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Re: LF: MFJ 259B HF antenna analyzer modification

To: [email protected]
Subject: Re: LF: MFJ 259B HF antenna analyzer modification
From: Steinar Aanesland <[email protected]>
Date: Sat, 21 Jul 2012 08:55:42 +0200
In-reply-to: <[email protected]>
References: <[email protected]> <[email protected]>
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Hi Stefan. Thanks for your answer :)

la5vna S


Den 20.07.2012 15:12, skrev Stefan Schäfer:
> Hello Steinar,
>
> Am 20.07.2012 11:43, schrieb Steinar Aanesland:
>> Hi Stefan
>>
>> Is this the MFJ 259B HF antenna analyzer modification?
>>
>> http://www.we0h.us/Amateur_Radio_stuff/MFJ/MFJ-259B/LF-MF-Mods/
>>
>> la5vna S
>>    
>
> Yes, this it is! Well documented by a few images. For LF i used a 10mH
> fixed inductor (looking about like a resistor) and for MF i took a
> FT50-77 and about 30 turns or so. A fixed inductor would work as well
> i think. Just insert it and see what the range is...
>
> 73, Stefan/DK7FC
>
>
>
>>
>> Fra: [email protected]
>> [mailto:[email protected]] På vegne av Stefan Schäfer
>> Sendt: 19. juli 2012 01:55
>> Til: [email protected]
>> Emne: Re: LF: 630 meter full size dipole
>>
>> Hi Jay,
>>
>> Interesting, thanks for the info!! Yes and that could be a real
>> alternative for those with a small garden and a stressing XYL. The wire
>> for the dipole can be quite small and fits into a backpack.
>> Then its a question of the dependency of the antenna efficiency as a
>> function of the ground conductivity. This will be one of the interesting
>> results!
>> 10m above ground is not much for a 630m band dipole but if the
>> difference to 2m above the ground is just a few dB, one can easily
>> through out the wire during taking a walk and can do some MF /p
>> operation, without a kite, without the need for a free field, without a
>> tower, without a good earth (connection)... Many advantages! Maybe...
>>
>> BTW i have also modified (extended) the range of my MFJ 259B HF antenna
>> analyzer to cover MF (313...658 kHz) and LF (103...209 kHz). This
>> modification is done very easy! I'm not sure how accurate the
>> measurements are in that range but maybe it gives me some ideas "where i
>> am".
>>
>> Looking forward to that test!
>>
>> 73, Stefan/DK7FC
>> Stefan
>>
>> This may be of interest for your next exploit ...
>>
>> Looking back in my 500 kHz log, I see that on 1/3/2010 I had a CW QSO
>> with WD2XSH/35 in South Dakota ... who was running a full size 600 meter
>> dipole. As I recall his antenna was relatively low at 30 or 40' above
>> ground and he was running only 50 or 100 watts. His signal was weak but
>> solid copy over the few nights that he was active. Distance was 1210 mi
>> / 1950kM. Believe his antenna was 'out in the open' as he apparently
>> owns a good sized farm.
>>
>> Jay W1VD  WD2XNS  WE2XGR/2
>>
>>
>>
>>
>>    
>
>




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