Message-ID: <5AA9673D.4090509@posteo.de>
Date: Wed, 14 Mar 2018 19:17:33 +0100
From: DK7FC <selberdenken@posteo.de>
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3
MIME-Version: 1.0
To: rsgb_lf_group@blacksheep.org
References: <1621f5d38b9.marcocadeddu@tin.it> <579355A36AEE9D4FA555C45D556003ABA3C2F32B@servigilant.vigilant.local>
In-Reply-To: <579355A36AEE9D4FA555C45D556003ABA3C2F32B@servigilant.vigilant.local>
Subject: Re: LF: LU1DOW soon in MF/LF
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org

Hi Luis,

Thanks for the feedback. I think with EbNaut it will be possible to 
reach the European LF sites for a decode! A big challenge. And MF could 
be even easier, at least for RX sites like EB8ARZ and so on, those close 
to the sea... Ah yes, think about FR5DH!

Good luck to Oscar. We are waiting for him!

73, Stefan

Am 14.03.2018 19:01, schrieb VIGILANT Luis Fernández:
> Hi All, LF
>
> More comments in behalf of Oscar, LU1DOW and his thanks for the interest in his work
>
> Rik: Oscar included class B in the PA just for testing some linear modes if there is any future need. It is true that DFCW do not need linear PA
>
> Marco: It is not a modified PA. The output was designed as a simple PL circuit, so to resonate it in LF with the coil shown in the pictures it was necessary to add
> a high capacity in parallel with the plate tunning capacitor. High voltage mica capacitors are used there
>
> Stefan: Oscar will be happy to make tests in EbNaut as soon as possible and he is very grateful for your help and good advices
>
> 73 de Luis
> EA5DOM
>
> -----Mensaje original-----
> De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de marcocadeddu@tin.it
> Enviado el: martes, 13 de marzo de 2018 13:37
> Para: rsgb_lf_group@blacksheep.org
> Asunto: R: RE: LF: LU1DOW soon in MF/LF
>
>
> Hi Luis, Chris and LF,
>
> enjoyed the pictures from Oscar.. when I see tubes my heart..
> I don't wonder for the filament current (at 5V it means 150W) but how Oscar arranged the PI or PL output matching circuit: I guess he modified an HF PA and it means a lot of L and C to retune from 160m..
>
> Hope to hear soon Oscar on LF/MF.
>
> Now I'm testing the new TX for MF it is on since last saturday 24h/24h trasmitting WSPR2 every 10 minutes.
> I need some fine (at least dry..) weather to tune and match better the antenna because now the return loss is not really wonderful (almost 10
> dB..) so I haven't any idea of the ERP but it should be in the range of 200mW.
>
> Enjoy MF/LF and lower ;-)
>
> 73, Marco IK1HSS
> ----Messaggio originale----
> Da: luis@vigilant.es
> Data: 13-mar-2018 11.28
> A: "rsgb_lf_group@blacksheep.org"<rsgb_lf_group@blacksheep.org>
> Ogg: RE: LF: LU1DOW soon in MF/LF
>
> Hi Chris, LF
>
> Oscar answered the question. I'll try to translate, but can't promise not to make a mistake in tube terminology :-)
>
> He is not using filament choke as this is a direct heating tethrode. So the midpoint of the filament transformer secondary is connected to ground The driving is to the grid with a tuned circuit. It works in C class for QRSS and B Class for DFCW. And YES, this a dangerous high voltage bricolage and a waste of energy. Just the filament is sucking 35.5 Amps :-O
>
> Oscar plans to test first single carrier in LF with LU8YD at 1000Km first to check if all is going as in previous tests some time ago.
> After that he will switch
> to MF and test again
>
> 73 de Luis
> EA5DOM
>
>
>
>
>
>
>
>