----- Original Message -----
From: "Gene Fuller" <w2lu@rochester.rr.com>
To: "Richard Solomon" <dickw1ksz@gmail.com>
Sent: Thursday, February 02, 2012 1:41 PM
Subject: Re: [TowerTalk] Fw: Flag Antenna Transformer
> Hi Dick -
> If you're just using one at a time you don't have to worry about phasing
> just use relays to select one at a time.
> For each array I use a center pole (20 foot 4x4) where the four points are
> supported about 12 feet above the ground. I feed them at the point with
> about 8 feet of 450 ohm ladder line down to a box with relays and
> "matching" transformers.With the points all at the center post and using
> separate transformers for each antenna there are no common points until
> you get to the shield for the coax feed so there is a minimum of coupling
> between the antennas. Then four more posts to support the outer portion of
> the pennants. I use about 850 ohm half watt carbon terminating resistors
> supported on a small piece of fiberglass in the middle of the vertical
> outer wire, so the feed point looks like about 850 ohms which is matched
> down to about 75 ohms with little transformers. The second identical array
> is about 140 feet away, in my case with the N-S antennas in line so I run
> them broadside in phase for E or W or endfire 180 degrees out of phase for
> N or S. The only trick is keeping track of the phase which I did by
> tagging the transformer leads and double checking on a dual trace 'scope.
> I have the switching set up so I can listen to either array by itself or
> the pair. Although I can see some difference between a single pennant and
> a phased pair, certainly the largest difference is between my xmt
> antenna (a three bent vertical dipole parasitic array) and a single
> pennant. I think that the biggest difference between this type antenna and
> the beverage is that the beverages have a much narrower forward vertical
> lobe thus letting much less noise from the front of the antenna.
> When setting things up, keep in mind that the pennants, or flags, have a
> fairly broad forward lobe and a fairly deep and narrow null off the back.
> So setting it up so the null is where you want to reject become about as,
> or even more, important than where you want the maximum "gain".
> Good luck with your project.
> Gene / W2LU
>
> Original Message -----
> From: "Richard Solomon" <dickw1ksz@gmail.com>
> To: "Gene Fuller" <w2lu@rochester.rr.com>
> Sent: Thursday, February 02, 2012 11:59 AM
> Subject: Re: [TowerTalk] Fw: Flag Antenna Transformer
>
>
> I have two Pennants oriented NE and SW. Been thinking about adding two
> more. Can you tell me how you set up your 4 ? I didn't give any thought to
> phasing, just stuck a relay in a box to switch between the two.
>
> Thanks, 73, Dick, W1KSZ
> Vail, AZ
>
> On Thu, Feb 2, 2012 at 9:41 AM, Gene Fuller <w2lu@rochester.rr.com> wrote:
>> Al - No problem. Easy to do on such a busy thread.
>> I just like to encourage the use of flags and pennants. They certainly
>> are
>> very effective rx antennas. I've made a system using two four direction
>> pennant arrays, phased, using transformer matching and 75 ohm feed. It
>> works
>> great, definitely better than my tx antenna, but nothing like beverages
>> being used by guys within 100 miles of me.
>> Gene / W2LU
>>
>> ----- Original Message -----
>> From: "Al Kozakiewicz" <akozak@hourglass.com>
>> To: "Gene Fuller" <w2lu@rochester.rr.com>; <towertalk@contesting.com>
>> Sent: Thursday, February 02, 2012 10:27 AM
>> Subject: Re: [TowerTalk] Fw: Flag Antenna Transformer
>>
>>
>>> I'm sorry, I wasn't implying a mismatch as the culprit. I was commenting
>>> on an earlier remark.
>>>
>>> You were just the catalyst!
>>>
>>> Al
>>> AB2ZY
>>> ________________________________________
>>> From: towertalk-bounces@contesting.com
>>> [towertalk-bounces@contesting.com]
>>> On Behalf Of Gene Fuller [w2lu@rochester.rr.com]
>>> Sent: Thursday, February 02, 2012 10:21 AM
>>> To: towertalk@contesting.com
>>> Subject: [TowerTalk] Fw: Flag Antenna Transformer
>>>
>>> ----- Original Message -----
>>> From: "Gene Fuller" <w2lu@rochester.rr.com>
>>> To: "Al Kozakiewicz" <akozak@hourglass.com>
>>> Sent: Thursday, February 02, 2012 10:19 AM
>>> Subject: Re: [TowerTalk] Flag Antenna Transformer
>>>
>>>
>>>> Al -My guess is that it was just being completely over powered, not due
>>>> to
>>>> a mismatch. Gene / W2LU
>>>> ----- Original Message -----
>>>> From: "Al Kozakiewicz" <akozak@hourglass.com>
>>>> To: "Gene Fuller" <w2lu@rochester.rr.com>; "Pete Smith N4ZR"
>>>> <n4zr@contesting.com>; <towertalk@contesting.com>
>>>> Sent: Thursday, February 02, 2012 10:09 AM
>>>> Subject: RE: [TowerTalk] Flag Antenna Transformer
>>>>
>>>>
>>>> I constructed a K9AY initially using a Minicircuits device for the
>>>> transformer. I can state unequivocally that they are very delicate. My
>>>> K9AY is 100 feet away from a Butternut vertical. Tuning the AL-1500 up
>>>> on
>>>> 40m creates enough induced power to reliably blow that transformer
>>>> every
>>>> time.
>>>>
>>>> Al
>>>> AB2ZY
>>>>
>>>> ________________________________________
>>>> From: towertalk-bounces@contesting.com
>>>> [towertalk-bounces@contesting.com]
>>>> On Behalf Of Gene Fuller [w2lu@rochester.rr.com]
>>>> Sent: Thursday, February 02, 2012 10:06 AM
>>>> To: Pete Smith N4ZR; towertalk@contesting.com
>>>> Subject: Re: [TowerTalk] Flag Antenna Transformer
>>>>
>>>> Keep in mind that on 75/80 meters a pennant, flag, or ewe will only
>>>> have
>>>> a
>>>> "gain" of around -20dbi. so another db or two of loss due to miss match
>>>> will hardly be noticed and certainly isn't going to result in result in
>>>> damage due to heat or rf burns - or am I missing something ? However,
>>>> if
>>>> you're running a "phased" pair with transformer "matching" you would
>>>> want
>>>> to
>>>> keep track of the phasing.
>>>> Gene / W2LU
>>>>
>>>> ----- Original Message -----
>>>> From: "Pete Smith N4ZR" <n4zr@contesting.com>
>>>> To: <towertalk@contesting.com>
>>>> Sent: Thursday, February 02, 2012 6:30 AM
>>>> Subject: Re: [TowerTalk] Flag Antenna Transformer
>>>>
>>>>
>>>>> Is this necessarily true? I have a couple of transformers built by
>>>>> ON4UN. They use separate windings and a binocular core, and behave
>>>>> exactly as expected.
>>>>>
>>>>> 73, Pete N4ZR
>>>>> The World Contest Station Database, updated daily at
>>>>> www.conteststations.com
>>>>> The Reverse Beacon Network at http://reversebeacon.net, blog at
>>>>> reversebeacon.blogspot.com,
>>>>> spots at telnet.reversebeacon.net, port 7000 and
>>>>> arcluster.reversebeacon.net, port 7000
>>>>>
>>>>>
>>>>> On 2/1/2012 4:58 PM, Doug Ronald wrote:
>>>>>> You are getting these results because you wound a conventional
>>>>>> transformer
>>>>>> where a Transmission Line Transformer (TLT) is required. The core is
>>>>>> fine,
>>>>>> but twist the primary with the secondary using 12 turns and 3 turns.
>>>>>> Here
>>>>>> is
>>>>>> a reference to some theory on what you need:
>>>>>>
>>>>>> http://home.earthlink.net/~christrask/TraskTLTTutorial.pdf
>>>>>>
>>>>>> and the author (Chris Trask) has several other TLT articles on his
>>>>>> web
>>>>>> site
>>>>>> including precise winding tips.
>>>>>>
>>>>>> Here is another helpful link to the way your finished transformer
>>>>>> should
>>>>>> look:
>>>>>>
>>>>>> http://www.qsl.net/wa1ion/bev/bb_antenna_matching.pdf
>>>>>>
>>>>>> Hope that helps,
>>>>>>
>>>>>> -Doug, AE6SY
>>>>>>
>>>>>>
>>>>>>
>>>>>>> I have a flag antenna which has worked well for several years. I
>>>>>>> used
>>>>>>> a
>>>>>> Minicircuits T16-6 transformer to couple the ~800 ohm termination
>>>>>> resistance
>>>>>> of the antenna to 50 ohm line. Recently I decided to do some
>>>>>> upgrades,
>>>>>> so
>>>>>> I
>>>>>> followed the recommendations of many (here and elsewhere) and made a
>>>>>> matching transformer using an FT-140-43 core and 34:8 turns,
>>>>>> secondary
>>>>>> and
>>>>>> primary on opposite sides of the core. I didn't have any #28 wire so
>>>>>> I
>>>>>> used
>>>>>> #24. I tested this with a miniVNA, terminating the antenna side with
>>>>>> an
>>>>>> 800
>>>>>> ohm noninductive resistor. The impedance does not look right at all;
>>>>>> there
>>>>>> is a lot of inductive reactance and the resistive part starts at 125
>>>>>> ohms
>>>>>> and climbs steeply from 1.7 MHz. No on-the-air results yet.
>>>>>>
>>>>>>
>>>>>>
>>>>>> I'm wondering if this is right or not - measurements indicate the DIY
>>>>>> transformer is much worse than the T16-6 in terms of presenting a
>>>>>> good
>>>>>> match.
>>>>>>
>>>>>>
>>>>>>
>>>>>> This would not be the first case of theory saying it won't work but
>>>>>> practice
>>>>>> says it will - just looking for a reality check here. Seems to me
>>>>>> like
>>>>>> the
>>>>>> core material is all wrong...
>>>>>>
>>>>>>
>>>>>>
>>>>>> -Tony, K1KP
>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> TowerTalk mailing list
>>>>>> TowerTalk@contesting.com
>>>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>>>>
>>>>>>
>>>>> _______________________________________________
>>>>>
>>>>>
>>>>>
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>>>>
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