50' to 60' feet to the tip.