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#1
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*************************************
All things being equal: 1.Top loaded antennas perform marginally better than base loaded 2.Taller antennas (less loading coil) perform better than shorter 3. Thicker antennas perform marginally better than thinner. 4. More conductive antenna stock makes a marginal difference over less conductive antenna stock. 5. A higher antenna mount works better than a lower mount. 6. A free and clear antenna mount works better than an obstructed one. 7. A more substantial RF ground works better than a minimal ground. This is true but I have seen installations that were actually OVERGROUNDED and hurt performance. 8. A vertical antenna performs better than a diagonal (windblown). Number 5, 6, & 8 are the most important factors in the performance of an antenna. Now if any one could come up with a formula that includes all of these factors then we would be able to answer your question. There is no formula. However we can say this. The best mobile antenna is a thick stiff nine foot whip that is silver coated and mounted on top of the roof with multiple radial grounding points. No one is going to use the antenna above in the real word, so one might draw the conclusion that in the real world we might substitute a 102" stainless whip for the best real world performance. WRONG. The 102" is made of stainless. Stainless has only 3% the conductivity of copper. This alone will stop the 102" stainless from being the top performer. Subtract also the fact that the 102" stainless bends over in the wind and is also a relatively thin antenna. So what is the best choice? It appears that for a realistic antenna, it is a mildly loaded top or center loaded antenna made of thick conductive materials. There are a few of these ugly looking antennas around. They do work marginally better than the 102" stainless and have the benefit of being shorter. These antennas can get as short as five foot and still equal or outperform the 102" stainless. Percent conductivity of materials, based on copper being the standard of 100% Aluminum 65% Brass 28% Chrome 74% Gold 71% Iron 17% Silver 106% Steel 10% Stainless 3% ************************************** So.....Why has there not been a SS 102 with a heavy silver plate? K-40 was using silver plating in their load coils in the 70's and that hasn't changed as far as I know. Train |
#2
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On Sat, 25 Oct 2003 11:54:32 GMT, "Train" wrote:
************************************* All things being equal: 1.Top loaded antennas perform marginally better than base loaded 2.Taller antennas (less loading coil) perform better than shorter 3. Thicker antennas perform marginally better than thinner. 4. More conductive antenna stock makes a marginal difference over less conductive antenna stock. 5. A higher antenna mount works better than a lower mount. 6. A free and clear antenna mount works better than an obstructed one. 7. A more substantial RF ground works better than a minimal ground. This is true but I have seen installations that were actually OVERGROUNDED and hurt performance. How are why would that occur? 8. A vertical antenna performs better than a diagonal (windblown). Number 5, 6, & 8 are the most important factors in the performance of an antenna. Now if any one could come up with a formula that includes all of these factors then we would be able to answer your question. There is no formula. However we can say this. The best mobile antenna is a thick stiff nine foot whip that is silver coated and mounted on top of the roof with multiple radial grounding points. No one is going to use the antenna above in the real word, so one might draw the conclusion that in the real world we might substitute a 102" stainless whip for the best real world performance. WRONG. The 102" is made of stainless. Stainless has only 3% the conductivity of copper. This alone will stop the 102" stainless from being the top performer. Subtract also the fact that the 102" stainless bends over in the wind and is also a relatively thin antenna. So what is the best choice? It appears that for a realistic antenna, it is a mildly loaded top or center loaded antenna made of thick conductive materials. There are a few of these ugly looking antennas around. They do work marginally better than the 102" stainless and have the benefit of being shorter. These antennas can get as short as five foot and still equal or outperform the 102" stainless. Percent conductivity of materials, based on copper being the standard of 100% Aluminum 65% Brass 28% Chrome 74% Gold 71% Iron 17% Silver 106% Steel 10% Stainless 3% ************************************** So.....Why has there not been a SS 102 with a heavy silver plate? K-40 was using silver plating in their load coils in the 70's and that hasn't changed as far as I know. Train Just cover the S/S whip with copper braid. Copper is almost as good as silver. |
#3
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How can you shorten a fiberglass whip from the bottom??? I am interested in
trying it |
#4
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snip
So.....Why has there not been a SS 102 with a heavy silver plate? K-40 was using silver plating in their load coils in the 70's and that hasn't changed as far as I know. Train Just cover the S/S whip with copper braid. Copper is almost as good as silver. Yes, and when you do this nothing shorter will beat it. |
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