Re: QDX 40/20/10 Variation
Jon,
There have been discussions and simulations of these BPFs. Many previous posts in the archive.
It is made difficult because there are stray capacitances and, in one case (in the very similar
By
Alan G4ZFQ
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#105326
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Re: QDX 40/20/10 Variation
Also new but I've been going through much the same sort of thinking.
I think the reason that the theoretical BPF frequencies are too high is because there is parasitic capacitance in the circuit as
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Chris, G5CTH
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#105325
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Re: Obsessive QMX tracking
Hi Randy, all
A topic which comes up often.
Our nearest FedEx depot is 250km away in the city of Izmir. It's not like
in US where you have a FedEx office in every town. So to get to FedEx they
have
By
Hans Summers
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#105324
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Re: 50w PA high input SWR
Glenn,
being OT here already, I just add that for that reason I added a 6 dB pi attenuator at the 10 W linear PA input. Thus still having 20 dB gain and better than 12 dB RL.
73 Bojan S53DZ
>
>
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Bojan Naglic
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#105323
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QDX 40/20/10 Variation
Good Morning,
I'm a newbie to this forum, I'm no EE and less than a year as a Ham. In
that context I will ask this question...
I'm interested in building a QDX but feel that a 40/20/10 version of
By
Jonathan Halterman
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#105322
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Re: Obsessive QMX tracking
GM Randy,
In my case the Tracking lagged arrival by about 3 days and quickly got caught up at delivery.
It seems that ¡°shipped¡± means a label was created, after that I think that they loose it,
By
KK4ITX John
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#105321
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Re: Software for Hobby RF Design?
Hans:
Have you shipped our order, yet?
HIF
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Leland Lannoye, W9HIF
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#105320
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Re: Software for Hobby RF Design?
Would like to know where this goes as well. So far, I can envision multiple signals and the like, bit such things have always fascinated me.
HIF
By
Leland Lannoye, W9HIF
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#105319
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Obsessive QMX tracking
My QMX kit was marked "shipped" on July 14 and at the same time FedEx
emailed me a tracking number. Checking the tracking status showed that
FedEx was awaiting the package. This status has not changed
By
Randy
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#105318
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Re: Software for Hobby RF Design?
Going a bit further OT:
I wonder what you guys think of the Kostas SV3ORA crystal oscillator
circuit http://qrp.gr/multiosc/index.htm which oscillates several crystals
at the same time? He took some
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Hans Summers
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#105317
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Re: New assembled High Bands QDX went into smoke
Hans,
Thanks for that info!
I am pretty certain QMX will outperform uSDX by a good bit!
You are off an excellent adventure here and we all are eager to see your
results!
JZ KJ4A
By
John Z
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#105316
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Re: New assembled High Bands QDX went into smoke
Hi John
I agree, and were this not the case, everyone would be using EER for ham
radio transceivers.
Practically speaking I measured a 37dB control range over the RF amplitude,
without magic; and a
By
Hans Summers
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#105315
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Re: New assembled High Bands QDX went into smoke
Willie, I am still working on this and do not have a finished response for
you yet.
I have added an "AM modulator" to my basic QDX amplifier simulation. I set
the power supply voltage to 6 volts and
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John Z
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#105314
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Re: Software for Hobby RF Design?
I've used SimSmith to model filters and then play with component values to see how changes in value make a change in the plot in order to learn what modifications I need to fix my filters.
SimSmith
By
Bob Benedict, KD8CGH
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#105313
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Re: Software for Hobby RF Design?
I believe it is not an OR but an AND situation.
There are times when building is a better choice than modeling (though I would challenge that the "model" is in your head and needs to be built to
By
Evan Hand
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#105312
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Re: Software for Hobby RF Design?
Chris, LTSpice, like any simulator, depends on a reasonably accurate model if it hopes to represent something near actual behavior of a circuit. This becomes more and more difficult as you go higher
By
Steven Dick, K1RF
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#105311
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Re: 50w PA high input SWR
Sorry Hans.I actually meant the 10w PA. Didn't read the thread title correctly.?Glenn?Sent from my Samsung Galaxy S7 smartphone.
By
Glenn
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#105310
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Re: Software for Hobby RF Design?
Hello Hans,
- Now I will don my asbestos suit because I know nobody will agree with me...
I should not be too certain about this statement.
At least I do agree for sure.
The same applies to antenna
By
Roelof Bakker
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#105309
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Re: Software for Hobby RF Design?
Hans,
No flames from me. Just a gentle admonition to a good fellow to open eyes
just a bit wider and see the complementary value that bench work and
simulation bring to the art and science of EE. It
By
John Z
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#105308
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Re: Software for Hobby RF Design?
Hi Cris,
Mayby MicroCap 12 is an idea.
It is free of charge now.
73's Jacques PA3EVZ
Op 18 jul. 2023 09:28, om 09:28, "clansd via groups.io" <clansd@...> schreef:
By
Jacques PA3EVZ
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#105307
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