[Premium-Rx] Problem with my long-wire with balun 4:1

joseph.bozzer at skynet.be joseph.bozzer at skynet.be
Mon Apr 20 14:48:55 EDT 2020 

LW about 80m
Coax about 10m



Le 20 avr. 2020 à 8:40, Tom <n1bec at msn.com> a écrit :

How much distance between the FTDX5000 and the Balun? 
How long is the long wire?

Sent from my iPhone

On Apr 20, 2020, at 9:53 AM, "joseph.bozzer at skynet.be" <joseph.bozzer at skynet.be> wrote:

> My installation in the picture  below
> 
> I satisfied of my antenna and his balun
> Yesterday with 200w I connect a few American stations in CW .. 5000-6000Kms with a 5NN signal … Russian stations also
> Today Italy, Sweden and Italy always with 5NN signal
> 
> The SWR <1,5 in 80m and I’m not use the FTDX5000 internal ATU
> The SWR <2 in 40m
> The SWR = 5 in 20m and I use the FTDX5000 internal ATU
> 
> For a simple antenna as a long-wire I impressed
> For the listening I use a loop AL1530 and a IC-R9500 because the LW is too noise
> 
> 
> <antenne LF.jpg>
> 
> 
> 
> 
> Le 20 avr. 2020 à 6:27, Fernando <rumbek at gmail.com> a écrit :
> 
> I agree with Tom, but what puzzles me is that the system was apparently working perfectly fine before, and it started causing trouble all of a sudden.
> 
> It is important to differentiate here between counterpoise (sort of a return path for the radiated RF) and electrical ground. One thing cannot replace the other. A counterpoise is indeed a good thing to have in a LW installation. It can be laid out in many ways, straight, in a zigzag fashion, whatever fits our installation, really. Wires without counterpoise will work too, but in that case the RF will look for a return path which will often be the shield of the coax.
> The electrical ground has more to do with protection from static discharges etc. It is not the same as the counterpoise. And of course, the shorter the better as Tom points out. I am not sure what Joseph’s layout is like. For some reason I have imagined it as in the attached drawing (only that Joseph has no unun transformer (not a good idea this, for a transmitting end-fed wire), but a balun, which is indeed the correct solution.  
> 
> Personally, my ideal long wire setup consists of a random length of wire tilted from a high support (a tall tree, an antenna tower) down to a remote ATU. The ATU is placed just a few cm above the ground (to prevent the earth wire from radiating). The GND terminal of the ATU is connected to a good ground (for instance a series of copper rods driven into the soil) as well as to a few wires buried a few cm in the ground and forming like a fan under the LW, and at lest as long as the wire itself. Alternatively, instead of those buried radials one can very effectively use fewer, elevated ones, but these must be tuned (cut to the right length for each ham band we intend to use) and that often ends up being a cumbersome thing to do.
> 
> That is the kind of LW I successfully used for years in Zimbabwe (as Z21BB) and in Mali (as TZ6BB), with great signals on all bands, but then I was extremely lucky to have a QTH with a pretty big garden, which is not possible for many of us (indeed impossible where I am now).     
> 
> Well, if there is nothing broken in the set up, something simple to try first is to add (or to cut) a few cm to or off the wire, and see if that cures the problem somehow. But, at the end of the day the counterpoise would be a very good thing to have anyway, and it would improve the efficiency of that antenna system. The thing to do is to experiment and not to get discouraged.
> 
> 73
> 
> Fernando EA4BB
> 
> 
> <Unknown.jpg>
>    
> 
>> El 20 abr 2020, a las 16:15, Tom <n1bec at msn.com> escribió:
>> 
>> Hi Folks, 
>> 
>>  You really can't use the PL-259 as a ground because of the long distance it is from the Balun. 
>>  I suspect things worked on 80/40M because of the electrical length of the wire.
>>  With 20M, the electrical length of the coax becomes more significant. 
>>  I agree that your coax is radiating. 
>>  You may have an electrical length that is just right to cause severe radiation from the coax. 
>>  Without the body of the Balun going to ground, the coax will become the ground counterpoise and radiate.
>>  I'd be tempted to change to a dipole, and Fred with open wire feed, and see if that tunes add a real 4:1 Balun if needed just after the tuner.
>>  If you have to feed with coax, put the 4:1 Balun as close to the tuner as possible to keep down coax loss due to SWR mismatch.
>>  I have checked antennas with an antenna analyzer and had them check out fine, but fail miserably with high SWR under power.
>>  I found that with just the analyzer power, all was well, but I was not measuring high loss/mismatch due to poor ground, which was only seen under real power... A 160 Meter vertical was the poster boy for this... 3 radials = 3:1 SWR under real power.
>>  Adding about 20 more radials of various lengths gave me close to 1:1 SWR.
>>  Good Luck!
>> 
>> 73, -Tom N1BEC/7
>> 
>> Sent from my iPhone
>> 
>>> On Apr 20, 2020, at 6:41 AM, "joseph.bozzer at skynet.be" <joseph.bozzer at skynet.be> wrote:
>>> 
>>> Hi Fernando and Peter
>>> 
>>> I tested this :
>>> - the 50 ohms cable is not in short-circuit
>>> - the metal box of the ITA-MTFT is completly isolated... i can’t be used it earth counter-balanced
>>> - the earth cable of FTX5000 is good
>>> - the contact of this cable and earth stake is good
>>> 
>>> I think as you that’s a problem of cable sheath radiation 
>>> In looking this website, I would want to try to create a earth counter-balanced in putting to the earth the mass of PL259 at the output of the balun .. what do you think of that?
>>> 
>>> https://www.nonstopsystems.com/radio/frank_radio_antenna_multiband_end-fed.htm
>>> 
>>> 
>>> 
>>> 
>>> Le 20 avr. 2020 à 12:16, Fernando <rumbek at gmail.com> a écrit :
>>> 
>>> Dear George, I think these are very good points indeed.
>>> Otherwise I believe that the balun is already grounded through the coax’ shield, which is electrically connected (should be) to Joseph’s GND in the shack (I assume that the FTDX5000 chassis is connected to ground). In fact, something else to look into is the grounding scheme (1 - the integrity of the PL259 - SO239 connection at the balun, and 2 - the the grounding system at home is not interrupted). 
>>> 
>>> 73 de Fernando EA4BB 
>>> 
>>>> El 20 abr 2020, a las 11:02, George Georgevits <georgg at bigpond.net.au> escribió:
>>>> 
>>>> Hi Joseph,
>>>> 
>>>> Here is my 2 cents worth:
>>>> 
>>>> 1.    I agree with Fernando - it shows all the signs of cable sheath radiation
>>>> 2.    If you look at the ITA MTFT manufacturer's web site, says it is a 9:1 balun, NOT 4:1
>>>> 3.    9:1  is what I would expect for a long wire balun
>>>> 4.    You are quite right - there is no earth screw on the balun's metal body.
>>>> 5.    However, if you look at the recommended installation diagram, it is shown the metal balun body clamped to a vertical (metal) pole, which is presumably planted firmly in the ground.
>>>> 
>>>> See:
>>>> 
>>>> https://en.classicinternational.eu/antennas-assembly/antennas/home-made-antennas/ita-mtft/
>>>> 
>>>> My suggestion is -  try earthing the balun's metal case.
>>>> 
>>>> Cheers,
>>>> George Georgevits 
>>>> VK2KGG
>>>> 
>>>> 
>>>> -----Original Message-----
>>>> From: premium-rx-bounces at mailman.qth.net [mailto:premium-rx-bounces at mailman.qth.net] On Behalf Of joseph.bozzer at skynet.be
>>>> Sent: Monday, 20 April 2020 6:29 PM
>>>> To: Fernando
>>>> Cc: premium-rx at mailman.qth.net
>>>> Subject: Re: [Premium-Rx] Problem with my long-wire with balun 4:1
>>>> 
>>>> Hi Fernando
>>>> 
>>>> I explain you my installation
>>>> 
>>>> - My LW arrive to the balun 4:1 (ITA MTFT) on his alone screw .. no earth screw is provide by his manufacture … see his the picture
>>>> - the 50 ohms balun output cable arrive directly on my FTDX5000
>>>> - my FTDX5000 is connected at a big earth cable on a external earth stake
>>>> 
>>>> Joseph
>>>> 
>>>> 
>>>> 
>>>> 
>>>> Le 20 avr. 2020 à 10:26, Fernando <rumbek at gmail.com> a écrit :
>>>> 
>>>> Hi Joseph, 
>>>> 
>>>> My guess is your balun is not working as it should.
>>>> The LED lights at home lighting indicate that there is RF coming back through your coax, when you transmit. I believe that, in fact, RF is not getting past your balun and that you are radiating with your coax.  
>>>> In my view, there are several possibilities: mechanical problem (LW and balun are not making the necessary contact) or fried balun, which is rare but happens now and then (i.e. if at some point there has been a very heavy thunderstorm with lightning falling nearby).
>>>> 
>>>> Just my 2 cents. Good luck my friend, and best wishes to you and yours
>>>> 
>>>> 73
>>>> 
>>>> Fernando EA4BB
>>>> 
>>>> 
>>>> 
>>>>> El 20 abr 2020, a las 9:10, joseph.bozzer at skynet.be escribió:
>>>>> 
>>>>> I don’t understand what’s happened with my 80m long-wire since I installed a balun 4:1 on it
>>>>> 
>>>>> In 20 meter i’ve a SWR <1,5
>>>>> In 40 meter i’ve a SWR 1,5 =< 2 
>>>>> In 80 meter i’ve a SWR <5
>>>>> 
>>>>> With the ATU of my FTDX5000 I put all them to 0 but I have a big problem:
>>>>> - On 40 and 80m all is ok .. I’ve very good results in transmission
>>>>> - But on 20m it’s a disaster … some LED lamps in my house start to flash at the rate of my CW and the monitoring sound on my FTDX5000 becomes very raucous
>>>>> 
>>>>> It's impossible to use my Long-wire in 20m
>>>>> What's is happen? ... I remind you that without ATU the SWR is <1.5 over 20m
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> 
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>>>> 
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> 
> 
<antenne LF.jpg>

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