Does the thickness of the material used in antenna construction make any
difference to its performance? (Other than the obvious mechanical strength)
I have the option of using 3mm copper rod OR 15mm Copper pipe for 2m and
70cm 1/4 wave groundplanes.

73
Roger ZR3RC

Does the thickness of the material used in antenna construction make any
difference to its performance? (Other than the obvious mechanical strength)
I have the option of using 3mm copper rod OR 15mm Copper pipe for 2m and
70cm 1/4 wave groundplanes.

73
Roger ZR3RC



Yes, resonant frequency will change. To maintan the resonant frequency you need
to shorten the thicker diameter elements.

Yuri, K3BU

The bigger the pipe, the lower the 'Q' factor, hence you'll get wider
bandwidth.

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca

Does the thickness of the material used in antenna construction make any
difference to its performance? (Other than the obvious mechanical strength)
I have the option of using 3mm copper rod OR 15mm Copper pipe for 2m and
70cm 1/4 wave groundplanes.

73
Roger ZR3RC



Yes, resonant frequency will change. To maintan the resonant frequency you need
to shorten the thicker diameter elements.

Yuri, K3BU

The bigger the pipe, the lower the 'Q' factor, hence you'll get wider
bandwidth.

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca

Roger Conroy wrote:

Does the thickness of the material used in antenna construction make any
difference to its performance? (Other than the obvious mechanical strength)
I have the option of using 3mm copper rod OR 15mm Copper pipe for 2m and
70cm 1/4 wave groundplanes.

73
Roger ZR3RC

Use the pipe, all other conditions being equal.

Whether hollow or solid, the larger the diameter, the
better off you are for that antenna. It is not a
thickness issue. A solid 15 mm vs a hollow 15mm diameter
offers no advantage, RF wise. But in a 15mm diameter versus
a 3mm diameter comparison, the 15mm wins every time.

Use the pipe, all other conditions being equal.

Whether hollow or solid, the larger the diameter, the
better off you are for that antenna. It is not a
thickness issue. A solid 15 mm vs a hollow 15mm diameter
offers no advantage, RF wise. But in a 15mm diameter versus
a 3mm diameter comparison, the 15mm wins every time.

Assuming you shorten the elements and you want to sacrifice (small) gain
for bandwidth !!!

WB5UOI

"Hulen Smith" wrote in message
...


Use the pipe, all other conditions being equal.

Whether hollow or solid, the larger the diameter, the
better off you are for that antenna. It is not a
thickness issue. A solid 15 mm vs a hollow 15mm diameter
offers no advantage, RF wise. But in a 15mm diameter versus
a 3mm diameter comparison, the 15mm wins every time.

Assuming you shorten the elements and you want to sacrifice (small) gain
for bandwidth !!!

WB5UOI


Would you care to explain that? Where does shortening the elements come into
it?

I'm not really looking for gain - these antennas are meant to be "cloud
warmers",
want to connect with ISS and whatever sats are reachable. There may even
be balloon "sats" in my future!
I'm way too broke right now for a high gain, multi yagi, steerable, beam
assembly.

Now here comes the complication...

Would I keep the bandwidth advantage if I use 3mm for the radials and 15mm
for the radiator? The reason being easy costruction - solder the rods into
the chassis mounting holes on the SO239. Putting some kind of flange and
"nipple" on the 15mm pipe to get it into the socket centre-pin seems to be
not insurmountable.

73
Roger ZR3RC

"Hulen Smith" wrote in message
...


Use the pipe, all other conditions being equal.

Whether hollow or solid, the larger the diameter, the
better off you are for that antenna. It is not a
thickness issue. A solid 15 mm vs a hollow 15mm diameter
offers no advantage, RF wise. But in a 15mm diameter versus
a 3mm diameter comparison, the 15mm wins every time.

Assuming you shorten the elements and you want to sacrifice (small) gain
for bandwidth !!!

WB5UOI


Would you care to explain that? Where does shortening the elements come into
it?

I'm not really looking for gain - these antennas are meant to be "cloud
warmers",
want to connect with ISS and whatever sats are reachable. There may even
be balloon "sats" in my future!
I'm way too broke right now for a high gain, multi yagi, steerable, beam
assembly.

Now here comes the complication...

Would I keep the bandwidth advantage if I use 3mm for the radials and 15mm
for the radiator? The reason being easy costruction - solder the rods into
the chassis mounting holes on the SO239. Putting some kind of flange and
"nipple" on the 15mm pipe to get it into the socket centre-pin seems to be
not insurmountable.

73
Roger ZR3RC

Hulen Smith wrote:


Use the pipe, all other conditions being equal.

Whether hollow or solid, the larger the diameter, the
better off you are for that antenna. It is not a
thickness issue. A solid 15 mm vs a hollow 15mm diameter
offers no advantage, RF wise. But in a 15mm diameter versus
a 3mm diameter comparison, the 15mm wins every time.

Assuming you shorten the elements and you want to sacrifice (small) gain
for bandwidth !!!


What are you talking about? Numbers please.

WB5UOI