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Re: LF: Re: 137khz RX-Test

To: [email protected]
Subject: Re: LF: Re: 137khz RX-Test
From: Gerhard Hickl <[email protected]>
Date: Sun, 21 Jun 2009 21:24:58 +0200
Disposition-notification-to: [email protected]
In-reply-to: <[email protected]>
References: <1245582735.4291.6.camel@gerhard-laptop> <33D6A4990B7B45149663D84D52C052CA@JimPC> <1245595125.3782.14.camel@gerhard-laptop> <[email protected]>
Reply-to: [email protected]
Sender: [email protected]
Hello Group!

@James: Thanks a lot. Built a L-filter and the sensitivity is now at
least 10db (maybe even more) better. -60dbm (instead of -50dbm) fed into
the same wire than before can now be seen clearly. I just had some
assembled ferrite rods for MW with coils less than 1mH and they didn't
work. Then I applied about 200 turns to a ferrite-rod and got a coil of
5,1 mH. With this coil and a 10-320pf capacitor, I was able to match the
impedance of the wire to the input of my RX. Thank you again for the
hint. The entire assembly is "bread-board style" for now with a lot of
"flying wires" and without any shielding.

@Heinz: Thanks a lot too. I have seen on the Internet, that OE5ODL is a
very active station on LF. I will get back to you for the schedule on
your personal address. 


For now, I'm waiting for James beacon which will hopefully appear on my
screen at 2000z.

Cheers and 73 de
OE3GHB

Gerhard Hickl




 



Am Sonntag, den 21.06.2009, 20:41 +0200 schrieb H Schnait:
> Hello Gerhard,
> 
> OE5ODL can put out a respectable signal whenever you want. I can help 
> set up a sked, if you reply to my email adress (just google my callsign).
> 
> 73 Heinz, OE5EEP
> 
> 
> Gerhard Hickl schrieb:
> > Hello James and the group!
> >
> > Thanks for the reply. Unfortunately I can't copy your signal in the
> > moment, let's hope for the evening/night.
> >
> > I'm using my shortwave-antenna, a 55m long endfed wire in about 12m
> > height as antenna for lf. it's connected to the unsymmetrical input of
> > the Selective Level Meter. I think using this antenna is the first
> > problem. Another one ist that I don't have a preamp yet. The 2nd antenna
> > is a resonant frame antenna with about 1m diameter. Unfortunately I
> > haven't managed to bring it outside somehow and so I'm using it in the
> > shack which gives me a lot of QRM, especially from the tube-monitor
> > (n*75Hz vert. frequenzy).
> >
> > The Level Meter only has a 22Hz and a 3.1khz filter. I just can use the
> > 3.1 filter which gaves me lot of QRM from DCF39. I have tuned to 137.15
> > becasue I found that this qrg is quiet (-107dbm) compared to some 100Hz
> > up and down where the noise level is up to -92dbm. I think this noise is
> > produced by the carrier of DCF39 somehow.
> >
> > As you may have noticed, I'm a LF beginner and it seems I have to work
> > on the sensitivity of my equipment. I'm living 30km north of Vienna and
> > I think QRN and QRM is not so bad here.
> >
> > Any suggestions welcome.
> >
> > Thanks a lot
> > and 73 de OE3GHB
> >
> > Gerhard Hickl
> >
> >   
> 
> 
> 



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