this looks to be a 1:1 balun for TV

http://www.lincrad.co.nz/productorder.php?product_id=73&sub_cid=4&cat_name=%20Accessories&sub_cat_name=02%20%20Baluns

although scant details are given
Anyone have any thoughts on this balun or had previous experience with this manufacturer ?

I'm thinking about trying it for stacked CM4228s, my logic being that a pair of 4228's should have roughly the impedance of 4 times that of a CM4221.

Interesting....everything else on Lincrad's website is for TV Bands.
They don't have any specs for ANYTHING, including their extensive antenna line.

If shipping costs are excessive from New Zealand, maybe they can throw in some lamb chops....

PS: Study up some more re Stacking Antennas....the impedance does not quadruple.

Interesting....everything else on Lincrad's website is for TV Bands.
indeed, so one might assume that the 1:1 balun is for TV bands
They don't have any specs for ANYTHING, including their extensive antenna line.

PS: Study up some more re Stacking Antennas....the impedance does not quadruple.
indeed, but I did say that the impedance of 2 stacked 4228's might be 4 times that of a 4221 (not 4 times a 4228*, since a 4228 is more or less a pair of 4221's.
I've got the original 4228s, but for the new 4228HD, Ken Nist's 4228HD temporary page suggests
A 4228 is essentially two 300-ohm antennas connected in parallel, which would be 150 ohms. One would guess that the 4228 requires a 150-ohm to 75-ohm transformer, also called a 2:1 balun.
and I figured if you stacked 2 4228's, you'd be going from 150 to 75, and therefore a 1:1 balun might be in order

Stagger Stacking and Horizontal/Vertical Stacking Links are here:
http://www.digitalhome.ca/forum/showthread.php?p=963113

I decided to make an other coax balun this time for my FM yagi Winegard HD-6000.

I used 88 Mhz for the tuning frequency because I wanted to boost the channel on 88.1 MHz. It gave me a loop of about 1.346 meters with rg-59 foam.

I got a much better reception with my coax balun then the supplied balun and a Philips interior balun.

I decided to make an other coax balun this time for my FM yagi Winegard HD-6000 ... I got a much better reception with my coax balun then the supplied balun and a Philips interior balun.
Excellent. Did you use a hollowed-out 3-way splitter for this one?

Excellent. Did you use a hollowed-out 3-way splitter for this one?

No, I was on the roof with the Sony tuner and I was changing the baluns one by one.

I found out also that my homemade balun is not has good on some FM frequencies ( 95 MHz and up ) then the commercial baluns.

Compromise I guess, ;)

I did some tests today with an original 4228 mounted on my test tripod approx. 15 ft up. I tested a brand new CM 94444 balun versus a brand new Winegard TV-2900 balun. The Winegard balun was clearly superior.

I like how the Winegard has true twinlead to keep the wire spacing equal while the CM has separate wires which makes equal spacing difficult.

I also like the connecting lugs on the Winegard which give more connection surface versus the CM bare wires.

I had asked Tinlee about a high performance balun and they recommended to keep the twin lead wires the correct distance from each other as soon as possible from the feedpoint to maintain 300 ohm impedence. I also remember mlord's tests of his GH where the balun was the weakpoint and how maintaining the correct impedence from the feedpoint was critical.

I have no clue about RF and how it works so I'll leave that to the experts here. I have to resort to trial and error testing when I don't understand the mechanics.

I also realize I could have a bad 94444 or a really good TV-2009. I have a bunch more of each to continue testing with my trial and error approach. :D

Pictures of each balun are here:

http://www.digitalhome.ca/forum/album.php?albumid=211&pictureid=1412

I prefer the TV-2009 balun also except the waterproof boot that comes with it is too short when using Ideal compression F connectors.

I prefer the TV-2009 balun also except the waterproof boot that comes with it is too short when using Ideal compression F connectors.
That's a Good Thing, because it forces one to discard the water cup boot and use (much better) some tight wraps of electrical tape instead.

-ml

I like how the Winegard has true twinlead to keep the wire spacing equal while the CM has separate wires which makes equal spacing difficult.
I also like the connecting lugs on the Winegard which give more connection surface versus the CM bare wires.

on the downside, I've had the lugs come off some of those twinlead baluns on occasion

on the downside, I've had the lugs come off some of those twinlead baluns on occasion

Last week, I purchased a HD-6000 FM antenna and it came with one of those good balun. One of the lug broke immediately. I have to install an other lug.

Anyways, I am using a Homemade Coax Balun.

Does anyone know where to find a 2.5:1 balun made from two 120-ohm quarter-wave segments.

this balun is referred to in the modding of the 4228hd but I have been unable to locate one or any instructions on how to build one.

Odd-ball Ratio Baluns:
http://yagi-uda.com/coaxial_balun.php
http://standards.ieee.org/reading/ieee/ept/trans.pdf
http://www.highfrequencyelectronics.com/Archives/Nov04/HFE1104_Sevick.pdf

A Ham's Guide to RFI, Ferrites, Baluns and Audio Interfacing:
http://www.audiosystemsgroup.com/RFI-Ham.pdf
More re Ferrites and 1:1 Coax Choke Baluns:
http://www.geocities.com/ve2_azx/
And how to engineer an RF Transformer:
http://www.et.fh-trier.de/diplom/Team/berres/downloadbereich/Datenbl%C3%A4tter/PHILLIPS/ECO6907.pdf

Chudsmith: Have you look at Ken's new design harness?
The harness geometry:

http://www.hdtvprimer.com/ANTENNAS/CM4228ProposedHarness.gif

This is from ; http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html

Thanks holl ands and Xauto.

The reason I asked was to see if it was possible for me to improve my original CM4228, with the use of a 2.5:1 balun. From what I’ve read this may work better than the 4:1 balun.

Most of what holl ands provided is beyond my understanding. From what I did read I believe I would first need to learn more about my 4228 before I even started.

It’s clearly not as simple as ordering a 2.5:1 75-150 ohm balun online.

A tapered feed-line can transform from one impedance to another:
http://www.ittc.ku.edu/~jstiles/723/handouts/Tapered%20Lines.pdf
http://www.vias.org/radioanteng/rae_04_04_09.html
Simplest thing is to simply sketch out some rough lines in 4nec2's
Geometry Editor and what for improvements.
I couldn't find any good examples to show you other than this one:
http://www.academypublisher.com/ijrte/vol01/no03/ijrte0103277279.pdf

A Quarter-Wave (Q-Section) also can do an impedance transform:
http://www.qsl.net/w4sat/qtrwavtr.htm
http://www.hep.princeton.edu/~mcdonald/examples/EM/leeson_ee246_099.pdf
http://books.google.com/books?id=ivdWei8jb-cC&pg=PA414&lpg=PA414&dq=q+section+matching&source=bl&ots=FwvYtQxvKT&sig=C41hn0B9a-kOmX3KMN6DOE51Pqc&hl=en&ei=XJyWSq_dBYj8Me_0iPkN&sa=X&oi=book_result&ct=result&resnum=8#v=onepage&q=q%20section%20matching&f=false

PS: I'm not quite sure how you think you can improve on the CM4228's combining using a
2.5:1 Balun.....perhaps you could explain????
Since the 4-Bay is a good match to 300-ohm except at Low Freqs, changing from 4:1 to 2.5:1
would presumably cause mismatch over most of the band......

FYI: Old CM4228 and CM4221 (Actual vs Ken Nist's Demi-CM4228) 4nec2 files and analysis
can be found here:
http://imageevent.com/holl_ands/multibay

Hey holl ands .

Thanks but still beyond me.

I have no real reason to think the use of a 2:1 Balun will improve my signal I just wanted to give it a try and see. I first read about it in the same article Xauto provided the link for above.
( http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html )

the following is a quote from the same article.

Plot G uses a 2.5:1 balun made from two 120-ohm quarter-wave segments. The improvement is considerable. This is no surprise. A 4228 is essentially two 300-ohm antennas connected in parallel, which would be 150 ohms. One would guess that the 4228 requires a 150-ohm to 75-ohm transformer, also called a 2:1 balun..

I just thought I’d give it a try, as I’d rather not alter my original 4228 harness. Clearly it’s a little more involved than just whipping up a coax cable balun or ordering one online. I apologize if I’ve wasted your time I was just curious.

The problem with the unmodified CM4228 is wild fluctuations in impedance, so if you
improve one frequency band, another gets worse.

4nec2 sim results show that 300-ohm is "better" than 150 or 600-ohm loads, but NONE
of them truly match at the low freqs due to the extremely high REACTIVE component:
http://imageevent.com/holl_ands/multibay/8bayrefl/cm4228refl

The high REACTANCE problem is inherent in C-M's 4-Bays, rather than the feedline:
http://imageevent.com/holl_ands/multibay/4bayrefl
Note that 300-ohm is again the best load match for the CM4221....

Baluns can't fix REACTIVE load problems...a Matching Network is needed for that.
4nec2 has a built in Matching Network Function, "L/Pi/T Matching" under CALCULATE
but it only matches at one frequency and you'll have to do a Freq Sweep to see effect.
I haven't done it in a long time....might have to figure admittance for NT Card:
http://home.sandiego.edu/~ekim/e194rfs01/jwmatcher/matcher2.html
http://pdfserv.maxim-ic.com/en/an/AN742.pdf

PS: If you are using a Preamp, all this matching and Net Gain vs Raw Gain discussion
isn't nearly as important as with no Preamp and a long coax. And one way to "MOVE"
the standing wave to another frequency is to simply insert several different lengths
of coax until the null goes away on the channel(s) of interest.....

Thanks again holl ands.

Again most of the info you provided is far beyond my understanding. That said I do appreciate it and some of it may become clearer in time as I read up more.

I have been attempting to improve my signal to WUTV channel 14 in buffalo. My problem is by no means dire, I’m just messing around. Your insight above has planted new questions which I will save for the appropriate postings.

I constructed a coax balun designed for 473 MHz which did increase my signal strength to WUTV by 8%. The down side was that I lost other stations around 700 MHz .

I believe you have answered any questions I had about whether a 2:1 balun would help me and I think I’ll investigate other options.