On Tue, 18 Mar 2008 09:11:57 GMT, Owen Duffy wrote:

Alternatively, wind the wire onto a mandrill.

Or would that be a mandrel?


I've seen both spellings recommended in print, but winding wire onto a
mandrill will be far more entertaining.

PS: my (rather old) Concise Oxford Dictionary thinks a mandrill is a
"Large fierce West African baboon", fierce I guess when bound with wire.
It hasn't caught up with the alternative use for mandrel, well not by
1979.

The OED being old only excludes newer words - either way, mine shows
the spelling mandril.

73's
Richard Clark, KB7QHC

Ian White GM3SEK wrote:
Michael Coslo wrote:

David G. Nagel wrote:

Dave Heil wrote:


Well, there it is. I'm going to scrounge a "former" and a "sowing"
needle and get right to work.

Dave K8MN

Don't forget an 'apon'....



Can you guys tell us the correct way to spell coil former? It's
a bobbin made of insulating material upon which wire is wound.


Alternatively, wind the wire onto a mandrill.


Do you sedate the mandrill first? perhaps by clubbing it over the head
with a mandrel? or a mandril?

grin

http://en.wikipedia.org/wiki/Mandrill
http://en.wikipedia.org/wiki/Mandrel

Owen Duffy wrote:
Ian White GM3SEK wrote in news:U5VH68Pl733HFA
:

Owen Duffy wrote:
Ian White GM3SEK wrote in
:

Alternatively, wind the wire onto a mandrill.
Or would that be a mandrel?

I've seen both spellings recommended in print, but winding wire onto a
mandrill will be far more entertaining.

Ah, when popularity displaces correctness!


Ian was making a Pun, Owen! Visualize winding wire onto that Mandrill!
Yikes!


- 73 de Mike N3LI -

Mike wrote:
I can bear it no longer. We have Art the English educated antenna expert
who cannot write the English language,and now a Scot who doesn't know that a
Mandrill is a West African Baboon.
If you wind Art's wire on a Baboon it is going to get seriously ****ed off.
From an elderly Pom in Aus.


Dijya ever notice how after a few times of having to explain it, a joke
just isn't as funny?


Well, I got it, Ian.......



- 73 de Mike N3LI -

Richard Harrison wrote:

I`ve learned not to quarrel with Terman. So, I reread the page 929
quotation. I posted it correctly. He did say a loop antenna responds
much less to the electric induction field than does a simple wire
antenna of comparable intercept area.

Even Mandrills know better than to quarrel with Terman....


- 73 de Mike N3LI -

"Ian White GM3SEK" wrote in message
...
Owen Duffy wrote:
Ian White GM3SEK wrote in
:

Alternatively, wind the wire onto a mandrill.

Or would that be a mandrel?


I've seen both spellings recommended in print, but winding wire onto a
mandrill will be far more entertaining.


what i have seen is a 'coil form' is something that remains inside the coil
once it is complete. a 'coil former' is a removable frame or device that
you wind the coil on and then remove. These can be for large coils that are
then supported by something else, like tank coils in amps. Or for coils
that are then put on a core that is built separately, as in a high voltage
power transformer.

Michael Coslo wrote:
I can bear it no longer. We have Art the English educated antenna
expert who cannot write the English language,and now a Scot who
doesn't know that a Mandrill is a West African Baboon.
If you wind Art's wire on a Baboon it is going to get seriously
****ed off. From an elderly Pom in Aus.


Dijya ever notice how after a few times of having to explain it, a joke
just isn't as funny?


Well, I got it, Ian.......

Thank you, Mike! I was losing the will to live.


--

73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

Dave wrote:

"Ian White GM3SEK" wrote in message
...
Owen Duffy wrote:
Ian White GM3SEK wrote in
:

Alternatively, wind the wire onto a mandrill.

Or would that be a mandrel?


I've seen both spellings recommended in print, but winding wire onto a
mandrill will be far more entertaining.


OK, this time it's serious (well, mostly)...


The original meaning of "mandrel" seems to have been a rod-shaped tool,
onto which metal can be forged or glass can be mo(u)lded. The mandrel is
removed to leave a shaped cavity, and the mandrel can be used again.
This meaning is obviously very old, and would have crossed the Atlantic
with the Founding Fathers.

In the more recent context of coil winding, a mandrel is an object onto
which the wire can be wound. Again, the mandrel is always removed - it
is a tool, not part of the finished coil.

Some dictionaries note an alternative spelling, "mandril". This is an
old English dialect pronunciation, just like "chisil". (I don't know any
dialect-speaking blacksmiths, but can attest that "chisil" is still very
much alive.)

The confusion with "mandrill" comes from the fact that a convenient
mandrel of known size is the shank of... a drill.

The consequences of winding wire onto a mandrill - or indeed, onto a
ferret - are Nature's way of punishing engineers who can't spell.


Dave said:

what i have seen is a 'coil form' is something that remains inside the coil
once it is complete. a 'coil former' is a removable frame or device that
you wind the coil on and then remove. These can be for large coils that are
then supported by something else, like tank coils in amps. Or for coils
that are then put on a core that is built separately, as in a high voltage
power transformer.

That's completely different from British engineering usage. We don't use
"coil form" at all. "Coil former" almost always means something that
remains inside the completed coil. If it were meant to be removed, that
would have to be made clear from the context.


Cross-posted from rec.radio.amateur.etymology. We now return our antenna
readers to Prior Art.


--

73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

Art Unwin wrote:
On Mar 18, 12:26 pm, Michael Coslo wrote:
Roy Lewallen wrote:
Mike Coslo wrote:
On Fri, 14 Mar 2008 11:57:41 -0700, Roy Lewallen wrote:
Richard Harrison wrote:
Build a small scale model that can be tested indoors and report its
characteristics. Antennas are scaleable.
That's more easily said than done. One of the critical characteristics
of a small antenna is loss. And to correctly replicate loss in a scaled
antenna requires scaling the conductivity of the conductors as the
square root of the frequency. To scale to a higher frequency requires
that the conductivity be better than the original. Unless the original
is made from lead and the scale factor moderate, this wouldn't be
possible.
If what I suspect is true, would not the coax also need to be scaled?
Dunno. What do you suspect?
I suspect that the antenna is a tuned circuit on top of coax, and it
needs that coax to radiate effectively. So just scaling the antenna
wouldn't translate to the same results?

- 73 de Mike N3LI -

If you are familiar with computor programming then why not model it
instead of repeating over and over again this transmission line
radiation theory.?


It comes up in the conversation Art, I only rinse and repeat as necessary.

I'm still trying to wrap my mind around the antenna, I'm nowhere near
ready to model it. So as to not make any ignorant mistakes, the antenna
is counter-wound inductors, correct? and they are concurrently wound, as
in they sort of weave against each other? And this is a full wave
antenna? Do you use enameled wire, or what is the insulation? I'm
assuming that this might be important in regards to VF.

- 73 de Mike N3LI -

On Mar 19, 7:27 am, Michael Coslo wrote:
Art Unwin wrote:
On Mar 18, 12:26 pm, Michael Coslo wrote:
Roy Lewallen wrote:
Mike Coslo wrote:
On Fri, 14 Mar 2008 11:57:41 -0700, Roy Lewallen wrote:
Richard Harrison wrote:
Build a small scale model that can be tested indoors and report its
characteristics. Antennas are scaleable.
That's more easily said than done. One of the critical characteristics
of a small antenna is loss. And to correctly replicate loss in a scaled
antenna requires scaling the conductivity of the conductors as the
square root of the frequency. To scale to a higher frequency requires
that the conductivity be better than the original. Unless the original
is made from lead and the scale factor moderate, this wouldn't be
possible.
If what I suspect is true, would not the coax also need to be scaled?
Dunno. What do you suspect?
I suspect that the antenna is a tuned circuit on top of coax, and it
needs that coax to radiate effectively. So just scaling the antenna
wouldn't translate to the same results?

- 73 de Mike N3LI -

If you are familiar with computor programming then why not model it
instead of repeating over and over again this transmission line
radiation theory.?

It comes up in the conversation Art, I only rinse and repeat as necessary.

I'm still trying to wrap my mind around the antenna, I'm nowhere near
ready to model it. So as to not make any ignorant mistakes, the antenna
is counter-wound inductors, correct? and they are concurrently wound, as
in they sort of weave against each other? And this is a full wave
antenna? Do you use enameled wire, or what is the insulation? I'm
assuming that this might be important in regards to VF.

- 73 de Mike N3LI -

I think you should forget the whole idea. We have another expert
on line that can voutch for the fact that it is just a dummy load.
He joins the majority and I am only one,.....who actually has one no
less.!
Art