Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Hi!
Thank you for your comment and advice.
My friend have found the cause of spurious of 75 KHz.
He said the cause of spurious was the noise of VCC around 19 MHz of 0.15V.
As the result of the modifications of Bitx40 to reduce the noise, such as adding the big condenser and choke coil etc , the spurious level went down below of the criteria.
By this modification, my Bitx40 meets the criteria of the spurious of Japanese regulation.
So I am going to submit the application for obtaining the certification of Bitx40 from the relevant authority.
There?are two criteria for the spurious.
?? 1)? Baseband area :? under -40db of power of fundamental frequency
??????????? This?frequency range is the 2.5 x? occupied band of frequency of TX mode.
?? 2) Spurious area :? under -50db of power of fundamental frequency.
?????????? This frequency range is the out of Baseband area for super harmonic spurious.
The attached files are
? 1) The picture of noise of VCC
?2) The picture of Spurious of 50KHz/div after the modification.
?3) The picture how the modification were added.
73!
Akira
JJ1EPE
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Re: Homebrew from scratch
#ubitx
Here is the finished board with the on board Arduino and Si5351 alongside an original uBITX.
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Re: TX frequency? of uBitx at CWL and CWU mode
#ubitxcw
Hi!
Thank you for your advice and comment.
Firstly, I did not consider that frequency displayed on the commercial rigs is TX frequency even though frequency of uBitx is RX.
But I am still wondering why the difference of frequency between my ICOM transceiver and uBitx is 1.5Hz but not off set .
1.5KHz might be double of 700 or 800 Hz off set.
I think many uBitx user have been making the contact on CWL or CWU?mode by uBitx.
So there is something I have not understood about offset of CW.
I would like to examine the cause of the frequency difference of 1.5KHz.
73!
Akira
JJ1EPE
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In traditional rigs and in DDS there is a variable capacitor that is used to precisely and easily adjust the BFO or the DDS output. In dongles it can be easily done via the software. Using the 10mhz reference signal or the carrier of any SW broadcast is a matter of seconds to adjust it precisely. As the BFO in my Ubitx is off around 150hz, I wish to know whether there is an easy way to adjust it. My rig is Ubitx ver. 3 and original firmware.
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Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
OK! connected up the bitx40 with Raduino.
Yes, there are spurious as reported. The spurious distance from carrier varies with frequency.
All the spurs all come together and disappear at near 7.2 Mhz. This is mixing of harmonics but
cant remember the maths.. Jerry and others had worked it out.
I will try out a filter that I had wired on some board but donno where I kept it!
Raj
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Show quoted text
At 02-07-18, you wrote: Raj,
thanks for testing, but the issue that Akira san reported, is with BitX40,
not ubitx.
If possible, could you please repeat the same check with BitX40 and let us
know the results?
Many Thanks, 73
Allard PE1NWL
On Sun, July 1, 2018 15:59, Raj vu2zap wrote:
Correction 500KHz span!
At 01-07-18, you wrote:
Akira,
I just put my uBitxr4 on the spectrum analyzer and found nothing +-250
Khz. That is 500 Khz BW.
I think your measurements are being affected by switch mode power supply
in one of the items.
Raj
At 25-06-18, you wrote:
Hi!
I built Bitx40 about 2 weeks ago.
I measured the spurious of Bitx40 by using the spectrum analyzer.
The level of spurious of harmonics were under 50db. So this is fine.
But the spurious at 75KHz was observed.
The spurious might be the multiple of 25KHz.
It would be much appreciated if you could advise me the cause and
solution of this spurious of Bitx40.
In Japan, we must prove to the authority that the spurious of the
transceiver meets the criteria to obtain the certification of the
transceiver from the authority.
So if i could not resolve this spurious, I will not be able to use
Bitx40 in Japan.
Thanks in advance,
Akira
JJ1EPE
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Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Thanks Allard, goofed there. Will re-hookup the bitx40 later today and see.
toggle quoted message
Show quoted text
At 02-07-18, you wrote: Raj,
thanks for testing, but the issue that Akira san reported, is with BitX40,
not ubitx.
If possible, could you please repeat the same check with BitX40 and let us
know the results?
Many Thanks, 73
Allard PE1NWL
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Re: BITX QSO Afternoon/Evening, Sunday, July 1, 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
I didn't try tonight because I have the uBiTX in pieces waiting to get stuffed into a new box??
Dan, W2DLC?
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Really? Why do you say that? I find the OOP benefits to be well worth the effort to use them, especially encapsulation.
Jack, W8TEE
On Sunday, July 1, 2018, 10:59:38 PM EDT, AA9GG <paul.aa9gg@...> wrote:
C++ and micro-controllers do not really play well together.? That is why I use strictly ANSI C.
On Sat, Jun 30, 2018 at 2:11 PM, ajparent1/KB1GMX <kb1gmx@...> wrote: I take them seriously as it impacts future upgrades of the compiler which may
not accept it at all.? That and its a basic fix.
I'm an old Pascal user and wild type changes were not permitted.??
Also old assembler writer where you can do terrible things and
maybe survive.... ouch!
Allison
-- Paul Mateer, AA9GG
Elan Engineering Corp.
NAQCC 3123, SKCC 4628
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C++ and micro-controllers do not really play well together.? That is why I use strictly ANSI C.
On Sat, Jun 30, 2018 at 2:11 PM, ajparent1/KB1GMX <kb1gmx@...> wrote: I take them seriously as it impacts future upgrades of the compiler which may
not accept it at all.? That and its a basic fix.
I'm an old Pascal user and wild type changes were not permitted.??
Also old assembler writer where you can do terrible things and
maybe survive.... ouch!
Allison
-- Paul Mateer, AA9GG
Elan Engineering Corp.
NAQCC 3123, SKCC 4628
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Re: Running on a Jump Box
The unit is going to draw (amperage wise) what it needs.? You should not limit it.? Now VOLTAGE is a different story, you will want to set that between 12 to 13.8Vdc.? As stated use RV1 to adjust the output power.
On Sat, Jun 30, 2018 at 9:43 PM, Gwen Patton <ardrhi@...> wrote: That's extremely interesting and informative, and completely contrary to what I'm trying to do. I like the answers about using the pot on the board to lower the output power. Excellent. I'll probably do that.
But my initial problem was that, with a particular battery pack, the rig overdrove my tuner, making it fail to tune. Thankfully non-catastrophically, (i.e., it didn't catch fire) but it still wouldn't tune, and indications were that the power was out of range at the top end.
I realize that most users of radios want to MAXIMIZE output power, and then level it across as many bands as possible, so they have lots of output power in all of the bands they want to use. But I don't want to increase the power. I want to control it. The battery's specs list it at 12v @ 5A. So it has plenty of power and shouldn't limit the transmitter. But that's not my issue. The issue is that with that battery supply, there's TOO MUCH OUTPUT. If I run it from a bench supply, it doesn't do this. If I power the bench supply from the battery, it doesn't do this. I'm charging a battery bank I have with a 12vdc output jack, with a limit of 3A, that I'm going to test to see what IT does.
But I don't WANT to maximize RF out. I want to keep it within the limits of my tuner. I will try not setting a limit on the amperage and just try lowering the voltage, and see what that does, if limiting the amperage causes Bad Things.
Am I not being clear as to my goal in this instance? I'm trying to assemble a portable setup to take into the field for battery operation, but everything needs to play nicely with everything else, and the battery I was trying wouldn't play well with the tuner. I'm also testing to see if the problem might have been with the antenna or with the tuner, by testing different antennas and different tuners, to see if the problem actually exists with the BATTERY and not something else. If I can do it with a different battery pack that doesn't overwhelm the rig, PERFECT. But if that's going to cause bad harmonics or spurs or splattery signal, then that's not so perfect. I want to find the actual CAUSE of the difficulty, not just slap a band-aid on it or treat symptoms, but so far the assumptions I keep hearing are that I'm trying to maximize output, which is not the case. If I wanted to maximize output, I'd be building different sorts of radios, not QRP rigs.
-- Paul Mateer, AA9GG
Elan Engineering Corp.
NAQCC 3123, SKCC 4628
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Re: TX frequency? of uBitx at CWL and CWU mode
#ubitxcw
Sorry if I'm missing something but is there a "user manual" for the Memory Manager? I've never used it before...
Thanks
On Sun, Jul 1, 2018 at 9:04 PM, Ian Lee <kd8cec@...> wrote: Michael
I agree with you opinion, yes?There is not enough explanation for them :) I liked it the first time I implemented this feature.?
So I adopted it as a basic specification. That is, if no setting is made, 'TX' frequency is displayed unconditionally.
However, it is inconvenient for users who are familiar with the existing method.
So I decided to let the user choose by uBITX Manager.
Ian KD8CEC
--
Best 73
KD8CEC / Ph.D ian lee
kd8cec@...
(my blog)
-- 73 de Glenn VE3JAU
Thunder Bay, Ontario
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Re: BITX QSO Afternoon/Evening, Sunday, July 1, 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
Listened on 7.277 for a while, and
called CQ several times tonight around 7:30 and 10 PM EST. Didn't
hear anyone.
WB2VXW
On 7/1/2018 8:24 PM, Glenn Anderson wrote:
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Show quoted text
I'm just using my test leads for my multimeter (I'm at
work) as an antenna... If you guys are having this much
trouble it's no wonder I can't hear anything... HIHI
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Re: Questions regarding BitX40 build
Craig VE6TBW,
Question 1: that's what I did. Might want to search for older discussions on wiring up a diode between the socket and fuse holder to blow the fuse if power is ever hooked up wrong.
Personal note: It would have been easier to put in the VK3YE DDS noise filter if I planned it in first.
Question 2: I tried rotating mine in the first time. Made the mistake of pulling on the pot shaft and broke it, so I had to take it back out.
Question 3: My case came with 12 screws of the same type. M3 with a flat head with a rise in the center where a Phillips/Cross-head screwdriver goes. I used 4 to mount the Bitx40 board to the case without the standoffs. I stacked the Raduino together with all 8 standoffs, 2 in each corner. Nuts behind the Raduino. After everything else was installed on the front panel I was able to mount the Raduino through the clear bezel using some of the longer M3 case screws. (Might want to take the protective plastic off the LCD before to limit reflections and blurriness later)?
Question 4: There was a few discussions on what should be the standard for wiring up one of the mic TRS. Tip=Mic, Ring=PTT, and Sleeve=Ground. Or Tip=PTT, Ring=Mic, and Sleeve=Ground. Black wires from the Bitx40 headers are ground for my description.
I found some of the electret PC mics I had on hand would work as is with mic, PTT, GND so I standardized on that.
All in all, I like my Maroon Universal II case. I use a log pot on the upper Mic mount for RF gain. If I didn't love the RF gain so much, I'd have put a momentary button for amunters Function button.
The other hole I want is one to bolt the IRF510 to the back. Still needs an Isolation kit since the tab is PA_PWR voltage+. That would let the final amp use the case as a heatsink. One of these days I'll take it to a drill press and add 3 holes.
73 de Jacob AG7CT
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Re: RFI from uBitx TX after AGC and other mods installed
John, As of now it is just a leaded part that I
scabbed/tacked?on to the board.? It even has long legs. I was so
elated to have gotten rid of the audio and sometimes oscillations that I have
not gone back and finalized the issue.? Will probably just use the cap
that's on it now with short legs. Like I mentioned I will be using the JackAl
mod (Jack Purdum W8TEE)?when it becomes available so this AGC?mod will
be coming out. Used?it all evening on FT8 and a?QSO without a hint of
a problem. Hope?it takes care of your issues. Again my board was not the
Kee's board but one I made using Don's original drawing and plans
(SMD)?before the Kee's kit was available.?I have been in conversation
with Don and when he puts the cap in he still?gets squeals, but did finally
here the audio in?a?headset above 11 watts out,?so who knows. He
said he was?going to investigate further tomorrow.? Mine sounded like
RF getting into the audio as it was not real clear but kind of fuzzy and then
would sometimes go into ocillations or squals at higher RF
peaks.
Rick
KN4AIE?
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Show quoted text
Rick, Did you use a leaded part or SMT for the .01
cap? John KC9OJV
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Re: RFI from uBitx TX after AGC and other mods installed
Another data point...
I put a .01uf cap across the audio input the the AGC board (the Don & Kees kit) and it seems to have pretty much removed the audio from the speaker on xmit. I think it's still there but it's much, much less, just barely audible even with the volume turned up higher than I would usually have it. I didn't have a surface mount part so I soldered the smallest cap I had across the pins on the bottom of the board. Seems to have done the trick with no apparent ill effects. Many thanks to all who contributed to solving this puzzle.
Mark AA7TA
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Questions regarding BitX40 build
Hello.
I'm currently building a BitX40 Ver 3 in a AmateurRadioKits.in Universal Case Blue 2 for Bitx40 case and I have a couple of questions.
I wasn't able to find any instructions for using the Universal Case Blue 2, are there any?? It looks fairly straight forward but there are a few things I don't get.
Question 1
I'm going to wire DC Power by connecting the positive pin of the DC power jack to the fuse holder, then the fuse holder to the provided power button, then I will connect the general board power, PA power and Raduino power between the power button and the ground side of the power jack.? Does this sound correct?
Question 2
The tuner pot that came with the Bitx40 fits in the mounting hole on the case, but the none of the volume pots included in the Bitx40 kit or the Case kit fit in the audio gain mounting hole.? Am I just supposed to force it in, or am I missing something?
Question 3
I don't really see how the raduino LCD is supposed to mount onto the case using the screws that were provided.??
Question 4
There isn't a mounting hole for the PTT switch, but there is one for the mic.? Do I run the PTT through the mic jack somehow, or do something else?
Any help would be appreciated
Craig, VE6TBW
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Re: TX frequency? of uBitx at CWL and CWU mode
#ubitxcw
Michael
I agree with you opinion, yes?There is not enough explanation for them :) I liked it the first time I implemented this feature.?
So I adopted it as a basic specification. That is, if no setting is made, 'TX' frequency is displayed unconditionally.
However, it is inconvenient for users who are familiar with the existing method.
So I decided to let the user choose by uBITX Manager.
Ian KD8CEC
Ian :
Thanks for the reply. I noticed that option in the uBITX Manager but I couldn't find any documentation on what I meant.
Now I know, so I will give it a try.? I am not sure that this will "fix" the issue in switching back and forth between CWU and CWL,
but I will recheck after I try with this option enabled.?
What I have observed is ?that the RX Frequency stays the same when you switch from CWU to CWL, but the TX frequency is changed, which should not
be the case.
Thanks for the clarification.
Cheers
Michael VE3WMB?
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
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Re: RFI from uBitx TX after AGC and other mods installed
Rick,
Did you use a leaded part or SMT for the .01 cap?
John
KC9OJV
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Raj vu2zap
AA9GG
MadRadioModder