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Re: New SI5340-based RF Board in development
That oscillator on a small daughter card would be a great way to try this and other oscillators like it. Also¡­ I did finally find FFs that operate in the GHZ region. I ordered a couple dozen so may
By K9HZ · #34076 ·
Re: Strange 15 happenings
That should have been 15M¡­ Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois Owner ¨C Operator
By K9HZ · #34075 ·
Re: Strange 15 happenings
I have not looked at the code, but when we were all discussing the TX output calibration, we were going to have it set up BAND (that is, a different calibration constant for each band¡­ this will be
By K9HZ · #34074 ·
Re: MF changes
Oh! Well PLEASE keep us up to date! Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ Owner - Operator Big Signal Ranch ¨C K9ZC Staunton, Illinois Owner ¨C
By K9HZ · #34073 ·
Re: MF changes
The oscillator could be anything you want to put on that oscillator board. Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ Owner - Operator Big Signal Ranch ¨C
By K9HZ · #34072 ·
Strange 15 happenings
I was having fun working DX on 20 and 17M's today. Saw activity on 15, made a few calls noticed output in SSB was low. SWR was perfect (Steppir) so I decided to play with TX attenuation. Changed from
By Tim · #34071 ·
Re: T41 Hilbert Filter Design
To clarify: in the 90/0 degree case, you still need to pass the data through the "0 degree" filter. Every FIR filter will impart a phase shift that increases linearly with frequency [will come back to
By Oliver KI3P · #34070 ·
Re: MF changes
Hi Rob- Here's an example of a power supply board.? The switching modules are really good! https://github.com/Greg-R/T41-2_Power -- 73 Greg KF5N
By Greg KF5N · #34069 ·
Re: MF changes
Hi Bill, I'm just about to start populating a Main board that has the SGTL5000 and the SPI driver onboard. I've also done away with the 3.5mm Jacks and replaced them with JST connectors, along with
By Rob G7WKE · #34068 ·
Re: MF changes
I like the idea of breaking the LO onto a daughter board that mounts to the RF board through header pins. That'll allow for more experimentation.
By Oliver KI3P · #34067 ·
Re: T41 Hilbert Filter Design
And, thanks for the comments, Terrance.? I agree with all.? Our posts crossed in the mail.
By Bob Larkin · #34066 ·
Re: T41 Hilbert Filter Design
Thanks Oliver for the response curves.? Interesting to see.? Also, I had missed the sampling rate? on the v50 curve being 24 kHz.? I added a note to the index page to cover that. Unless I am
By Bob Larkin · #34065 ·
Re: T41 Hilbert Filter Design
I made a production line of sorts and tested about 20 different Hilbert transform filters only to confirm what I learned during my DSP experiment days: "at a certain point, filter design is as much an
By Terrance Robertson, KN6ZDE · #34064 ·
Re: MF changes
I would be in for some pre-populated boards to play with. and eliminating the issue with audio hat would be much appreciated (caused me a lot of headaches!) as to plug in oscillator board would it
By Tim · #34063 ·
Re: T41 with Polar Modulation
OK, that's interesting because I measured 4.5 watts PEP with 30dB IM3 (40 meters). -- 73 Greg KF5N
By Greg KF5N · #34062 ·
Re: T41 with Polar Modulation
Greg,' I believe it was about 4W RMS. Al
By Albert Peter · #34061 ·
Re: MF changes
My apologies. I¡¯ve been on the road since before Hamvention and unavailable for the most part. I¡¯ll be back home as of Thursday AM and have a lot of catching up to do with orders from Hamvention
By K9HZ · #34060 ·
Re: T41 Hilbert Filter Design
For comparison, here are plots of the responses of the various versions of the Hilbert filters. Here's the version that is currently in the code (FIR_Hilbert_coeffs_45,FIR_Hilbert_coeffs_neg_45):
By Oliver KI3P · #34059 ·
Re: T41 Hilbert Filter Design
Thanks.? Great program, though it doesn't totally work in my version of Octave.? I made some edits to get it mostly working.? That explains one thing.? It looks like the narrow response cuts off
By Terrance Robertson, KN6ZDE · #34058 ·
Re: T41 Hilbert Filter Design
I posted the Octave .m files, the three sideband suppression curves, the coefficients for the 199 tap plus delay and the Hilbert design files.? They are at
By Bob Larkin · #34057 ·