6 Meter long wire matching

[Tom Azlin, N4ZPT]

You only need a 6:1 to 9:1 if you are trying to match on harmonic 
related bands.  You slide the connection point away from the quarter 
wave point ~72 ohm point (usually toward the half wave point) to where 
you can get a compromise match of about 300-400 ohms on multiple bands.

73, Tom n4zpt

Frank Gentges wrote:
> Bob,
> 
> I am here looking at "Transmission Line Transformers" by W2FMI both the 
> original version and the second edition.  9:1 unbalanced to unbalanced 
> is covered but is HF with some roll off at 6 meters.  I think a tweak or 
> two could reduce the loss at the expense of 160 meters.
> 
> I will dig through my collection of cores and see if a simple 
> reproducible design can be made.  I have had good luck with these 
> ferrite transformers in the past.  Hopefully, this luck will continue 
> into the future.
> 
> Frank
> 
> 
> 
> 
> Robert Bruninga wrote:
>> For my long-wire 6m beam, I need to match my 50 ohm cable to
>> about 400 ohms or so.  I remember you can use 1/4 wave sections
>> in parallel to get impedances lower than readily availailable
>> coax, but also, you can "series" coax lines to get higher
>> impedances.  See attached drawing.
>>
>> In other words, two 70 ohm lines can give a section of 140 ohm
>> line.  I just cant remember how to hook them up (shields and
>> grounds), etc...
>>
>> Bob, WB4APR
>>
>>> -----Original Message-----
>>> From: Frank Gentges [mailto:metavox at earthlink.net] Sent: Thursday, 
>>> January 03, 2008 4:51 PM
>>> To: Tom Azlin, N4ZPT; Bob Bruninga; BOD AMRAD
>>> Subject: 6 Meter Radios and Projects
>>>
>>> Tom, Bob and all,
>>>
>>> It looks like a lot of good ideas are coming together on this.  I see 
>>> a lot of potential.  My lab has some good test equipment and I
>> can make
>>> some space so we can set up a test bed to try out some of this
>> stuff.
>>> It seems we need to have some sort of get-together and see how to 
>>> best proceed on various aspects.  Tacos some Saturday might work or 
>>> perhaps something more is needed.  Thoughts?
>>>
>>> Frank K0BRA
>>>
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> _______________________________________________
>>> Tacos mailing list
>>> Tacos at amrad.org
>>> http://www.amrad.org/mailman/listinfo/tacos
>