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Loggings => Longwave Loggings => Topic started by: Uli_Bel on February 06, 2018, 0943 UTC

Title: NDB "LT" on 305kHz very loud last night in Belgium
Post by: Uli_Bel on February 06, 2018, 0943 UTC
Hi,
just newly registered from Belgium...

Here is my first NDB-log:
305kHz - LT, Alert Bay from very northern Canada...
oud here in Belgium
Almost all night 15db over noiselevel with peak of 20db S/N ratio at peaks.
 
Title: Re: NDB "LT" on 305kHz very loud last night in Belgium
Post by: Uli_Bel on February 06, 2018, 1243 UTC
Also heard here in Belgium at just after 4h utc this morning:
329khz "YEK"  - Arviat NDB, Nunavut, Canada

Signal strength was just enough to clearly identify the station, as there was some weak QRM from Jersey NDB and Norway, even I used 100Hz CW-filter
According to Arviat Airport website, they use 500wtts power - radiated power is probably only about 10wtts, due to the high losses at such low frequency.

Amazing, what can be done, if propagation is well
I found that at our local sunrise propagation picked up at least 10db for only 10min or less... didn't know that sunrise peak is so pronounced at such low frequency...
My lowest frequency of activity was 1.8Mhz amateur radio in the past...

Ulli, ON5KQ
web-radio link:
http://on5kq.ddns.net:8073 (http://on5kq.ddns.net:8073)

Title: Re: NDB "LT" on 305kHz very loud last night in Belgium
Post by: pinto vortando on February 06, 2018, 2301 UTC
Nice one... 329 YEK,  that's almost 3500 miles from there to ON land !
The "Eskimo Point" beacon shows up here in Michigan once in a while and when it does it has a good signal...  all or nothing.
Title: no copy of YEK last night in Belgium...
Post by: Uli_Bel on February 07, 2018, 1046 UTC
Conditions last night (6-7Febr) were very different...
Much weaker signals from LT and no copy of YEK this time.
I published my results of DGPS reception in the DGPS folder, for propagation judgements...

Lots of NDB beacons though - I have not reviewed my recordings yet ...

Ulli
Title: Re: NDB "LT" on 305kHz very loud last night in Belgium
Post by: jFarley on February 07, 2018, 1631 UTC
Ulli;

Welcome to these pages, and congratulations on logging LT 305.  That is a great catch!

I have not had the good fortune to log LT here in Chicago.  To the best of my knowledge and if memory serves me, LT has been logged in the USA only once.  That was about 10 years ago, and it was logged by another listener in my town, so I know it is possible.  Last season I was able to detect the DAID and possibly a smeary "L", but that's it.  With the approach of the solar minimum, we are hoping that LT makes it here some time in the future!

Looking forward to your contributions!
Title: Re: NDB "LT" on 305kHz very loud last night in Belgium
Post by: Uli_Bel on February 11, 2018, 2137 UTC
Again - today, sunday evening in Belgium, testing my new broadband vertical antenna... good condition:
NDB from most northern point of Canada:
LT, from Alert Bay, CAN (Nu) very loud here at 21h30 utc (11Febr2018) - already comfortable 15db S/N ratio

Band is packed with weak NDB's - very unusual at this time ...

So check the band after sunset in North-America...

Regards,
Ulli, ON5KQ
http://on5kq.ddns.net:8073 (http://on5kq.ddns.net:8073)
Web-receiver in my garden...
Title: Re: NDB "LT" on 305kHz very loud last night in Belgium
Post by: pinto vortando on February 11, 2018, 2359 UTC
Ulli,

What type of "broadband vertical antenna" do you have?
Title: Re: NDB "LT" on 305kHz very loud last night in Belgium
Post by: Uli_Bel on February 14, 2018, 1233 UTC
About my broadband vertical:

The radiator is a 10m high vertical 60mm aluminium pipe, completly insulated from ground.
The counterpoise are about 10pcs of 10m long wires, horizontal 1-2m above the ground (elevated radials)

I connected a high impedance input pre-amp directly between elevated radial network and the vertical. The input of the pre-amp is carefully balanced with a very high mu torroid, to prevent IM2 products in the electronics.
The output of the pre-amp drives CAT5 cable heavily choked and bypassed to prevent common-mode interference in the high imp. pre-amp..

The system is very sensitive against common-mode problems due to the pre-amp which is sensitive for common-mode (unwanted noise) and differential-mode signals (antenna output).

Output of the pre-amp is that high, that you need 15db of attenuator in front of a todays sdr receiver (for example ELAD FDM-S2)
Mediumwave band ist full of -10dbm signals, although no local transmitters.... nearest transmitter ist about 100km and not very high power.

Due to the pre-amp, the antenna is very broadband, as the high impedance of the pre-amp does not load the induced voltage a lot but can drive my feed-cable with good match (Belden Cat5E has about 110Ohm impedance which is matched to 50Ohm in front of the receiver.)

For NDB bands and also DGPS reception, I use my QS1R SDR-receiver. This receiver does not use a active front-end, so it is very well suited for extremely strong signals (overload at about +9dbm).

Ulli, ON5KQ