"Owen Duffy" wrote in message
...
On Sat, 24 Jun 2006 22:19:43 -0400, Dave wrote:

I get product not found!!

Is the URL complete?

Googling indicates that several domains are directed to this eCommerce
website, including jeanshobbies.com, amateurradio.org, buxomm.com,
commparts.com, packetradio.com.

Did someone say this guy is an Elmer? Looks like he runs a business
with a lot of front doors.

it appears that buxcomm is owned or operated by K4ABT. i have talked to him
several times.

he has a lot of history in the ham community.

Gravity

I get product not found!!

Is the URL complete?

it uses PHP and a link won't work.

Gravity

On Mon, 26 Jun 2006 00:08:48 GMT, Owen Duffy wrote:

Did someone say this guy is an Elmer? Looks like he runs a business
with a lot of front doors.

Hi Owen,

Buck wrote a column in CQ magazine for awhile a few years back and
abruptly left. Don't know the reason, but I did read some of his
writings and some were just plain nonsense. For example he advised his
readers that they needed to tune their transmission line if they
wanted the antenna to work properly. After a few like that I just
stopped reading his stuff.

By the looks of his antenna advertisements I made the right decision.

73,
Danny,
K6MHE

On Mon, 26 Jun 2006 00:49:09 GMT, "Frank's"
wrote:


"RMS power"). Incidentally 750 W into 4200 ohms represents
2.5 kV peak. If the balun is a real transformer it must be well
insulated.

.... and if it is a "voltage balun", a much higher flux level (~1300%)
than it would at 50 ohms.

Considering the information given in the product data, it leaves one
with doubts about the suitability of the recommended coax and the
supplied balun, and the performance of the entire system.

Owen
--

wrote:
The BuxComm Antenna Company sells what it calls an All Band Coax-fed
Dipole.

http://www.commparts.com/catalog/pro...ffad91005875fb


It consists of 135 ft. of wire, a balun at the center feed point, and
the RG 8X coax transmission line. I don't claim to know a whole lot
about antennas, but this configuration is contrary to everything that I
have read about feeding mutiband antennas. When I wrote to the company
with a question about this, I received a response from K4ABT, Buck
Rogers himself. He attached to his note a section from the ARRL Antenna
Book, which seems to indicate that coax should not be used with this
type of antenna if one wants to use it as a multibander. I have a lot
of respect for Buck, based on his years of Elmering a lot of us through
his articles. But this one has me stumped. Any input will be
appreciated.


My opinion would be that you'd be much better off if you want a single
wire antenna fed with coax going with one of the off center fed models.
the SWR is much better on many bands than the center fed model.

But if you must have a center fed model then you'll need to feed
it with open wire line of some sort .. coax just is not going to perform
well for you in a single wire all band dublet. the Losses on most bands
are not good.

73 Dave kc1di

wrote:
The BuxComm Antenna Company sells what it calls an All Band Coax-fed
Dipole.

http://www.commparts.com/catalog/pro...ffad91005875fb


It consists of 135 ft. of wire, a balun at the center feed point, and
the RG 8X coax transmission line.

A true coax fed "dipole" needs to see a 50 ohm load on
any of the bands to be used. Well, unless you like to lose
a lot of power on some bands. :/ So it would be better to
use an auto tuner at the feedpoint. It would be even better
to decide what bands you *really* intend to use, and run
dipole legs for each band in parallel. Spread wide apart
is better than stacking them on top of each other with
spreaders.
The antenna as they sell it is pretty micky mouse for an
"all band coax fed dipole". As one mentioned, the loss on
40m could be large if you feed with coax to a high Z load.
The antenna they sell would be best run using ladder line
all the way to a tuner, or tuned by length. Seems like you
say they mentioned this, but then why buy the uneeded
coax, choke, etc that you would end up discarding. ??
MK

Ooooo Saw the call and had to comment...

I have a 40M inverted Vee up around 35 ft. . I have had out of state
contacts on 75, 40(DX), 30(DX), 17, 15, 10 and 6. Is it a "good" antenna?

I wish I had better, but it "works". Do I think it is a great antenna? No.
Do I think it can be called efficient on the other bands? No. Do I think
it has lots of lobes on the higher frequencies? Yes. If I can hear them, I
can usually work them. OK by me... Do I have room for better? No.
I got much more than what I paid for $0.00. You can probably do better with
a "fan-type" dipole. I keep thinking I should at least add 75M wires and
20M wires. When I have time... . . . . . . . . . . .

The antenna in question is similar and just as inefficient on some bands and
has many lobes on others. It'll get you on the air if this is what you want
/ can afford.

Dave... I used to talk with KC9DI on 2M. We'd say the calls as fast as we
could, just to confuse the random listener...(:-)

73, Steve, K9DCI



"KC1DI" wrote in message
...
wrote:
The BuxComm Antenna Company sells what it calls an All Band Coax-fed
Dipole.


http://www.commparts.com/catalog/pro...ffad91005875fb


It consists of 135 ft. of wire, a balun at the center feed point, and
the RG 8X coax transmission line. I don't claim to know a whole lot
about antennas, but this configuration is contrary to everything that I
have read about feeding mutiband antennas. When I wrote to the company
with a question about this, I received a response from K4ABT, Buck
Rogers himself. He attached to his note a section from the ARRL Antenna
Book, which seems to indicate that coax should not be used with this
type of antenna if one wants to use it as a multibander. I have a lot
of respect for Buck, based on his years of Elmering a lot of us through
his articles. But this one has me stumped. Any input will be
appreciated.


My opinion would be that you'd be much better off if you want a single
wire antenna fed with coax going with one of the off center fed models.
the SWR is much better on many bands than the center fed model.

But if you must have a center fed model then you'll need to feed
it with open wire line of some sort .. coax just is not going to perform
well for you in a single wire all band dublet. the Losses on most bands
are not good.

73 Dave kc1di

Owen Duffy wrote:
. . .
Frank, in the absence of information on the balun, I did model it as
ideal, and that the load at the load end of the coax was 4200 ohms.
That is probably a reasonable assumption.

Perhaps the 4200 ohms is reasonable, but the assumption that the balun
is ideal when connected to that load impedance is most definitely not.
Any result you get when using that assumption is useless.

A real balun would not perfectly isolate the transmission line from
drive so influencing feed point impedance , and would probably
transform the real feed point impedance to something different to 4200
ohms, and so the line losses could be different (better or worse).

A real balun would do all those things, in addition to adding reactance
and, at that impedance level, loss.

. . .

Roy Lewallen, W7EL

wrote:
The BuxComm Antenna Company sells what it calls an All Band Coax-fed
Dipole.

http://www.commparts.com/catalog/pro...ffad91005875fb


It consists of 135 ft. of wire, a balun at the center feed point,

How did you conclude that the feed point is at the center? The lengths
of the sides are labeled only "L1" and "L2" on the drawing.

and
the RG 8X coax transmission line. I don't claim to know a whole lot
about antennas, but this configuration is contrary to everything that I
have read about feeding mutiband antennas. When I wrote to the company
with a question about this, I received a response from K4ABT, Buck
Rogers himself. He attached to his note a section from the ARRL Antenna
Book, which seems to indicate that coax should not be used with this
type of antenna if one wants to use it as a multibander. I have a lot
of respect for Buck, based on his years of Elmering a lot of us through
his articles. But this one has me stumped. Any input will be
appreciated.

I believe the antenna will be quite inefficient on some if not all
bands, either by accident (a balun which becomes lossy when confronted
with extreme impedances) or intent (a resistor inside the "balun"
container). If so, it's possible you'll get a reasonable match on all
bands, and nearly certain that you'll be able to talk to some people
when using it. But it also means that your signal will be considerably
weaker than it would be if you were using an efficient antenna.

Roy Lewallen, W7EL

Looking at the thing, I suspect that it is an OCF dipole. It isn't very
clear, but since they have a "L1" and an "L2", that gives us one clue.
Most center fed dipoles don't need an L1 and L2, because they assume
center fed, inherently 2 equal sides. Notice that they also say "this is
not a kit". That is a disclaimer that they put on their other OCF
antennas. Finally that 135 foot total length is typical of an OCF dipole.

Dis ting is quackin' like a big ol' OCF duck!

And as such it should be a serviceable antenna.

Funny that some people are dissing BuxComm on technical matters in this
case............ ;^)

- 73 de Mike KB3EIA -