30 watts is correct for 1500 watts in a 50 ohm system and a coil Q of 226.
The power loss is 0.1 dB and the coil temp rise is around 20 deg C.
WX7G
On Jul 26, 2012 3:20 PM, "ZR" <zr@jeremy.mv.com> wrote:
> **
> That is only 226 Ohms at 1.8MHz and at 1500W will be dissipating about 30W
> in a 50 Ohm system but Phil didnt say how he is feeding his tower which is
> resonant well below 160M.
>
> Yes it will work as well as survive a lot of energy at 35-50 Ohms compared
> to a larger inductance 1A choke.
>
> Carl
> KM1H
>
> ----- Original Message -----
> *From:* DAVID CUTHBERT <telegrapher9@gmail.com>
> *To:* ZR <zr@jeremy.mv.com>
> *Cc:* philclements@centurylink.net ; topband@contesting.com
> *Sent:* Thursday, July 26, 2012 4:35 PM
> *Subject:* Re: Topband: Choke Construction Info Needed
>
> 20 uH should be sufficient at the base of a 1/4 wave length vertical.
>
> #4 copper wire is used to connect towers to ground for direct strikes.
>
> Such an inductor can be close-wound with insulated #4 wire, diameter 8", 8
> turns.
>
> It should survive intact except for the insulation.
>
> Dave WX7G
> On Jul 26, 2012 2:02 PM, "ZR" <zr@jeremy.mv.com> wrote:
>
>> It all depends upon how much survivability you want, nothing will survive
>> a
>> direct hit. Any 1.5 to 2.5 mH choke will suffice, just look at the safety
>> choke in a commercial amp for the smallest choice.
>>
>> The big ones are often found in scrapped BCB transmitters and tuning units
>> as well as show up at hamfests and on Fleabay as old military gear had
>> various candidates.
>>
>> Carl
>> KM1H
>>
>>
>> ----- Original Message -----
>> From: "Phil Clements" <philclements@centurylink.net>
>> To: <topband@contesting.com>
>> Sent: Thursday, July 26, 2012 3:03 PM
>> Subject: Topband: Choke Construction Info Needed
>>
>>
>> >I need to construct a heavy-duty choke to be installed from the feed
>> point
>> > of my 160 meter vertical to ground, for static drain and for lightning
>> > protection. How large does the wire, form, and inductance need to be?
>> >
>> >
>> >
>> > Thanks in advance for your expertize!
>> >
>> >
>> >
>> > (((73)))
>> >
>> > Phil, K5PC
>> >
>> >
>> >
>> > _______________________________________________
>> > UR RST IS ... ... ..9 QSB QSB - hw? BK
>> >
>> >
>> > -----
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>> >
>>
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>
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>
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>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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