[Boatanchors] Coax Switches and Wire Antennas

[Carl]

A sheet of plexiglass, as many large diameter brass screws as there are 
antennas plus one, a piece of spring brass, a couple of brass shaft bushings 
and a fiber glass shaft can form the basis of a switch capable of handling 
any voltage or current you are likely to find.

Carl
KM1H


----- Original Message ----- 
From: "Bill Stewart" <cwopr at embarqmail.com>
To: <boatanchors at mailman.qth.net>
Sent: Wednesday, March 30, 2011 7:22 PM
Subject: Re: [Boatanchors] Coax Switches and Wire Antennas


> Tnx Gary, another good idea...Bill
>
> ----- Original Message -----
> From: "Gary Schafer" <garyschafer at comcast.net>
> To: "D C *Mac* Macdonald" <k2gkk at hotmail.com>, w7qho at aol.com, "K4JYS 
> Stewart, Bill" <cwopr at embarqmail.com>
> Cc: boatanchors at mailman.qth.net
> Sent: Wednesday, March 30, 2011 7:12:49 PM
> Subject: RE: [Boatanchors] Coax Switches and Wire Antennas
>
> A sheet of plexiglass with banana jacks.
>
> 73
> Gary  K4FMX
>
>
>> -----Original Message-----
>> From: boatanchors-bounces at mailman.qth.net [mailto:boatanchors-
>> bounces at mailman.qth.net] On Behalf Of D C *Mac* Macdonald
>> Sent: Wednesday, March 30, 2011 4:47 PM
>> To: w7qho at aol.com; K4JYS Stewart, Bill
>> Cc: boatanchors at mailman.qth.net
>> Subject: Re: [Boatanchors] Coax Switches and Wire Antennas
>>
>>
>> If you are worried about a flashover why not try
>> to find a LARGE manual switch at a flea market or
>> hamfest suitable for the bandswitch in a pi-network
>> high power amplifier?  Mount it using an aluminum
>> bracket on a board and put a nice, big knob on it.
>> Could be lots cheaper than a commercial coax switch
>>
>> No worries then!
>>
>> * * * * * * * * * * *
>> * 73 - Mac, K2GKK/5 *
>> * (Since 30 Nov 53) *
>> * Oklahoma City, OK *
>> * USAF, Ret (61-81) *
>> * * * * * * * * * * *
>>
>>
>>
>>
>> > From: w7qho at aol.com
>> > To: cwopr at embarqmail.com
>> > Date: Wed, 30 Mar 2011 13:40:24 -0700
>> > CC: boatanchors at mailman.qth.net
>> > Subject: Re: [Boatanchors] Coax Switches and Wire Antennas
>> >
>> > Bill,
>> >
>> > If you plan to use the classic Windom (half wave top section, single
>> > wire feeder) the impedance looking into the feedwire "should" be
>> > something around 600 ohms. Cut and try required to find the correct
>> > tap point on the flat-top and the length of the feed wire and the
>> > ground system used also have an effect. Probably OK through your coax
>> > switch at the 75 watt level but only for the frequency/band for which
>> > the flat top was cut. On harmonic related frequencies (ex. 40M
>> > operation on a flat top cut for 75M) the impedance looking into the
>> > feedline could be just about anything.
>> >
>> > For the end-fed case, how long is the wire and what frequency/
>> > frequencies are you using? OK for your switch if the feed point is
>> > anywhere near a current loop.
>> >
>> > Dennis D. W7QHO
>> > Glendale, CA
>> >
>> > *****
>> >
>> > On Mar 30, 2011, at 7:07 AM, Bill Stewart wrote:
>> >
>> > >
>> > >
>> > > Good morning all,
>> > >
>> > > Can a normal coax switch be used to switch single wire fed antennas
>> > > such as a long wire or OCF Hertz (windom-a hi imped. antenna), in my
>> > > case. No coax feed used, just a wire from the wire antenna thru the
>> > > center conductor of the switch and then to the xmtr or tuner. I have
>> > > 'heard' that a coax connector presents a 50 ohm 'lump' in the line.
>> > >
>> > >
>> > >
>> > > I know this can be done electrically, but just wondering about the
>> > > '50 ohm' situation. Tnx for helping with a stooopid question.
>> > >
>> > >
>> > >
>> > > 73, Bill K4JYS
>> > > ______________________________________________________________
>> > > Boatanchors mailing list
>> > > Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>> > > Help: http://mailman.qth.net/mmfaq.htm
>> > > Post: mailto:Boatanchors at mailman.qth.net
>> > >
>> > > List Administrator: Duane Fischer, W8DBF
>> > > ** For Assistance: dfischer at usol.com **
>> > >
>> > >
>> > > This list hosted by: http://www.qsl.net
>> > > Please help support this email list: http://www.qsl.net/donate.html
>> >
>> > ______________________________________________________________
>> > Boatanchors mailing list
>> > Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>> > Help: http://mailman.qth.net/mmfaq.htm
>> > Post: mailto:Boatanchors at mailman.qth.net
>> >
>> > List Administrator: Duane Fischer, W8DBF
>> > ** For Assistance: dfischer at usol.com **
>> >
>> >
>> > This list hosted by: http://www.qsl.net
>> > Please help support this email list: http://www.qsl.net/donate.html
>>
>> ______________________________________________________________
>> Boatanchors mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Boatanchors at mailman.qth.net
>>
>> List Administrator: Duane Fischer, W8DBF
>> ** For Assistance: dfischer at usol.com **
>>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
> ______________________________________________________________
> Boatanchors mailing list
> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Boatanchors at mailman.qth.net
>
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html