Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

Re: LF: Qrss3 beacon test

To: [email protected]
Subject: Re: LF: Qrss3 beacon test
From: Tobias DG3LV <[email protected]>
Date: Mon, 16 Feb 2015 23:28:04 +0100
In-reply-to: <[email protected]>
References: <[email protected]> <[email protected]> <[email protected]> <[email protected]>
Reply-to: [email protected]
Sender: [email protected]
User-agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0
Hi Mauro !

The FZ_02 mechanical filter can be easily inserted into a 50 Ohm receiving(!) system by the use of two 1:9 transformers (at Input and Output of the FZ-02) to match the 500 Ohm Input/Output impedances of the filter at the yellow wires! Use capacitors of the exact capacity [in pF] as printed at both ends of the filter for compensation. (I soldered the capacitors to the unused 18k-Ohm wires = red).
You will get a flat top of the attenuation curve and steep edges.

measured Attenuations at :
461.2 kHz -64.91dB
467.1 kHz  -3.10dB
473.0 kHz  -2.70dB
479.1 kHz  -3.48dB
485.3 kHz -63.62dB

used 1:9 Transformer : FT50-43 toroid, 10 turns of (flat) trifilar enamelled wire (AWG #26).

This filter is a good cure to all sorts of intermodulation and noise caused by out-of-band signals.

73 de dg3lv Tobias

Am 16.02.2015 um 22:08 schrieb IK1WVQ Mauro:
hi Luigi,
this is the schematic of my stupid receiver..
today I bought from Ebay a mechanical filter FZ_02 to clean a bit the
spectrum.

coming soon: a 20W TX (mosfet IRF510) for tests with "earth_electrode
antenna" (impossible for me to build a Marconi)

73 de Mauro IK1WVQ



Very interesting... Do you have  mord info Mauro?

Inviato da iPhone

> Il giorno 15/feb/2015, alle ore 22:28, IK1WVQ Mauro <[email protected]>
ha scritto:
>
> Hi Luigi,
> your signal is ok here in JN44CB.
>
> my antenna is PA0RDT
> RX is a simple NE602 mixer with a MF 455kHz(yallow core) front end ..
> no RF preamplifier, no audio postamplifier . directly to the MIC
input of PC !!
>
> 73 de Mauro IK1WVQ
>
>
>
>
>
> At 13:40 15/02/2015, IZ7PDX Luigi D. wrote:
>> Gm Mf ...
>> I have the pleasure to introduce my new  QRSS3 test beacon at
476.150 Khz in JN80PS.
>> 25 mt new Marconi antenna , 50 W.
>> Daily and night reports are welcome !
>> Thanks in advance.
>> Vy 73 de Luigi IZ7PDX
>>
>> Inviato da iPhone
> <argo_ik7pdx_0020.jpg>

<Prev in Thread] Current Thread [Next in Thread>