Hi Marco, Chris,
Greetings from the lower end of the spectrum. It is quite silent down
here, no contests, no band plans, not even complaints about key
clicks!!!! (so relaxing), no pile ups, just the nature is speaking to me
from time to time. And ZEVS is whispering but i can't hear it so far.
I'm envious, up on the microwaves with just a few km of wavelength you
have so much bandwidth, you can tune down by 1 kHz and more, whereas i
would crash into the DC wall when attempting to try that. Also your
coils are so small, the antenna current so high, the voltages so low,
the ERP so high, and there are so many people daily.
However my phase is so stable down here and so reproducable :-) So i can
can talk very slowly or say just one word per day. And i'm diving below
the switch mode power supply QRM and inbetween the mains hum :-)
It all has its pros and cons. Anyway we have a nice hobby on the real
low frequencies.
I'll visit you again in the near future on 137 kHz. Maybe we can try
something like JT9 or QRSS?
73, Stefan
Am 02.06.2017 15:51, schrieb [email protected]:
Hello Chris,
yes I'm testing into a dummy load and getting troubles trepassing the
15kmW (thousend of mW) limit!!!
I drive with a reasonable waveform both the qrp TX and
medium power TX (and now the halfbridge tx) with an IXDD614 chip.
Will resist still in this microwaves area waiting that the oter folks
go to DC ;-)))
CU Marco
----Messaggio originale----
Da: [email protected]
Data: 2-giu-2017 15.14
A:<[email protected]>
Ogg: Re: R: LF: Re: I: Fw: For today the FETs survived...
Hello Marco,
My loading coil drifts as it warms up, but that's only when a kW or so
is run, not at low power. But I think you are testing into a dummy
load? I also had a poor drain waveform on one side of my push pull
Class "D", that was only cured by changing one of the 2 FET's (that
tested fine out of circuit). We "microwavers" are old school now
that
people are moving to DC toggled every hour or so ;)
Friday, June 2, 2017, 2:00:07 PM, you wrote:
Hi Alan,
and thanks for joining :-)
it's hard to believe at this stage that is correct to speak of "high
currents"..
The PA is an half bridge like
Andy's 700W but now I'm testing at low voltage: I see these problem
trepassing the 30Vdc supply level (and power is about 15W)..
Anyway will try with the "pulse rated caps" you suggested just in
case
my "low current" "low tension" ideas are wrong.
73 Marco
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