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Date: Thu, 02 Jun 2011 22:02:39 +0200
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References: <E1QS2lL-0006rg-00.rn3aus-mail-ru@f294.mail.ru> <4DE77961.4040800@iup.uni-heidelberg.de> <E1QSAJs-0002rn-00.rn3aus-mail-ru@f238.mail.ru>
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Subject: Re: LF: Re[2]: LF: LF: OE5ODL 31 May  and my tx-beacon
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Hello Alex,

You can easily build an LF amperemeter by rectifying the LF current.=20
Take a normal analog amperemeter (FS=3D 100 uA or 1 mA) and build a bridge=
=20
rectifier (4 diodes) out of fast switching diodes (e.g. UF5400 =20
(http://www.datasheetcatalog.org/datasheet/vishay/uf5400.pdf ) ). Then=20
you must add a parallel resistor, parallel to the amperemeter. You can=20
use e.g. a 100 Ohm potentiometer and have to calibrate it. Add a small C=
=20
like 100 nF parallel to the meter. You can calibrate it by using a=20
temporary 1 Ohm resistor and measure the voltage across it with an=20
oscilloscope. Or you can use a 50 Hz current for calibration too and=20
measure with a standard amperemeter in series...

73, Stefan/DK7FC

Am 02.06.2011 18:00, schrieb Alex K:
> Thank you Stefan!
> Yes, QRN in my QTH also vy strong.
> Unfortunately I don't have antenna curent meter. :(
> In the winter of 2010-2011 I had also QSO with RN3AGC, RA3YO and EW6GB=
 in DFCW-10. Probably my ERP is less, than I think.
> There can be a problem that my loading coil is reeled up by not so thick=
 wire and has resistance 26 Ohm...
>
> 73 es TNX de Alex RN3AUS
>
> Thu, 02 Jun 2011 13:52:01 +0200 =D0=BF=D0=B8=D1=81=D1=8C=D0=BC=D0=BE =D0=
=BE=D1=82 Stefan Sch=C3=A4fer<schaefer@iup.uni-heidelberg.de>:
>
>   =20
>> Alex,
>>
>> Congrats for your first (?) LF detection at RN3AGC. The conds are very
>> poor in the last days in QRN in east EU is very strong. Sounds good
>> about your station and TX power. What antenna current do you achieve
>> with these 270 W? I'm sure to get a trace here soon too.
>>
>> 73 and go on :-)
>>
>> Stefan/DK7FC
>>
>> Am 02.06.2011 09:56, schrieb Alex K:
>>     =20
>>> Hello LF!
>>> 31 May rcvd weak signal OE5ODL with strong QRN in KO85sh.
>>>
>>> 01 June fm 18:00 z to 02 June 01:30 my TX beacon DFCW-120 running 270=
 W to
>>>       =20
>> ant invL 15 high 20 hor.
>>     =20
>>> My signal rcvd RN3AGC in KO86NP
>>>
>>> 73 de RN3AUS/Alex
>>>
>>>       =20