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[G4YBP]

Hi, can anyone point me in the right direction to connect my 160metre dipole to the above tuner which is fed with open wire feeder. Someone has said one side to ground connector and other side to wire binding post - is this correct please.

thanks

Patrick

[KE6SLS]

Hello Patrick

Depending on how the dipole is made, it might work okay as you described.  If it simply won't match, then you will need a 1 to 1 or 4 to 1 balun & short patch coax to connect it to the balun which will work well.  My buddy has nearly the same setup for one of his balanced fed multiband wire antennas using the 4 to 1 and has no issues at all with it.

One quick note, if it starts raining, you will have repeat the process.  Totally normal for balanced feed systems.

73
Jaye

[G4YBP]

Hello Patrick

Depending on how the dipole is made, it might work okay as you described.  If it simply won't match, then you will need a 1 to 1 or 4 to 1 balun & short patch coax to connect it to the balun which will work well.  My buddy has nearly the same setup for one of his balanced fed multiband wire antennas using the 4 to 1 and has no issues at all with it.

One quick note, if it starts raining, you will have repeat the process.  Totally normal for balanced feed systems.

73
Jaye

Hi Jaye, I have not connected to feeder to the tuner yet as not sure how to. I have a home made un-balanced to balanced atu which is connected to the bottom of the feeder and works well.  Now I am 70 coils old I dont want to go outside to tune up.

[WB6BYU]

Balanced feedlines may be used with an MFJ-912 1.5 kW 4:1 balun connected to the MFJ-993BRT antenna output

Other external baluns will work, of course.

The best choice probably is a 1 : 1 current balun, although other types
may work well enough.

[KH6AQ]

The MFJ-993BRT (I have one) specified tuning range is 6-1600 ohms and a 1:1 balun may work just fine. For 160 meters a good choke is 17 turns of RG-58 on two stacked FT240-31 ferrite cores. The cores available at Amazon, Mouser and others. 

G3TXQ chokes   http://www.karinya.net/g3txq/chokes/

Stacked FT230-31 cores  http://www.karinya.net/g3txq/chokes/type31.jpg

MFJ-993BRT https://mfjenterprises.com/products/mfj-993brt

[WA3SKN]

I also think you should add a balun to your design near the tuner. And a Guanella type 4:1 will keep the static buildup down too.

-Mike.