One more note on the pennants. Based on my observations in the broadcast
band (actually changing ststion when switching directions), using a total of
70 feet in the loop, I wouldn't hesitate to go down to 40 or 50 foot loops
which might improve the directivity on 40 meters.
Gene / W2LU
----- Original Message -----
From: "Gene Fuller" <w2lu@rochester.rr.com>
To: <towertalk@contesting.com>
Sent: Thursday, February 02, 2012 1:47 PM
Subject: [TowerTalk] Fw: Fw: Flag Antenna Transformer
>
> ----- 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
>>>>>>>
>>>>>>>
>>>>>> _______________________________________________
>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> TowerTalk mailing list
>>>>>> TowerTalk@contesting.com
>>>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>>>
>>>>> _______________________________________________
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> TowerTalk mailing list
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>>>>
>>>> _______________________________________________
>>>>
>>>>
>>>>
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