Re: #ubitx-help Strong Audio Tones in and outside audio receive passband
#ubitx-help
Thank you for the clarifications. I’m all in for mods, changes and improvements to this kit radio because that’s where the fun is. But this post is cringe worthy if it affected the radios on a
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Joe Puma <kd2nfc@...>
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#41185
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Re: BITX QSO Afternoon/Night, Sunday, February 4, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
7.222 seems clr. Listening for a few then I will call some.
--
David
?N8DAH
Kit-Projects.com ( http://www.kit-projects.com )
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N8DAH
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#41184
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Re: Toroids winding information
#ubitx
Hi! I have checking with a magnifying loupe looking for broken copper tracks or any strange looking components. I have unsoldered and redone t11 and t10
i have resoldered all bits that looked poor
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César EA3IAV <Cesarleon@...>
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#41183
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Re: #ubitx-help Strong Audio Tones in and outside audio receive passband
#ubitx-help
For anything this complicated, a few units will fail in the field, if only due to rough handling through the mails.
The uBitx count is now up in the thousands.
Most uBitx's just work as delivered, no
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Jerry Gaffke
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#41182
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Re: BitX40 v1.27.7 SPOT mode
The CAL VALUE x 100 represents the offset (in Hz) that we need to apply to
the nominal VCOA frequency (875 MHz) in order to get the correct output
frequency.
So the ppm (parts per million) value can
By
Allard PE1NWL
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#41181
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Re: Toroids winding information
#ubitx
My idea would be to divide and conquer.
First step, see if you get proper quiescent currents through the IRF510's.
Put an ammeter in line with 12v supply for the IRF510's,
turn RV2 and RV3 to the
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Jerry Gaffke
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#41180
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Re: BITX QSO Afternoon/Night, Sunday, February 4, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Get well soon John. Listening to the top end of 40M right now and it's chock full of AM Rally stations all over the place from 7.250 to 300. I'm QRV on 7.240 for traffic and a possible substitute
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Tom VE3THR
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#41179
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Re: #ubitx-help Strong Audio Tones in and outside audio receive passband
#ubitx-help
I’ve been following this post. What does this all mean for a beginner who is waiting on a uBitx? Is there a problem with original design? Are these strong audio tones noticeable or interfering with
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Joe Puma <kd2nfc@...>
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#41178
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Re: ubitx receive audio troubleshooting
So in order to have an oscillation, you have to have a closed loop with a gain greater than one at the oscillation frequency
Since your squeal begins when you turn the vine control up, and then input
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Gordon Gibby <ggibby@...>
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#41177
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whistles in receive
I am sitting here reading some of this information and studying the new technology.? When I was young (at leas 50 years ago), solid state technologies were either in their infancy or still a dream.?
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Leland Lannoye
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#41176
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Re: Second batch of uBITX shipping?
#ubitx
Where did mine December 15th and got it about a week ago
Andy KM4TRT
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KM4TRT
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#41175
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Re: ubitx receive audio troubleshooting
My mistake. I meant TDA2822 chip.
Craig
KC2LFI
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radiodoc43
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#41174
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Re: ubitx receive audio troubleshooting
Where do you have a TPA 2016 chip?
The uBitx does not use that.
[image1.png]
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Gordon Gibby <ggibby@...>
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#41173
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Re: #ubitx-help Strong Audio Tones in and outside audio receive passband
#ubitx-help
Bingo!
See this ceramic resonator on Mouser:? pnum??81-CSTCE16M0VH3L99R0
Same physical size as what's on the Nano, I didn't see any quartz crystals that small.
Tolerance of those Murata parts is
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Jerry Gaffke
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#41172
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Re: #ubitx-help Strong Audio Tones in and outside audio receive passband
#ubitx-help
So, moving the Nano 8" away did away with tones in the crystal filter passband,?
which would be the ones of most concern to folks here in the forum
But you still see tones coming through the
By
Jerry Gaffke
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#41171
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Re: BitX40 v1.27.7 SPOT mode
OK, great! One other question...what is the relationship between the "PPM" calibration value and the "CAL VALUE" in line 43?
=Vic=
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Vic WA4THR
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#41170
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Re: #ubitx-help Strong Audio Tones in and outside audio receive passband
#ubitx-help
Ah, very nice that you were able to do all of this, and document it so well.
See my comments inline with your original text below
?
By
Jerry Gaffke
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#41169
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Re: #ubitx-help Strong Audio Tones in and outside audio receive passband
#ubitx-help
Not 100% sure but popular thinking indicates the "crystals" on smaller Arduino boards are actually ceramic resonators.? If this is true then it should be possible to use capacitence to pull them
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Arv Evans
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#41168
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Re: uBITX drive level..
#ubitx
Tilman and all,
Per, I think, Raj's suggestion, I change R63 to 11 ohms, and that seems to work well.
0805 parts fit on 1206 pads, and power dissipation is not an issue with an 0805
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Rod Self <km6sn@...>
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#41167
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Re: uBITX Firmware (CEC) 0.30 released (Test version).
#ubitx
Thanks for fast ansver, it is working.
In next days try to conect to pc. if it working with n1mm.
And with mmvari. This program using for digital and for contest.
Use this
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matjaz
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#41166
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