Re: LF: L400B LF engineering

[Knight Ao <ja10xx@yahoo.co.jp>]

Hi Laurence,

Thanks for the useful info.  I might try to insert a LPF or trap between

the probe and the FET.  There are several 100kW-500kW BC stations

located nearby my location.  

GL & 73's,

Yas

----- Original Message -----
From: Laurence KL7UK <hellozerohellozero@hotmail.com>
To: rsgb_lf_group@blacksheep.org
Date: 2012/9/18, Tue 11:05
Subject: LF: L400B LF engineering

Hi Yas and greetings from Calgary Alberta.

Yes the L400 has a 3 inductor series  single 10pf cap, and 2 resistor filter match prior to the 5457 Fet and 3904 driver (fm memory) . I'm being canny as I'm sure its a copyrighted design but significantly improves my situation here plagued with 50Kw 550/650/750/1430 (1Kw) blowtorches. - it has a large output and drives my 4 way splitter ok. Noise fig wise given the 10M in and other shunting cap components it can't be brilliant but the LPF function reduces the non linear nature of the FET when present with mulitple 3dBm or worse signals. This is my second L400 - the first one was dragged miles on Interstate 70 and still survived...

Laurence VE6/KL1X Calgary AB

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Date: Mon, 17 Sep 2012 16:04:09 +0900
From: ja10xx@yahoo.co.jp
To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: 136 overnite

Hi Laurence,

Good to know your L400B is working well.  Is there much difference

between L400B and PA0RDT-like mini-whip in terms of influence

from BC stations?   Seems L400B has a BC trap or low pass

filter. 

Anyway, look forward to your coming activities as there ain't much

movement here in the pacific region.

73's,

Yas

----- Original Message -----
From: Laurence KL7UK <hellozerohellozero@hotmail.com>
To: "rsgb_lf_group@blacksheep.org" <rsgb_lf_group@blacksheep.org>
Date: 2012/9/17, Mon 11:09
Subject: RE: LF: 136 overnite

Thanks Yas - yes I should have known given the CGM  carrier signature!

. I was working on Rx stability but glad to see Japan coming thru so well - the aim is to lock both tx and rx to GPS references and we are getting there -


I was using a LF Engineering L400B Omni probe at 50ft for info with R75 doing the hard work. It wasnt that quiet as we had a strong weather system passing thru South Central Alaska -

Yes Im looking to be tx/rx QRV this end, probably not complete till the middle of October -  and just a few more rx changes and new driver, plus issues in keeping the loop antennae up in the strong winds with flimsy trees, but its coming together after nearly 6 years of not being on Tx.  The new cables to the Tuner were laid yesterday in the forest, and Im testing a "short" Beverage that is looking over the North Pole - it appears nice and quiet, but not  that quiet that it worries me.

Cheers
Laurence KL1 X  WE2X P Q
Wasilla AK

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Date: Mon, 17 Sep 2012 09:42:43 +0900
From: ja10xx@yahoo.co.jp
To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: 136 overnite

Hi Laurence,

It's JA1CGM.  Guess he used QRSS60 or so while your grabber

was set to QRSS120 slow on Argo.   Any plan on QRV from your

end for JA/VK/ZL?

Look forward to your transmission.

73's,

Yas - Tokyo (JA8SCD)

----- Original Message -----
From: Laurence KL7UK <hellozerohellozero@hotmail.com>
To: "rsgb_lf_group@blacksheep.org" <rsgb_lf_group@blacksheep.org>
Date: 2012/9/17, Mon 02:56
Subject: LF: 136 overnite

Signals seen overnight - think this is from JA? My Antennae was on Omni and too late for Eu