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[PajamaGuy]

It's Thanksgiving - the Hobby Shop is closed.  Then it dawned on me that I have a piece of coat-hanger in my desk drawer.  One of those brass-gold colored, fairly sturdy coat hangers.

Well GUESS WHAT!?!?!?!!?

It fits perfectly into a double-male F-Connector!!!!!!!!!!!!!!!

(Just saved $22)


Happy Thanksgiving!

[Brian H]

Looks neat.
One thing. Was it early when you got this thought? Isn't the F connector a double female? 

[dave w]

PJ Guy

Take some steel wool and polish up those threads a bit to get a better connection. I think it will make a difference.
BTW aren't you supposed to be carving the turkey? 

[axgupta1]

Some more ideas here:

http://www.cocoontech.com/index.php?showtopic=126
http://www.shed.com/tutor/mr26ant.html

[PajamaGuy]

Dave-W - thanks, I just grabbed the closest one - I'll use a new one for the project.

...Brian - it was dark-thirty, but when the threads are on the outside - it's MALE - when the threads are on the inside, it's FEMALE  

[steven r]

...Isn't the F connector a double female? 

...Brian - it was dark-thirty, but when the threads are on the outside - it's MALE - when the threads are on the inside, it's FEMALE  

Actually I've always heard what you used called a two ended female also.

The male connector is so named for the protruding straight center wire.

e.g. How would you name the slide on connectors that don't have screw threads? Transgender? 

[PajamaGuy]

axgupta1 -  And to the other gurus here:

http://www.cocoontech.com/index.php?showtopic=126

For the antenna pictured there.  What is the purpose of the 4 antennas on the corners?  If the bulkhead connector is properly seperating the center conductor from the grounding frame, how can the 4-downrods help reception - passive inductance?

[axgupta1]

My knowledge of antennas is limited to:
a) Bigger the better
b) Place them as high as possible
c) Place them in open air away from any possible source of interference...
 

Wish I had taken rf design in electrical engineering....

[steven r]

...What is the purpose of the 4 antennas on the corners?...

My antenna theory is weak but I've seen similar constructed antennas for ham radio. I'll try to remember to look it up in the ARRL handbook.

Ok looking through the handbook and doing a bit of Googling confirmed my memory that this is a form of ground plane antenna.
http://searchmobilecomputing.techtarget.com/sDefinition/0,,sid40_gci214329,00.html

[Brian H]

Depends I guess on who's description. I have always seen them called reverse of what you have called them.
Anyway the home made one you have given us was a good example of how one can be easily constructed.
Thanks again for your contribution.

Another slightly more complicated one with a set of four ground plane elements can be found here.
http://www.cocoontech.com/index.php?showtopic=126

[steven r]

This ad calls what he used a female to female.
http://www.summitsource.com/barrel-f-type-connector-female-to-female-gold-plated-f81-splice-coupler-2-pack-jointer-adapter-inline-coax-connector-double-female-in-line-audio-video-signal-component-plugs-p-7585.html

[dave w]

axgupta1 -  And to the other gurus here:

http://www.cocoontech.com/index.php?showtopic=126

For the antenna pictured there.  What is the purpose of the 4 antennas on the corners?  If the bulkhead connector is properly seperating the center conductor from the grounding frame, how can the 4-downrods help reception - passive inductance?

PJ
They form the "ground plane" for the 1/4 wave length antenna. 1/4 wave antennas need (or "work better with") a ground plane. 1/2 wave antennas do not.  The metal "L" mounting bracket on the WGL units forms a ground plane for the radiating element. If you do not intend on mounting the threaded portion of the female to female "F" connector    in a large metal bracket, then as a test, compare your range using a 9 inch coat hanger (1/4 wave) sans any ground plane, and a 18 inch coat hanger (1/2 wave). My bet is the 18 inch wire will give you greater range.

[PajamaGuy]

Brian & Steven - You guys are absolutely correct, anf I am wrong.  A search for "male f-connector" shows that the "union" that I thought was male, is actually a double femalw (as you said).  What's being connected is the center-wire; the 'male' end.  I learned something!  Thanks!

So, how was everyone's Turkey?

And Dave W, thanks for the Ground plane explaination.  So, in my attic where I'm not using a bracket, should I use an 18" piece?   (or 36")

[Brian H]

I believe the antenna from the WGL V572 I tried as a test. Uses the mounting bracket as a ground plane.

[dave w]

Brian & Steven - You guys are absolutely correct, anf I am wrong.  A search for "male f-connector" shows that the "union" that I thought was male, is actually a double femalw (as you said).  What's being connected is the center-wire; the 'male' end.  I learned something!  Thanks!

So, how was everyone's Turkey?

And Dave W, thanks for the Ground plane explaination.  So, in my attic where I'm not using a bracket, should I use an 18" piece?   (or 36")

18" if no ground.

If it is not difficult you might try a 9" rod also. My "cheap" antenna is nothing more than stripping the shield from the last 18 inches of the coax from the CM15A, leaving the center conductor as the 1/2 wave radiating element. I just ty-wrapped the tip of the center conductor as high on a vertical roofing stud as I could get. In other words, no female to female to female "F" connector or rod. I can hit the CM15 from the road...about 60 feet from the house. Actual range may be more, I just have not tried to find the limit.