roof or ground 'height'?
 

hi

I have my antenna mounted on a apartment building roof, it's flat

it's about 20ft from the roof surface.


the roof/antenna is about 175ft above the ground

antenna 'rf' wise, i my antenna height measurement that i use, above
the ground or roof surface??

thanks

On Sun, 19 Jun 2005 18:11:20 GMT, ml wrote:
antenna 'rf' wise, i my antenna height measurement that i use, above
the ground or roof surface??

Hi Myles,

Both. For purposes of feeding it, the proximity of other conductors
and sources of loss, the antenna is as close as that 20' you offer.
On the other hand, for purposes of propagation, your antenna will act
like it is elevated 175'.

Your experience, compared to others, will fall somewhere in between.
Personally, I would think you have a very nice situation. If you seek
to improve it, it would only be in shades of a degree, not in leaps
nor bounds.

73's
Richard Clark, KB7QHC

On Sun, 19 Jun 2005 11:36:38 -0700, Richard Clark
wrote:
[snip]

If you seek
to improve it, it would only be in shades of a degree, not in leaps
nor bounds.


Certainly not near the edge of the roof anyway.

In article ,
Richard Clark wrote:

On Sun, 19 Jun 2005 18:11:20 GMT, ml wrote:
antenna 'rf' wise, i my antenna height measurement that i use, above
the ground or roof surface??

Hi Myles,

Both. For purposes of feeding it, the proximity of other conductors
and sources of loss, the antenna is as close as that 20' you offer.
On the other hand, for purposes of propagation, your antenna will act
like it is elevated 175'.

Your experience, compared to others, will fall somewhere in between.
Personally, I would think you have a very nice situation. If you seek
to improve it, it would only be in shades of a degree, not in leaps
nor bounds.

73's
Richard Clark, KB7QHC

dear Richard


thanks very much you set me straight.

I do ponder what i'd have to do (antenna wise) to get a significant
order of magnatude like perhas 200% ie 6db?

i guess going from dipole to a large beam would be significant in
comparasion

but what do you do when you want a bit more than a typical single beam
gives you? stack/co phase 2???

(naturally i am not counting amps of anykind here)

thanks all


and Rich , thanks

m

"ml" wrote in message
...
In article ,
Richard Clark wrote:

On Sun, 19 Jun 2005 18:11:20 GMT, ml wrote:
antenna 'rf' wise, i my antenna height measurement that i use, above
the ground or roof surface??

Hi Myles,

Both. For purposes of feeding it, the proximity of other conductors
and sources of loss, the antenna is as close as that 20' you offer.
On the other hand, for purposes of propagation, your antenna will act
like it is elevated 175'.

Your experience, compared to others, will fall somewhere in between.
Personally, I would think you have a very nice situation. If you seek
to improve it, it would only be in shades of a degree, not in leaps
nor bounds.

73's
Richard Clark, KB7QHC

dear Richard


thanks very much you set me straight.

I do ponder what i'd have to do (antenna wise) to get a significant
order of magnatude like perhas 200% ie 6db?

i guess going from dipole to a large beam would be significant in
comparasion

but what do you do when you want a bit more than a typical single beam
gives you? stack/co phase 2???

(naturally i am not counting amps of anykind here)

thanks all


and Rich , thanks

m

If you haven't already, you might want to check out what's happening at
Spiderbeam http://www.spiderbeam.net/ - - the construction techniques they
use appear to hold considerable promise. I'm particularly impressed with the
idea of incorporating a 40 meter dipole into their multiband Yagi array,
using a Delta-match fed wire connecting the 20m reflector and director
together so they act as capacitive hats to bring that short wire to
resonance at 7.05MHz. The details of the 40m modification are discussed in
the Spiderbeam Yahoo! group.

Chuck W6PKP

"ml" wrote in message
...
In article ,
Richard Clark wrote:

On Sun, 19 Jun 2005 18:11:20 GMT, ml wrote:
antenna 'rf' wise, i my antenna height measurement that i use, above
the ground or roof surface??

Hi Myles,

Both. For purposes of feeding it, the proximity of other conductors
and sources of loss, the antenna is as close as that 20' you offer.
On the other hand, for purposes of propagation, your antenna will act
like it is elevated 175'.

Your experience, compared to others, will fall somewhere in between.
Personally, I would think you have a very nice situation. If you seek
to improve it, it would only be in shades of a degree, not in leaps
nor bounds.

73's
Richard Clark, KB7QHC

dear Richard


thanks very much you set me straight.

I do ponder what i'd have to do (antenna wise) to get a significant
order of magnatude like perhas 200% ie 6db?

i guess going from dipole to a large beam would be significant in
comparasion

but what do you do when you want a bit more than a typical single beam
gives you? stack/co phase 2???

(naturally i am not counting amps of anykind here)


Actally, on HF, you will never have an antenna that will give you the boost
of an amplifier. I can think of any number of occasions when I was part of a
DX pileup with 100W; finally threw in the towel and fired up the amp. Guy
would come back to me on the first or second call.

Tam/WB2TT

thanks all


and Rich , thanks

m