Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

Re: LF: VX9MRC QRV 507.77 kHz/ Arcing relays &c.

To: <[email protected]>
Subject: Re: LF: VX9MRC QRV 507.77 kHz/ Arcing relays &c.
From: "Graham" <[email protected]>
Date: Tue, 11 Oct 2011 12:17:27 +0100
Importance: Normal
In-reply-to: <[email protected]>
References: <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <1849736542-1318171189-cardhu_decombobulator_blackberry.rim.net-208700020-@b1.c11.bise7.blackberry> <FB0006513E634A96AFED8066F7C344C1@JimPC> <[email protected]> <BA4122BA92D44641A1BE5ED27FD763E5@JimPC> <[email protected]> <[email protected]> <[email protected]> <006c01cc87ab$427234c0$4001a8c0@lark> <[email protected]>
Reply-to: [email protected]
Sender: [email protected]

Joe..

There  are  some  'good'   rf relays  at  :-

http://www.surplussales.com/Relays/rfopen.html

Ive  used the  small  open  frame  one's  for  some time  on the  HF bands
may  be a couple of the  6 Kv   open  frame  in series  would  work ?

G..



--------------------------------------------------
From: <[email protected]>
Sent: Tuesday, October 11, 2011 2:11 AM
To: <[email protected]>
Subject: Re: LF: VX9MRC QRV 507.77 kHz/ Arcing relays &c.


Hi Alan, Group.

Thank-you for the reply. Multiple contacts in series were considered... but the gap has to
increase by orders magnitude!  How much gap will I need for 50 kV?

Your spiral pie story was most enlightening.  My pies are ~35 turns of
4mm litz about 37 cm diameter with L=0.24 mH. A stack of 4 yields
3mH.  Each pie has ~23 metres of litz.  Do you think this is will give
the most L for the least length of litz?

VX9MRC is still sending the 8 WPM beacon as yours truly looks at a fried
relay...

Cheers
Joe

On Tue, 11 Oct 2011, Alan Melia wrote:

Hi Joe, why not stick two sets of normal contacts in series....doubles the
gap :-))

Alan

----- Original Message -----
From: <[email protected]>
To: <[email protected]>
Sent: Monday, October 10, 2011 11:54 PM
Subject: Re: LF: VX9MRC QRV 507.77 kHz/ Arcing relays &c.


Hello Hartmut, Group.

Good to hear from you again, Hartmut.  Thank-you for  the report.

The beacon is on again, but there was some trouble: to use the tower
on 160m the 500 kHz tuning coil (0.2 mH) is shorted by a relay. The
N.O. contacts on this relay arced over.  Perhaps a high voltage (vacuum)
relay would help?

This  problem will be much worse on 137.777 kHz with the higher voltage.
I have some spiral wound 4mm (Decca) litz to make up the 3 mH for that
project.  (The spiral winding was inspired by G3NYK's experiments with
tuning coils on his web page.)

73
Joe

On Mon, 10 Oct 2011, Hartmut Wolff wrote:

Am 2011-10-09 23:50, wrote [email protected]:
Dear Group,
Reports on the 8 WPM CW beacon will be appreciated!
73
Joe VO1NA

Attached a screenshot of the 8wpm signal. The signal came up at about
23:20
and faded out at about 7:35. The strongest part was between 04:00-06:00
UTC
--
73
Hartmut
www.h-wolff.de
Locator: JO52hp


This electronic communication is governed by the terms and conditions at

http://www.mun.ca/cc/policies/electronic_communications_disclaimer_2011.php





This electronic communication is governed by the terms and conditions at
http://www.mun.ca/cc/policies/electronic_communications_disclaimer_2011.php






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