Hi Luis,
Am 28.04.2015 10:34, schrieb VIGILANT Luis Fernández:
The closer station is Maxi
EA5CV. But he lacks a good Rx and antenna for MF
As long as the frequency of the RX is stable, it should work well. A
deaf RX can produce good results if the input signal is strong, you
know. For example, if he has a IC706 and a dipole for the 40m band, he
could make a T antenna out of the dipole, with a resonated
tuning/matching. This should provide enough signal strength and prevent
QRM / RX overload due to the spectrum limitation.
Unfortunately there is no
interest at all in the local hams for activities other than DX pileups
in HF
599!
But i think there are good chances to find new stations in EA! You just
need to search them actively. For example: Use the WSPR map, select all
bands and 24h, and see which station is active in EA. Then contact
him/her by qrz.com and ask for a cooperation, generate some motivation
to try something really new and exciting... If you contact such a
station, you know that it is active, it has a internet connection and a
running PC and knows what WSPR is. Then it is more likely to get a
positive feedback. Maybe it's better to focus on stations being active
on the lower bands rather than 10m or so.
I just made the test and found 14 from EA and 2 from CT :-)
If you decide to find one from EA, i will go to find one from CT. I
know it works because i have done it in the past, on LF :-)
and summit activations on 40m
during weekends. Ah! .... and some digital voices modes too
Beeing outside the shack is a good first step! But 40m is the wrong
band ;-)
My best reference is my own Rx
site at 7Km using MiniWhip and Perseus + SDR-Console V2
which provides up to 6 VFOs
sending each the audio stream to a different decoder
The nice side of QRPP is that
any small change worth the efforts. And there is plenty of room for
improving !
Oh yes indeed, i also noted that it is easier to improve the signal by
20 dB if you are starting at 1 mW TX pwr rather than 100 W :-)
Tx running 7/24. Water cooling the 2xBS170 but
it worths !!! ;-)
Yes, a BS170 is a good choice for a 3.3V output and it also has a very
low input capacity. It was my first idea to use a BS170 for the
Raspberry project too. But actually i find that a ICL7667 is a better
choice, even if the output is 4*f, i.e. ~ 1900 kHz for MF.
My 12V 100W PA is using an ICL7667 as the MOSFET driver (2x IRFZ48N),
so you can use your
QRPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP signal and
realise a (power) gain of > 40 dB :-)
Did you measure the RF current into your loop? Is the loop vertical or
horizontal? What is the height above ground?
I recommend to watch the antenna current because at higher power
levels, the C can warm up and detune the loop. The resulting mismatch
will then reduce the power taken from the PA...
Nice hobby :-)
73, Stefan
73 de Luis
EA5DOM
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