On Wed, 19 Nov 2008 22:45:19 GMT, Rich Grise wrote:

But I've been searching the web for some weeks now, and I can't
seem to find any kind of formula, except there was this program
I downloaded - LPDA.EXE, which runs on DOS. Unfortunately, it's
in Russian or Polish or Uzbekistani - one of those East Yurp
languages. Here's a screen snap:
http://mysite.verizon.net/richgrise/...rog-Output.gif

Which I went through pretty much by-guess-and-by-gosh - can
anybody read that stuff?

Hi Rich,

Someone else has already provided the translation, so that will take
care of some of the wholes in data entry and reading.

There are a lot of factors I don't know about, like "Tau", and
all of the specific designs on the web are flat - something is
telling me I want one of those pyramid-shaped ones, but I really
don't know the difference (between that and flat) - it's probably
something to do with bandwidth or F/B ratio or whatever.

Tau is related to the shape of what you call the pyramid, or more
actually to the angle of the taper. This defines the smoothness of
matching across the span of frequencies you entered into the program.
As you can see, it also relates to the available gain. Another
correlative is it also relates to its length. All of these things are
trade-offs that lend to the rule of choosing what you want most and
giving up on the rest.

I note elsewhere that you wanted something about 1 foot long. There
is a Tau that will give you this boom length, and you got it on the
first guess.

So, how do I pursue this? It'd be nice to have a program that will
calculate the whole thing for me, but am I dreaming? If I want to
send myself to Log-Periodic School, where should I start?

You should start building what your screen shot gave you IF that is
the span of frequency you need (already questioned by other
correspondents).

73's
Richard Clark, KB7QHC

On Wed, 19 Nov 2008 22:53:28 -0800, Richard Clark wrote:
On Wed, 19 Nov 2008 22:45:19 GMT, Rich Grise wrote:

But I've been searching the web for some weeks now, and I can't seem to
find any kind of formula, except there was this program I downloaded -
LPDA.EXE, which runs on DOS. Unfortunately, it's in Russian or Polish or
Uzbekistani - one of those East Yurp languages. Here's a screen snap:
http://mysite.verizon.net/richgrise/...rog-Output.gif

Which I went through pretty much by-guess-and-by-gosh - can anybody read
that stuff?

Someone else has already provided the translation, so that will take care
of some of the wholes in data entry and reading.

There are a lot of factors I don't know about, like "Tau", and all of the
specific designs on the web are flat - something is telling me I want one
of those pyramid-shaped ones, but I really don't know the difference
(between that and flat) - it's probably something to do with bandwidth or
F/B ratio or whatever.

Tau is related to the shape of what you call the pyramid, or more actually
to the angle of the taper. This defines the smoothness of matching across
the span of frequencies you entered into the program. As you can see, it
also relates to the available gain. Another correlative is it also
relates to its length. All of these things are trade-offs that lend to
the rule of choosing what you want most and giving up on the rest.

I note elsewhere that you wanted something about 1 foot long. There is a
Tau that will give you this boom length, and you got it on the first
guess.

So, how do I pursue this? It'd be nice to have a program that will
calculate the whole thing for me, but am I dreaming? If I want to send
myself to Log-Periodic School, where should I start?

You should start building what your screen shot gave you IF that is the
span of frequency you need (already questioned by other correspondents).

73's

"Best Regardses"? ;-)

Anyway, thanks for this - I'm feeling a lot better about this project now
thanks to your help and that guy that translated it for me (forgot the
name, but he knows who he is - Thanks Again!);

I might even start cutting wire[1] and soldering this weekend! ;-)

Thanks!
Rich

[1] GTAW (Gas Tungsten Arc Welding) filler rod, with some coppery-
colored coating that solders even better than copper, about .030 dia.,
and as stiff as piano wire.

Rich Grise wrote:
On Wed, 19 Nov 2008 22:53:28 -0800, Richard Clark wrote:
. . .
73's

"Best Regardses"? ;-)

No, that's "Best Regards's". It's the possessive, not plural, form of
"Best Regards". I think the grammar is part of the same dialect as the
verb "destinate" (as in "I've just destinated"), but you'd have to ask
Richard about that -- he's the one with the English Lit degree.

Roy Lewallen, W7EL

On Thu, 20 Nov 2008 15:35:53 -0800, Roy Lewallen wrote:
Rich Grise wrote:
On Wed, 19 Nov 2008 22:53:28 -0800, Richard Clark wrote:
. . .
73's

"Best Regardses"? ;-)

No, that's "Best Regards's". It's the possessive, not plural, form of
"Best Regards". I think the grammar is part of the same dialect as the
verb "destinate" (as in "I've just destinated"), but you'd have to ask
Richard about that -- he's the one with the English Lit degree.


I read it in a QST or so back in the 1960's. :-)

Thanks!
Rich
ex-WN0GJS

Roy Lewallen wrote:
Rich Grise wrote:
On Wed, 19 Nov 2008 22:53:28 -0800, Richard Clark wrote:
. . .
73's

"Best Regardses"? ;-)

No, that's "Best Regards's". It's the possessive, not plural, form of
"Best Regards". I think the grammar is part of the same dialect as the
verb "destinate" (as in "I've just destinated"), but you'd have to ask
Richard about that -- he's the one with the English Lit degree.

My Webster's unabridged dictionary gives the following
examples of the correct way to pluralize numbers.

"figure 8's", "the 1890's", "the 20's"

73 is a number that stands for "Best Regards"

73's would be "Lots of Best Regards".
--
73, Cecil http://www.w5dxp.com

Cecil Moore wrote:

...
My Webster's unabridged dictionary gives the following
examples of the correct way to pluralize numbers.

"figure 8's", "the 1890's", "the 20's"

73 is a number that stands for "Best Regards"

73's would be "Lots of Best Regards".

A friend of mine is a dispatcher for police/fire/ambulance/etc., in my
area. Her 10 code often requires her to use the "10-73" from this ten
code--which is a "smoke report."

So, thanks for clarifying this for me. I simply took the 73's on many
of the posts sigs as a sign they were "blowing smoke" (actually, "Lots
of smoke!" :-) ), and giving me fair warning! straight-face

Regards,
JS

On Wed, 19 Nov 2008 22:53:28 -0800, Richard Clark wrote:

You should start building what your screen shot gave you IF that is the
span of frequency you need (already questioned by other correspondents).

Apparently I'll only need up to ch. 52; have to look up the carrier freq.
on that.

Ch. 14 = 470-476 MHz
Ch. 83 = 884-890 MHz I think.

Now all I need to do is the algebra. ;-)

52 - 14 = 38
38 * 6 = 228
228 + 470 = 698
698 + 6 = 704

Cheers!
Rich