Hi Mal,
1 KW should be enough for a regular CW QSO I suppose.
But on the other hand: my antenna efficiency is very low. I did some
calculations with MMANA-GAL and the radiation resistance of my 30 mtr long
end-fed antenna is only 0.019 Ohm…
And there is no simple way to improve (lengthen or make it higher).
Measurement with my AIM4170 Antenna Analyzer shows a total antenna system
impedance of 150 Ohms at 136 KHz. So the efficiency is only 0.019/150 =
127x10^-6.
This means that with 1 KW output the ERP is only 0.13 Watt. I hope it is
enough..
Kind regards,
Minto pa3bca
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Ceterum censeo Carthaginem delendam esse
-----Original Message-----
From: mal hamilton
Sent: Saturday, July 23, 2011 10:28
To: [email protected]
Subject: LF: Re: Re: DL6NN on 137
Hi Minto
Let me know when you are QRV for a QSO on 137. CW will be satisfactory for
both ends with our power and mine
73 es gl
de mal/g3kev
----- Original Message -----
From: "Minto Witteveen" <[email protected]>
To: <[email protected]>
Sent: Friday, July 22, 2011 10:00 PM
Subject: LF: Re: DL6NN on 137
Well, I am all for it..
Now that we (PA) are kicked off of 500 KHz (again!) I needed another
challenge. So 136 KHz it is.
I have already built a PA for 136. My design is for > 1KW, I have only
tested it at 650 Watt as my current power supply cannot handle more, and
the
same goes for my dummy load.
But I do have a 50 Volt 1.2 KW supply that should do the trick.
I do not think QRP is an option on 137 KHz - especially with my antenna
(Mal
wil probably concur :-) )
Next step is building a variometer (3.5 to 4 mH), and the mixer/driver so
I
can use my ft817 like in the 500 KHz setup.
Don’t expect met to appear on 136 any time real soon however,
unformtunately
I do not have much time at the moment to complete the project. My target
is
the end of August.
For those interested: I have created a quick and dirty webpage with some
info abt my experiment:
http://www.pa3bca.nl/index.php?option=com_content&view=article&id=22&Itemid=
16
Regards,
Minto pa3bca
-----Original Message-----
>From: Stefan Schäfer
>Sent: Friday, July 22, 2011 20:07
>To: [email protected]
>Subject: Re: LF: Re: DL6NN on 137
>He seems to be new on the band. No other stations visible in the moment.
>Surely it would be a positive impulse if new stations could get some
>QSOs. This could start a positive spiral of activity. It's up to us...
>DL6NN in JO30VC, OM Lutz. 99km distant to me, 250km to DF6NM.
>73, Stefan/DK7FC, still in QSO
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