Ciao Marco, LF
Thank you for the reports. It is nice to be on air again in MF !
The PA current is 5A@14V, so no more than 70w to antenna. But here the antenna
is made by a 11m vertical + top cap
top loaded and top feeded in the terrace of 80m height buiding tower. The
ground side of the PA runs down to
ground those 80m and is part of the antenna, running just corrent, not high
voltage. This is almost what
Rik ON7YD describes here http://www.strobbe.eu/on7yd/136ant/#IndTop
Noted some problems with the current protection circuit which triggered at
23utc. From that time to about 5utc
I was running just 500mW from U3 bypassing the PA. BTW, I keep transmitting
during daytime. Looks like last
Winter, when I could get decodes at daylight from some stations at Germany and
the UK
Pity I still don't have a proper transverter to work JT9. But will try to join
the QRSS and CW party next days
73 de Luis
EA5DOM
-----Mensaje original-----
De: [email protected]
[mailto:[email protected]] En nombre de [email protected]
Enviado el: jueves, 27 de octubre de 2016 22:22
Para: [email protected]
Asunto: R: RE: ULF: A new step on the large ULF coil...
Hola Luis,
tonight you are booming on 630m wspr!
I don't remember if this is the first time I listen to you, but is really a
booming signal abeit the distance.
Unfortunately bad
copy from Stefan (or better optimum if he's running qrp) if the stated power is
correct
GL
Marco IK1HSS
----Messaggio originale----
Da: [email protected]
Data: 27-ott-2016 11.40
A: "[email protected]"<[email protected]>
Ogg: RE: ULF: A new step on the large ULF coil...
Amazing work Stefan !! :-O
I bet you have constructed some kind of support (like a lathe) which
lets you rotate the pipe easily and wound the coils . Right ?
This is getting really heavy and the quality of coils looks very nice
and repeteable ...... at least five times ! ;-)
Dumb question: Why do you get different inductance values when
resonating it with antenna equivalent capacitor and when measuring
current at 273V AC / 50Hz ??
Shouldn't be inductance a constant value ? ...... or I'm missing
something obvious :(
Good luck with the 6th floor. Seems that there is no room for a 7th, so
that's why you mentioned the variometer
73 de Luis
EA5DOM
________________________________
De: [email protected] [mailto:owner-
[email protected]] En nombre de DK7FC
Enviado el: miércoles, 26 de octubre de 2016 19:06
Para: [email protected]
Asunto: Re: ULF: A new step on the large ULF coil...
Hi ULF,
It's just a few weeks ago, now the 5th stack is wound on the coil:
https://dl.dropboxusercontent.com/u/19882028/ULF/20161026_185804.jpg
The DC resistance rose from 445 Ohm to 572 Ohm.
The measured resonance frequency (using the antenna equivalent C in
the shack) dropped from 3.667 kHz down to 3.208 kHz. That should be
about 4.92 H.
Measured at 273V AC / 50 Hz, i'm getting 197 mA, so the actual
inductance is 4.0 H.
A 6th stack and a variometer part is needed!
73, Stefan
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