>I don't understand how you matched the dipole via 1,5 nF.
>Can you explain that to me?
Including the 42m open wire feeder it is effectively too long,
see also attached screenshot (from summer with dry weather)
The recorded measurement is showing
R=49,3 Ohm X= +j 169,8 Ohm
So you would need ~ 2nF for a perfect match.
The impedance varies of course with air and soil humidity etc.,
presently I need 1,5nF.
73
Clemens
DL4RAJ
>-----Original Message-----
>From: [email protected]
>[mailto:[email protected]] On Behalf Of C. Groeger
>Sent: Saturday, December 28, 2013 4:52 PM
>To: [email protected]
>Subject: RE: LF: mw activity
>
>Sorry Clemens,
>I don't understand how you matched the dipole via 1,5 nF.
>Can you explain that to me?
>73
>
>Christian Groeger
>
>Clemens Paul <[email protected]> schrieb:
>
>> >Will you use the dipole for xmitting?
>>
>>For sure,look at the matched feeding point impedance.
>>Matching is done with one single 1,5nF cap.
>>
>>73
>>Clemens
>>DL4RAJ
>>
>>
>>>-----Original Message-----
>>>From: [email protected]
>>>[mailto:[email protected]] On Behalf Of C. Groeger
>>>Sent: Saturday, December 28, 2013 11:19 AM
>>>To: [email protected]
>>>Subject: Re: LF: mw activity
>>>
>>>Clemens,
>>>Thanks for nice report!
>>>I'm very curious about your signal!
>>>Will you use the dipole for xmitting?
>>>Will be a big signal with that Ant!
>>>73, df5qg
>>>
>>>Christian Groeger
>>>
>>>Clemens Paul <[email protected]> schrieb:
>>>
>>>> DK7FC and DF5QG in CW both with 599 here until 00.05.
>>>>(DK7FC sometimes with 59~) :-)
>>>>QSB max. 6dB.
>>>>
>>>>http://no.nonsense.ee/qthmap/?qth=JN68KJ79WJ
>>>>
>>>>73
>>>>Clemens
>>>>DL4RAJ
>>>>
>>>>>-----Original Message-----
>>>>>From: [email protected]
>>>>>[mailto:[email protected]] On Behalf Of
>wolf_dl4yhf
>>>>>Sent: Friday, December 27, 2013 12:17 PM
>>>>>To: [email protected]
>>>>>Subject: Re: LF: Sending Opera with SpecLab
>>>>>
>>>>>Greetings all,
>>>>>(and apologies to Markus for juming in so quickly..)
>>>>>
>>>>>The principle described by Markus is only for transmission.
>>>>>To take place of the DS option, i.e. for RECEPTION, spectrum
>>>>>lab would have to modified to some extend, last not least it
>>>>>would need an 'automated' method to build the correlation
>>>>>patterns for the DS mode itself.
>>>>>Since Markus has already provided his opera generator (thanks
>>>>>for that!), it could be modified into a command-line driven
>>>>>tool (exe or dll) which SL could invoke to create the 239-bit
>>>>>message pattern for the correlators. I cannot promise too much
>>>>>yet (being busy from too many other projects) but maybe when
>>>>>the new 'super-linear', moderate-power, switching mode
>>>>>amplifier is finished I'll have a look at it again.
>>>>>
>>>>>All the best,
>>>>> Wolf DL4YHF .
>>>>>
>>>>>Am 27.12.2013 02:00, schrieb Bob Raide:
>>>>>
>>>>>
>>>>> Markus;
>>>>> Can this take the place of DS option used with OPERA?
>>>>>
>>>>>
>>>>>________________________________
>>>>>
>>>>> From: [email protected]
>>>>> To: [email protected];
>>>>>[email protected]
>>>>> Date: Fri, 27 Dec 2013 01:45:14 +0100
>>>>> Subject: LF: Sending Opera with SpecLab
>>>>>
>>>>>
>>>>> Today I finally found a simple solution to send Opera
>>>>>sequences from SpecLab's digimode terminal. The nice thing
>>>>>about this is that you can use all of SpecLab's powerful
>>>>>functions, like samplerate correction, adjustable pulse
>>>>>shaping, or high audio frequencies. This seems very useful,
>>>>>especially in the context of possible future VLF Opera
>transmissions.
>>>>>
>>>>> First you will need to create a text file consisting of
>>>>>the 239 bit 1101... sequence for your callsign. This can be
>>>>>generated from the PIC menu in the original Opera software. Or
>>>>>you can use my little code generator tool at
>>>>>http://df6nm.bplaced.net/opera/opera_generator.zip - simply
>>>>>copy opgen.exe from the zip and type
>>>>> opgen mycallsign >opera.txt
>>>>> into a command window.
>>>>>
>>>>> In SpecLab, open the digimode terminal and configure it
>>>>>for ASK with no encoding, as shown in the attached "_settings"
>>>>>screenshot. The symbol rate has to be set to the inverse
>>>>>dotlength for the desired Opera speed:
>>>>>
>>>>> mode dotlength rate
>>>>> (seconds) (sym/s)
>>>>>
>>>>> Op-8 1.024s 0.9766
>>>>> Op-32 8.192s 0.12207
>>>>>
>>>>> Op-4H 65.536s 0.01526
>>>>>
>>>>> Shaping time can be selected from hard (0%) to soft
>>>>>(50%) keying. Then enter your desired audio frequency and use
>>>>>"Load TX text" from the file menue to load your opera.txt
>>>>>file. The sequence will appear in the TX window, and the
>>>>>transmission can started by hitting the RX / TX button.
>>>>>
>>>>> Best 73,
>>>>> Markus (DF6NM)
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>
>
MW Dipole unmatched.gif
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