Hi Chris,
I also think that a carrier interruption may be more suitable than DFCW,
because it's easy to retain the carrier phase phase, such that a narrow FFT
can integrate across the gaps. For this to work, it is necessary to let
oscillator and dividers (!) run through, and apply the keying only to the
amplifier.
Best 73,
Markus (DF6NM)
From: mal hamilton
Sent: Thursday, February 10, 2011 7:00 PM
To: [email protected]
Subject: Re: LF: VLF Transmissions - G3XIZ - 12th / 13th February
Chris
Some sort of ID is necessary. I arranged with OE5ODL to cut carrier for pos
id. A continuous carrier needs regular cuts.
QRS is preferable to DFCW as an ID tool.
also
regular feedback reporting is also necessary.
g3kev
----- Original Message -----
From: Roger Lapthorn
To: [email protected]
Sent: Thursday, February 10, 2011 5:52 PM
Subject: Re: LF: VLF Transmissions - G3XIZ - 12th / 13th February
Hi Chris,
Very good luck. I'll be looking for you and hoping for success this time.
An email direct and to this group saying when TX starts/ends would be
helpful. Don't suppose you can send QRSS60 or similar to help with ID? Have
passed the word on to Nick G4IKZ as he is closer to you than me and not sure
he subscribes to this list.
73s
Roger G3XBM
On 10 February 2011 14:42, Chris Osborn <[email protected]> wrote:
LF,
I have had permission to transmit on VLF this coming weekend: 12th and 13th
February.
Weather permitting I shall try again with my balloon-launched aerial,
hopefully about 50m vertical.
The frequency will be
8.976 66 kHz (i.e. 10.000 MHz / 1114) and is derived from an oven
controlled xtal oscillator.
Hopefully the frequency will be more stable than last time.
If this frequency proves unsuitable I can transmit on 10.000 MHZ / 1112 .
.10.000 MHz / 1116 etc.
I shall send a continuous carrier as and when conditions permit.
My newly built VLF TX is working well and can deliver about 150 watts of RF.
On this occasion I shall be using the original (fairly lossy) loading coil
but am presently making a more efficient one.
All reports will be most welcome.
73
Chris G3XIZ
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