RE: LF: Re: 134.1Khz

["Laurence KL1X" <hellozerohellozero@hotmail.com>]

roelof - that coupling was a 680nF not pf, my p's instead of n's - ! Well its going to get used again this weekend as Ive just been told to stay here till next Wednesday again (oh what a shame) - so Ill unpack the rx again and shove up the probe on the fishing pole from here in the 12th floor of the hotel. Im going to try it on VLF into the sound card and use SDR/Spec and see what I can hear. Wasnt so good last night lots of qrn and didnt hear/see the HBG time signal nor DCF39. That MSFSK signal on 54Khz (carrier) is pretty strong in the evenings so definitely East of here and maybe Canadian as Scott indicated. The signal on 133Khz is a local fluffy object with wings and not datatrack (thanks for the clips chaps). Ive got the hotel electrician to remove the 2 x 7W flourescent tubes from my patio whilst Im here.....they were flashing and causing noise, and the concierge has come up with another length of 30mm diameter white pipe "with end caps" -  quite some service from this hotel n'est pas.
 
 I should be LF rx qrv from Wasilla Alaska from the 24th-28th August if Im allowed to carry electronics onto the flight.
Laurence OJ11 Singapore (still)

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> From: roelof@ndb.demon.nl
> To: rsgb_lf_group@blacksheep.org
> Date: Wed, 9 Aug 2006 18:19:41 +0200
> Subject: LF: Re: 134.1Khz
> 
> Hello Laurence,
> 
> Glad to hear the design is working fine. Though there are now more than 120 
> around, as far as I know, it is the first one in Asia!
> 
> >> The only difference to the  original design is a slightly longer (cap) 
> >> aerial, added another few cms there,  and the inter-stage coupling 
> >> increased to 680pF from 560pF, only because thats what they have and not 
> >> to improve the LF side <<
> 
> This value is not very critical, but it should be in the order of > 100 nF 
> (0.1 µF) to achieve good VLF performance. 680 pF is a little on the low 
> side, I guess.
> 
> Adding a few cm length to the PCB antenna does not make much of a 
> difference.
> Doubling the size gives only 3 dB(m) more signal. It has been designed to 
> prevent overload of the receiver, but again nothing critical.
> 
> I am following your endeavers with great interest.
> 
> Best regards,
> 
> Roelof Bakker, pa0rdt
> 
>  
> 
>

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