Re: Spurs/Harmonics fixes for v4 based on v5 board design?
I did want to say the Axicom relays I'm not sure if they helped a lot at least with my less than adequate ability to measure at the moment with the rtl-sdr or scopt fft.
IMD seemed down a little within 0.75 MHZ away but the big harmonic at 21MHZ didn't seem to change.
I will also say you will have to perfect your desoldering skills to remove all 5 relays :)? I thought I knew how to desolder before I started... but clearly I was deluding myself.
I nearly gave up but watched a couple youtube video's and so someone much better than I doing it and managed to learn the way to do it with a simple suction vac and desoldering braid.. though I was really wishing I had one of those hakko electric vacuum desoldering tools :)
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On Tue, Jan 22, 2019 at 06:55 PM, Dave Space wrote:
I actually did replace all of the relays with axicom relays.? I bought some parts to build an external filter to see how that does (not due to arrive for a while).? I'm transmitting SSB when doing the test.
I also bought the parts to replace L5 and L7 not due to arrive for a little while either.? Any chance the mod suggested for the v5 board would solve this harmonic?
On Tue, Jan 22, 2019 at 06:43 PM, Jerry Gaffke wrote:
21.5mhz is the third harmonic of 7.15mhz, we can expect some trouble there,
though -20dBc is worse than I recall seeing on measurements posted here for other uBitx's.
Moving to the axicom relays might help this considerably, or any of the other mods
proposed for fixing the ubitx board layout issues in the transmit low pass filters.
Or could just add an external low pass filter between rig and antenna
when operating on 40 meters to fix this.
I'd guess you are transmitting in CW mode, which may be driving the final too hard.
You might try reducing the drive to the final at RV1, see if that helps.
Make a mark first so you can remember how it had been set originally.
Jerry
On Tue, Jan 22, 2019 at 05:43 PM, Dave Space wrote:
So I remeasured my ubitx this time with my oscilloscope FFT.? Not sure how accurate those are?
It shows a lot less spurs but does still show a spur only -20db down when transmitting at 7.150MHZ somewhere around 21.5MHZ or so (I didn't zoom in too far so plus or minus ~500khz .? (I tested connected to the scope through coax -40db attenuator).
It tends to confirm of the rtl-sdr which saw one about -30db down or so.? I didn't notice the large amount of IMD within 750khz range as I did with the RTL-SDR though there was a lot of noise (might have to up the averaging to see if I can filter that out).
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Hi Vic
I have made the bezels Vic I have flat ones for the 2.8 and 3.2" nextion. They are 3D printed. The Indian kit that I got used didn't have a bezel.
If you want one I will send it to you. These were printed a bright orange then lightly sprayed with black dollar store paint. They look like dark wood grain.
The larger bezel is on thingiverse if you have a 3d printer.
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Put the BITX40together with the 10-turn pot. Worked for
a few minutes and then phoey. At first I heard some 40Mactivity and was enthusiastic but then got some turn-on ver notice and after that I got a 40M running list of up-down frequencies. No more audio, no more reaction to the 10-turn
pot. The board and Raduino were nt touched.
On a whim, I changed the 10-turn pot for the one that came with the kit and the kit and still no audio. The skipping around in frequency is still there. I do not want to chase my tail around trying to find the problem. I expected a working radio like the uBitx was
when I put it in a box. I will sell the BITX40 for $60 shipped stateside. It's in
a "box" with the platform and front/back panels. Nosides or top. Only modification to the kit overall is that used a UHF connector instead of the BNC connector. NO mods to the board or the Raduino... It's all there ready to play with but I am at my age not ready to play with it. Anyone stateside interested? Will include the 10-turn pot, the unused BNC connector snd? the unused mic/ptt cables which were not connected. The mic parts will
also be included, the mic was not assembled...
Bob ¡ª KK5R
On Tuesday, January 22, 2019, 6:40:52 PM EST, Bob Lunsford via Groups.Io <nocrud222@...> wrote:
Just got the BITX40 today. I had the uBitx before and sold it to
a man who wanted to run digital. It was a dream to put together,
no problem whatsoever.
But the picture on the wire-up page for the BITX40 does not
show the same thing for the Raduino that I got today. I do not
want to assume too much but it seems the 5-pin connector
plugs into the 16-pin connector but it's not clear if it's to be
put in on one or the other end. The 16-pin connector is
labeled P3. Off to one end of the board is U3 which is a
3-pin regulator, it seems. I think I know where the 5-pin
connector goes but want to make sure...
Bob ¡ª KK5R
--------------------------------------------
Subject: Re: [BITX20] ubitx 40 Connecdtion
Date: Tuesday, January 22, 2019, 6:12 PM
Bob,
?BITX and BITX40 are different radios.? Which
do you have?
--
www.bitxmap.com
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?I did a quick search for LM386 audio amps and came up with this one. ? ?the more you buy, the lower unit price gets. ?Not a bad deal, with free shipping.
?I think it'll cost me a bit more to assemble such an item, even though I have a boatload of LM386 chips.
?its the caps and control, plus board that makes it that way.
?Though doing my own, I can set the gain from 20 to 100, and in between of course.A reasonable board to add audio if yours is blown....
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On Thu, Jan 24, 2019 at 4:30 PM Mvs Sarma < mvssarma@...> wrote: some cases, seller would supply along with Case. See this case from India. Nextion is shown for showing clarity? and not supplied. Thease are from vu3pop from India. I had seen them in Lamakaan amateur radio club annual eyeball meet 19/20 Jan2019
On Thu, Jan 24, 2019 at 3:14 PM Vic WA4THR via Groups.Io <vhklein= [email protected]> wrote: I am interested in the bezel around the Nextion display in the white case. Did it come with that case or did you get it somewhere?
=Vic=
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Re: Error in Ubitx Mic Amp circuit?
It depends on the value of the cap. Electrolytics have larger values and should be better on low frequencies, but others may be used. You may want to replace it, but you may want to lower R63 to have more gain. I lowered to 24ohm. However to increase average SSB power I have added a compressor, SL6270C at the mic input so I can just whisper with any dynamic mic and have a QSO instead of trying to increase average power talking speaking louder and likely producing more distortion.
Il 14/gen/2019 18:06, "Uwe , DF1UB" < jento23@...> ha scritto: Hi,
is there an error in the circuit of the mic amp or just the wrong Cap build in?
the cap C63 at the collector of Q6 should be 1? polarized, but on the board is a ceramic C.Is this the fault of low mic signal?
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On Thu, Jan 24, 2019 at 4:30 PM Mvs Sarma < mvssarma@...> wrote: some cases, seller would supply along with Case. See this case from India. Nextion is shown for showing clarity? and not supplied. Thease are from vu3pop from India. I had seen them in Lamakaan amateur radio club annual eyeball meet 19/20 Jan2019
On Thu, Jan 24, 2019 at 3:14 PM Vic WA4THR via Groups.Io <vhklein= [email protected]> wrote: I am interested in the bezel around the Nextion display in the white case. Did it come with that case or did you get it somewhere?
=Vic=
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some cases, seller would supply along with Case. See this case from India. Nextion is shown for showing clarity? and not supplied. Thease are from vu3pop from India. I had seen them in Lamakaan amateur radio club annual eyeball meet 19/20 Jan2019
On Thu, Jan 24, 2019 at 3:14 PM Vic WA4THR via Groups.Io <vhklein= [email protected]> wrote: I am interested in the bezel around the Nextion display in the white case. Did it come with that case or did you get it somewhere?
=Vic=
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Good Morning, ? How would a person go about ordering one of these little gems?? ? ? 773, Rocco ¨C WU2M ? Sent from for Windows 10 ?
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From: KE2GKB via Groups.IoSent: Thursday, January 24, 2019 12:56 AM To: [email protected]Subject: Re: [BITX20] 2 New kits in stock! ? Some more info on the AGC.
It has been designed to slot right onto the uBitx V3 and V4 board with one trace cut and the scraping of solder mask off 3 traces. Instructions on location and placement will be provided with the AGC.
It lines up So you can solder it directly to the board with no RF leads or coax needed! The only wire to be ran is a single audio line from the VOL-H side of the volume control to the board. The board includes a Choke to help keep RF out of the audio amp. There is also an S-Meter tap after the audio amplifier on circuit. Does need per unit calibration but has been proven to work rather nicely!
Below is a pretty render for your enjoyment.
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If you will only use the Raduino with a bitx remove the other 11 pins to prevent miswiring. Don¡¯t ask how I know this is a bad thing. ?
Mike Ai4ns?
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Aargh. And after I read your instructions, I still did it.?
Thanks everyone?
On Wed, Jan 23, 2019 at 10:17 PM Jack Purdum via Groups.Io <jjpurdum= [email protected]> wrote:
You cannot have any library in the Arduino libraries subdirectory that contains the string "-master" at the end of the primary file name. Although written for the JackAl system, the download at titled "Installing the Software", which is a zip file, should help you understand how to install the libraries properly. When unzipped, read the document titled Library Installation Instructions.docx. It explains how to install both Arduino and Teensy libraries and why they are installed as they are. You need to obey the rules stated therein. If you do, I think you compile problems will go away.
Jack, W8TEE
Attached is the log of my multiple attempts to upload a sketch to the Nano. I only see the power led lit on the nano. What am I doing wrong?
mike
ai4ns
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I am interested in the bezel around the Nextion display in the white case. Did it come with that case or did you get it somewhere?
=Vic=
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Some more info on the AGC. It has been designed to slot right onto the uBitx V3 and V4 board with one trace cut and the scraping of solder mask off 3 traces. Instructions on location and placement will be provided with the AGC. It lines up So you can solder it directly to the board with no RF leads or coax needed! The only wire to be ran is a single audio line from the VOL-H side of the volume control to the board. The board includes a Choke to help keep RF out of the audio amp. There is also an S-Meter tap after the audio amplifier on circuit. Does need per unit calibration but has been proven to work rather nicely! Below is a pretty render for your enjoyment. 
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Re: spurs & harmonics, whew!
please check the concerned band?? LPF (Post? linear). Analyse the filter components , for values , if you have any L C
meter on hand.
?
On Wed, Jan 23, 2019 at 11:52 PM Curt via Groups.Io <wb8yyy= [email protected]> wrote: I am going with Gordan Gibby's daughter board that just hosts 3 relays, mostly because my local club kitted this solution - and other than cutting traces there is little rework to the main board.? I need about 10 dB reduction of harmonics on 40 and 30 meters, and less on 80 and 20 meters to be in compliance.? (As there is reported variation in the Axicom relay approach, and different rigs require a different boost in rejection, it seems to not be the ideal approach to me - and I sense in quantity our approach costs less).?
I tried using a 45 MHz xtal filter between the bidirectional amplifier and mixer - every different way I could think of.? I even left both the series resistor and cap in place on the mixer side - no matter what I do I get a reduction of 40m CW transmit down to about 2 watts -- while no other band is affected.? At least one other rig in our batch is acting like this.? So when the final mixer is biased for CW 'direct PLL making RF' - it does not cooperate with changes on the IF port.? Have not yet tried LC filtering - don't know what it will do.? I need about 10 dB here also to filter the unwanted mixer spur on some of the higher bands.?
No other issues with my v4 transceiver.? SSB works nicely using an old electret microphone originally used with a 2m HT.?
Curt
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one can plug in the headphones before switching on and never use more than 10% or so of the volume control,and the chances of chip burning would be reduced.
I recollect , people are accustomed to13.8V, later think that 14 or 14.5 is marginally small.
we fail to understand the stress taken by TDA2822
On Thu, Jan 24, 2019 at 3:28 AM Jerry Gaffke via Groups.Io <jgaffke= [email protected]> wrote: Perhaps Bill's point was that pushing a stereo plug into a stereo jack
can somehow momentarily short one of the signals to ground.
A 4 ohm resistor between uBitx main board and the headphone jack would solve this
if that's of concern.
But I think all cases of momentary shorts blowing a TDA2822 involved a WX brand TDA2822.
We'll see if Raj corrects me on this one too.
Jerry, KE7ER
On Wed, Jan 23, 2019 at 12:41 PM, Jerry Gaffke wrote:
Maybe best to just make sure there isn't anything with a mono 3.5mm plug on it within easy reach.
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You cannot have any library in the Arduino libraries subdirectory that contains the string "-master" at the end of the primary file name. Although written for the JackAl system, the download at hamradiodesigns.com titled "Installing the Software", which is a zip file, should help you understand how to install the libraries properly. When unzipped, read the document titled Library Installation Instructions.docx. It explains how to install both Arduino and Teensy libraries and why they are installed as they are. You need to obey the rules stated therein. If you do, I think you compile problems will go away.
Jack, W8TEE
On Wednesday, January 23, 2019, 11:06:21 PM EST, Mike Short <ai4ns.mike.spam@...> wrote:
Attached is the log of my multiple attempts to upload a sketch to the Nano. I only see the power led lit on the nano. What am I doing wrong?
mike
ai4ns
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i suppose you are accustomed with arduino ide, Mike the files should be in a folder named as same ? the .ino file inside. ?once you plug in the nano, ? go to tools and configure the nano, and its com port. if the port is not recognized, perhaps you have to use the Ch340G driver.
later the port becomes visible. You may tick the right com port as indicated by your laptop. ?select programmer : arduino ide If these things are gone thro, ?perhaps no issue could be there.
all the best Mike ?regards sarma ?vu3zmv
?At times you have to select? atmeega328 old bootloadder .
Attached is the log of my multiple attempts to upload a sketch to the Nano. I only see the power led lit on the nano. What am I doing wrong?
mike
ai4ns
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Attached is the log of my multiple attempts to upload a sketch to the Nano. I only see the power led lit on the nano. What am I doing wrong?
mike
ai4ns
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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Yep I was thinking about hacking that trace up. have to search around to see if there is a ground but I couldn't find anything that looked near by on the schematic.? But maybe probing around might find something.? ? I'm hoping it wouldn't impact anything else except the spur.? What did you use to measure spurs on your board?
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On Wed, Jan 23, 2019 at 04:43 PM, Curt wrote:
Dave
I am thinking avoid drilling hole.? one must disconnect at R27 somehow to insert this new filter.? I think grounding C205 to some location near where you new filter will sit is most important - find a part connected to ground (use your DVM as continuity checker) and solder one end of a leaded cap there.? now find some way to place your 2 inductors together - could even be on a tiny piece of circuit board hacked into 3 islands, or a trace attached to TP13.? I am looking to try this mod myself but still thinking how I may do it.? After installing I need to verify it does not affect CW (like the xtal filter I tried) and then see if the mixer spurs are sufficiently reduced - I need about 10 dB per measurements we made at club building session.?
Curt
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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Mainly based on this review:
Seems like for $60 more you are getting a more rugged device with shielding.? The difference between the Pro and the standard is on the SDRPlay product page: just a steel case vs a shielded plastic case.
After looking at the specs of the RSP1A, you may be right.? Made the wrong choice.
Will see if I can exchange it.
Thanks,
Evan?
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_Dave_ AD0B
Bob Lunsford
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Vic WA4THR