Hello, Rik ang LF Group.
On Mon, 25 Mar 2002, Rik Strobbe wrote:
You are in the range of 4000 to 4700 km of most European LF stations. That
might be a bit too much for normal CW. But trans-atlantic tests in the past
years have shown that with a few 100mW ERP it is possible to copy QRSS
signals over a range of 5000 to 6500km. And you have the advantage that you
have a rather northern location, so even this time of the year there a a
good 'dark path'.
I have never think about QSO with Europe because I thought that even in
QRSS mode ERP more then 1 W should be. Your words have change my opinion.
It seems posible for me to radiate 50 or 100 mW.
Regarding the VFO : a drift of no more than few Hz/hour is required for 3
to 10 sec. dotlength, a VXO or PLL is prefered but a good VFO might do it.
My VFO is not very good because it was builded for normal CW operation.
OK. I will be lookin for XTAL for this frequency. There is some oportunity
to get such a XTAL.
I prefer to use PIC16F84 microcontroller as QRSS TX keyer, not PC. To
build such a keyer I should know:
1. What dot duration accurancy should be?
2. What is standard dotlenth and should it be very stable? May be I can
use RC generator in the controller...
3. Should I do any synchronization of each dot/dash start to global time?
If not it's better...
73 de RA9MB/Alex
http://www.qsl.net/ra9mb
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