Hi Stefan,
a step attenuator may be a good solution in order to adjust the signal levels
deênding on QRM / QRN / signal.
73, Rik ON7YD - OR7T
________________________________________
Van: [email protected] [[email protected]]
namens Stefan Schäfer [[email protected]]
Verzonden: woensdag 20 juni 2012 19:00
Aan: [email protected]
Onderwerp: Re: LF: RE: Test signal needed
Hi Rik,
Am 20.06.2012 08:28, schrieb Rik Strobbe:
> About the TX antenna used as RX antenna: that often works fine if you do not
> overload the RX (BC at 525kHz+). I always use the 20dB attenuator of my good
> old TS440 to RX on my 11m high / 25m ling Lazy-L antenna.
Well, didn't measured yet but i think the transmit antenna is very
selective too. Anyway the signal levels may be to high in the near BC
region.
I've checked the filter curves in my small active antennas. Both, the
ferrite and the E field antenna are resonated, the E field antenna uses
a L to ground in front of the first gate.
These are the curves:
Active ferrite antenna: https://dl.dropbox.com/u/19882028/MF/MFferrite.png
Active E field antenna: https://dl.dropbox.com/u/19882028/MF/MFactiveE.png
The main aspect is to filter DLF at 153 kHz which causes much trouble
here...
Also my receiver is selective it selfe. As i said, 500 kHz is already 30
dB down...
> As long as the band noise is above the RX noise you won't loose any
> sensititity.
>
That's clear. But "band noise" is not so easy to find here. It's always
the question what the man made noise part is. However this seems to be
less critical on MF than on LF, as others already said..
73, tnx, cu
Stefan/DK7FC
> 73, Rik ON7YD - OR7T
> ________________________________________
> Van: [email protected] [[email protected]]
> namens Stefan Schäfer [[email protected]]
> Verzonden: woensdag 20 juni 2012 0:44
> Aan: [email protected]
> Onderwerp: LF: Test signal needed
>
> Rik, MF,
>
> Right now i'm testing the TX antenna as a RX antenna. This works much
> better than expected. A 10 dB attenuator is needed but no problem. Maybe
> you can give me a test signal again on 502 kHz, or someone else?
>
> It looks like the QRN is much lower on that antenna. That means that
> many of the crashes during my CQ calls have been charged rain drops that
> were falling on the E field probe, just my guess.
>
> I will listen another 20 min. on 502 kHz and apprechiate any test
> signals from amateurs.
>
> 73, Stefan
>
> Am 19.06.2012 23:53, schrieb Rik Strobbe:
>
>> actually 501.2kHz.
>> Stefan, I have replied to your CQ several times, but no luck.
>> You are 579 with the usual QSB.
>> I am running 150W into a 11m high / 25m long lazy-L antenna, estimared ERP
>> abt 1W.
>>
>> 73, Rik ON7YD
>>
>> ________________________________________
>> Van: [email protected] [[email protected]]
>> namens pa3abk [[email protected]]
>> Verzonden: dinsdag 19 juni 2012 23:30
>> Aan: [email protected]
>> Onderwerp: Re: LF: CQ on 476.5 kHz CW
>>
>> Lsn fer OR7T on 502 pse
>> Jan/pa3abk
>>
>> On 19-6-2012 23:20, Stefan Schäfer wrote:
>>
>>
>>> just in case someone wants...
>>> I will call until 22 UT if no one replies...
>>>
>>> 73, Stefan/DK7FC
>>>
>>>
>>>
>>>
>> --
>> pa3abk<-> dordrecht jo21it
>>
>>
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