Wow, so I just ordered 490 boards for AU$15. that is $0.03 a board.
I will give theses away free, just $3.50 postage DX, can be combined with other boards too...

Ill include it also free with a LPF boards when they arrive are available.

<VK4PP 45Mhz Filt rev.03_b.PNG>??<VK4PP 45Mhz Filt rev.03.PNG>??

Thanks to all those who are working on this.

73 Nick VK4PP

What's the reason to? set-up the Si5351 to maximum drive @ "8 mA" ,3.3 V (Output Driver close to 50 Ohms at 1.65V per IBIS models ) just to send through a? series resistor, then to a? 50 ohm 6 dB pad?
I was confused, and even more so now? from Kee's post on V4 schematic with increasing series resistance before the 6bB pad ,rather? than decreasing Si5351 drive and winding transformers to match impendance.?

Flame Suit On.? Just wishing? to re-cap the well head so all may benefit from the refined uBITX .
Regards,
Gary AG5TX

If you have room enough I would look to reasonably efficient wire antennas
such as a G5RV, Doublet and I have seen a very cheap new small tuner from
MFJ, don't remember the exact model, I think it is prices at 50Usd.

Il 09/set/2018 16:29, "David Posthuma" <davep@...> ha
scritto:

There have been many posts regarding end fed antennas. I hope these posts
were helpful.

My favorite portable antenna are various loops, either
full-wave loops, quads, or Miniature Magnetic Loop Antennas. Why do I
like
loops:


1. Because they are a closed circuit resulting in very low noise, far
less than a dipole, verticle, or end-fed wire (NOTE: You can't work
what
you can't hear)
2. Because the can be polarized vertically for low-angle radiation,
horizontally, or even a hybrid of these
3. Because they are easy to build and match to a 50-ohm coax

But for portable operation, nothing beats a Minature Magnetic Loop
antenna. This is because it is light-weight, directional, and can
literally
sit on the ground and still work perfectly well!

I wrote an article about Miniature Magnetic Loop Antennas for the
Elecraft.com team way back in 1999 when they were not yet so popular
(i.e.,
I was a builder of the early K2 and beta tester for the 100 watt linear).
Check it out at
.
You can build these antennas with materials from any home improvement
store. I hope they inspire some antenna building from among the
uBitx building family.

David Posthuma, WD8PUO

with rearranged low pass filters and the additional 45 MHz filter, CW operation is healthy enough to operate.

Hi Mark:
Success I used the 3.5 tft file worked, I am puzzled why this worked , dimensions are for 3.2 display,? the display is different than the ones I have seen on the group, but I like the format looks great thanks alot.
73 Ross Bell K7RSB

On Sep 11, 2018, at 19:44, Bill Cromwell <wrcromwell@...> wrote:

Hi,

Just to be clear, Warren IS talking about SSB operation when talking about the IMD products. That is a remaining issue. But with rearranged low pass filters and the additional 45 MHz filter, CW operation is healthy enough to operate.

It will probably not be very long before the IMD issue gets resolved. That is how open source projects are supposed to work we have been seeing this open source project do exactly that.

73,

Bill KU8H

On 09/11/2018 05:53 PM, Warren Allgyer wrote:
With the PA filters removed from the motherboard and constructed
externally with two relays per filter and better layout and isolation,
the harmonics on all bands are compliant with the existing filter
component values. With the addition of the R27 45 MHz filter with a 12:1
impedance transformer between the filter and the following mixer, my
uBitx is also now compliant for spurs. What remains for compliance is
confirmation of appropriate levels of intermodulation distortion.

There is no FCC or ITU standard for intermodulation distortion. There is
a standardized measurement procedure. Chapter 25 in the ARRL Handbook
details it. But what comprises an acceptable level is left to equipment
suppliers and specifiers. IMD is measured by putting 2 audio tones
within the 3 KHz SSB passband and generally 1 KHz apart at equal levels.
The resulting sideband signal is examined on a spectrum analyzer and the
level of the mixed products of the two tones is measured and compared to
the tone peaks themselves. It is generally accepted that the 3rd and 5th
order products should be a minimum of 24 dB below the level of either
tone. Military specifications often require as much a 36 dB difference.
IMD generally improves as you reduce power and gets drastically worse
with over driven RF stages. I generally consider the power level which
gives at least 24 dB of 3rd and 5th order suppression to be the maximum
useable level and this is the test standard used by many equipment
manufacturers.

With that as background I set about testing the now compliant radio.

Unfortunately there seems to be no power level at which 80 and 40 meters
can achieve 24 dB in my radio. On 80 meters the best I could achieve as
I varied the power level from 100 mW to 10 watts was 19 dB. And that was
at 100 mW. Audio input in this case was 30 mVrms and reducing it by as
much as 10 dB did not improve IMD. It only limited the maximum power
that can be achieved. Power level in these tests was varied with RV1.

On 40 meters the best IMD achievable was 12 dB.

20 meters was the first band where I could achieve a 24 dB reading and
that was at 1.5 watts out. At any higher power level IMD rose
dramatically. At 5 watts it was 16 dB.

I stopped my tests at this point. Such levels are not useable in my
opinion and only get significantly worse as external amplifiers are added.

WA8TOD

--
bark less - wag more

With the PA filters removed from the motherboard and constructed
externally with two relays per filter and better layout and isolation,
the harmonics on all bands are compliant with the existing filter
component values. With the addition of the R27 45 MHz filter with a 12:1
impedance transformer between the filter and the following mixer, my
uBitx is also now compliant for spurs. What remains for compliance is
confirmation of appropriate levels of intermodulation distortion.

There is no FCC or ITU standard for intermodulation distortion. There is
a standardized measurement procedure. Chapter 25 in the ARRL Handbook
details it. But what comprises an acceptable level is left to equipment
suppliers and specifiers. IMD is measured by putting 2 audio tones
within the 3 KHz SSB passband and generally 1 KHz apart at equal levels.
The resulting sideband signal is examined on a spectrum analyzer and the
level of the mixed products of the two tones is measured and compared to
the tone peaks themselves. It is generally accepted that the 3rd and 5th
order products should be a minimum of 24 dB below the level of either
tone. Military specifications often require as much a 36 dB difference.
IMD generally improves as you reduce power and gets drastically worse
with over driven RF stages. I generally consider the power level which
gives at least 24 dB of 3rd and 5th order suppression to be the maximum
useable level and this is the test standard used by many equipment
manufacturers.

With that as background I set about testing the now compliant radio.

Unfortunately there seems to be no power level at which 80 and 40 meters
can achieve 24 dB in my radio. On 80 meters the best I could achieve as
I varied the power level from 100 mW to 10 watts was 19 dB. And that was
at 100 mW. Audio input in this case was 30 mVrms and reducing it by as
much as 10 dB did not improve IMD. It only limited the maximum power
that can be achieved. Power level in these tests was varied with RV1.

On 40 meters the best IMD achievable was 12 dB.

20 meters was the first band where I could achieve a 24 dB reading and
that was at 1.5 watts out. At any higher power level IMD rose
dramatically. At 5 watts it was 16 dB.

I stopped my tests at this point. Such levels are not useable in my
opinion and only get significantly worse as external amplifiers are added.

WA8TOD

>>Did you buffer all three outputs in your test?? And measure the buffered one only or all three?

All three with the 74AUP wich are one inverter per package.

>>I don't have access to 74LVT04 but used 3 x 74LVC04's (SOT single versions)

I didn't try the hex inverter part (6 inverters per package).? I suspect that needs testing?
as you run into the same issues of common busses on the die for power.? So that part
could (untested) also have cross talk.

Of course with fast rise/fall time transistions the layout should look like VHF/UHF
ground planes and top pour of ground copper.??Bypassing is also important and
watch for ground loops.

Allison

Hi All:
I just received myNextion 3.2 basic today, I cannot get any files to upload with the with the SD card (formatted with fat32 one tft file) or the editor. The editor send a connect failed: forced interrupt error and the sd card error: Model does not Match?device model: NX48320T035_011R. Possible I am using the wrong version software? Not finding any with help with google. Any help is appreciated
Thanks and 73