Hi Stefan the effect at VLF and in daytime at LF may be different, the extra
electrons can slightly enhance daytime signals at LF but I have only detectd
that within a day or so of a CME impact. At VLF there may be an enhancement
as well I dont have any feel for that and comments on VLF beacons are
interesting.
Alan
----- Original Message -----
From: "Stefan Schäfer" <[email protected]>
To: <[email protected]>
Sent: Wednesday, September 14, 2011 12:44 PM
Subject: Re: LF: Re: low noise and OE5ODL
Hi Alan,
Thanks for the observations.
Am 13.09.2011 18:01, schrieb Alan Melia:
> Hi Stefan be careful with you appreciation of good conditions using the
> noise leevel!!
Have i been talking about good conditions?
> The noise usually drops because it is not being propagated so
> a low noise condition CAN be a state of poor propagation.
Yes, that should be the case now. And this applies for VLF too, at least
here in EU the band was very quiet, just like in winther. Also the time
window of low QRN is as low as in winther!
This may be a disadvantage for DX but on VLF, Ossi's signal has a nice
S/N for that antenna current and his non-Kite/ballon supportet antenna.
> I think that is
> the case at the moment. The CME associated with the X-Class flare pushed
the
> Dst down to -60nT and filled the Ring Current region with charge that will
> leak into the ionosphere over the following days. This increases the
> night-time absorption and reduces DX signal levels. A demo of this is to
> look at the levels recorded by Scott VE7TIL for a Russian BC station on
> 153kHz. This normally strong signal is depressed by 35 to 40dB at present.
>
Yes, also very good visible at http://icas.to/argo/dcf39.htm
Hope condx are back soon. When do you expect the conds are back to
normality?
Best 73, Stefan/DK7FC
> Alan G3NYK
> http://www.alan.melia.btinternet.co.uk/latest.htm
> "almost daily" propagation report for LF.
>
> ----- Original Message -----
> From: "Stefan Schäfer"<[email protected]>
> To:<[email protected]>
> Sent: Tuesday, September 13, 2011 4:03 PM
> Subject: LF: low noise and OE5ODL
>
>
>
>> LF/VLF,
>>
>> Very low noise today on LF and VLF.
>>
>> Ossi/OE5ODL is QRV again, today on 8970.05 Hz, with the characteristic
>> drift. A good ID :-)
>>
>> Just found some time to build a LF preamp for the ferrite antenna. Maybe
>> someone has fun and time to make some acty on 137.7 in a hour or so?
>> Would like to compare signal levels and S/N of both, the 50 Ohm preamp
>> and the high-Z preamp in a quiet location.
>>
>> Screenshots will be posted here...
>>
>> Best 73, Stefan/DK7FC
>>
>> PS: Will run a QRSS-3 beacon on 137.730 kHz, using 0 V PA supply voltage
>> (i.e. no supply). There is a weak signal anyway, just because the FETs
>> gets switched! This signal is visible at DF6NM in the QRSS-60 window in
>> 174 km distance! ;-)
>>
>>
>
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