Return to KLUBNL.PL main page

[Top] [All Lists]

Re: LF: Re: Antenna change over relay question

To: [email protected]
Subject: Re: LF: Re: Antenna change over relay question
From: Andy Talbot <[email protected]>
Date: Mon, 24 Jul 2017 16:40:08 +0100
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to; bh=yr1WmbgWiWX+3OFRluKp1O5SinqCIrdaz+jmcgBL0nk=; b=fFWpxnMm1z80ODxphhbiRg1hcxyK1jidfW2s0uZG3ea/14Mww81zLjBhHqa+uBOVXx NHYDJbhOLP0EpKzvBbpN8AkdI10fCyqB9YisU4aewXpvXgW/afZHPd8+BIm3MOnTbCNP X9zGHh+0IhretB8sua9UNRaTWHj2dD/JaHbWCu/0nVgsIs5Ip6poQUZz88RoykgfqG6W +y3jG0DIqdzjF375/e/nlwat4/i0sw89sV2lUSpgVYYYatODuc2K7AXnKpeokvDhxI+I jzwUGkv6azZq8goINL78A/rJGyJ8Zy+aPRymcQGj7ds6xo1Bs2YTJkGcQ2ctUnT6EvjS UEiw==
In-reply-to: <[email protected]>
References: <[email protected]> <[email protected]> <[email protected]> <[email protected]>
Reply-to: [email protected]
Sender: [email protected]
Digressing slightly, but a parallel warning...

I once hot disconnected  a BNC plug carrying 700 Watts of RF (Low Z, transmitter output) .    As the contact broke it generated  a plasma arc that shot out of the BNC plug that I dropped in shock.  It continued to burn, vaporising the centre pin of the BNC, and burning a mark into the floor surface I'd dropped it onto.


On 24 July 2017 at 15:58, Chris Wilson <[email protected]> wrote:
Hello Ian,

You  have me worried now, as does Andy with his last post, the thought
of  putting  a kilowatt into the RX antenna socket of my 590 is not a
pleasant or cheap one... Hmmm.

Monday, July 24, 2017, 3:40:38 PM, you wrote:

> Hi Chris/Stefan

> Loosely connected to your question, I wanted to switch my Inv L between
> LF/MF Variometer/loading coils and HF Auto remote tuner remotely, i.e 120'
> away from the shack.

> Every relay I tried had insulation break down and contact arc over. Only
> running 360 W at MF and 300 at LF.

> My solution was to fabricate a 3 position Knife type switch operated via a
> Servo motor to switch the antennae and a standard 20 Amp Rated relay for the
> RF inputs to the Tuner and Variometers.

> No more insulation break down or arc over. The contacts are mounted on Old
> Eddystone porcelain insulators.

> I would be interested to know how the relay holds up with 1 kW at 136 kHz.

> 73

> Ian G4GIR

Best regards,
 Chris                            mailto:[email protected]

<Prev in Thread] Current Thread [Next in Thread>