static high voltages of antenna protect

[tzitzikas]

i have an inverted L antenna for medium waves. i would like to ground the static high voltages. the antenna has static high voltages when the weather is not good.
i am looking for a easy system to ground this voltages and to protect my transmitter and the tuning circuit.
i had seen a schematic with carbon resistance about 10kohm which is connected between the antenna and ground. this solution is ok? do you have to propose any idea?

 

[bamacj]

Try here they might have something to help.



Industrial Communication Engineers, LTD.

 

[sp5it]

Put 100k resistor between antenna wire and ground. That's all.
MIke

 

[Captain Kilowatt]

The 100K resistor will work but will also react slow if the charge rate is quite high as it can be in the wind. We used a choke directly from the antenna to ground on all the AM broadcast towers. The choke coil was about 2-3 inches in diameter and about 10 inches long and wound with small gauge wire approximately 20 gauge. The coil presented a high impedance to the AM broadcast frequency but a dead short to any static charge. Wire size does not really matter because it does not have to handle any of the transmitter's RF,just the DC static charge.

 

[tzitzikas]

The 100K resistor will work but will also react slow if the charge rate is quite high as it can be in the wind. We used a choke directly from the antenna to ground on all the AM broadcast towers. The choke coil was about 2-3 inches in diameter and about 10 inches long and wound with small gauge wire approximately 20 gauge. The coil presented a high impedance to the AM broadcast frequency but a dead short to any static charge. Wire size does not really matter because it does not have to handle any of the transmitter's RF,just the DC static charge.

how many turns required my friend?

 

[Captain Kilowatt]

Basically take a piece of PVC or plastic pipe about 2 or 3 inches in diameter and wind it with as much insulated wire of about 20-24 gauge,as you can fit into a single layer and make it about 18 inches long. My previous statement of about 10 inches was wrong :headbang. Sorry about that. :blush: The best wire to use is enamalled wire as you can get more turns due to the smaller diameter. The exact number of turns is not an issue as long as there are enough to present a high impedance at the operating frequency. The idea is not affect the RF but present a dead short to the DC static.