Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Ian,
When transmitting, we probably just set the BFO such that our transmitted voice sounds OK and leave it be.
Most of us will use exactly that same IF-Shift (or PassBandTuning, same thing) for all of our receiving too.
There are several reasons we might want to shift the BFO frequency when receiving:?
1)? Receiving a signal with a naturally high pitched voice, we will recover more of the vocal sounds
if the BFO is further from the filter.? (Closer if it's a low pitched voice)
2)? There might be a carrier near our operating frequency, moving the BFO one way or the other?
might move the offending carrier down the skirt of the filter so it's less objectionable.
Perhaps this is what your friend meant by "shift the IF passband to remove the ambient noise"
3)? We might want to zero-beat an AM carrier (such as from WWV at 10.0mhz) when calibrating the rig.
In this case we want the BFO in the middle of the filter passband.
Whenever we shift the BFO while receiving a signal, we also want to shift the VFO
so that we remain tuned exactly to the suppressed carrier of the incoming signal.
The code I presented takes care of that, adjusting the value of pbt will move?
both the VFO and BFO.
Otherwise, I don't think it makes sense to shift anything around once the rig is calibrated.
The user should somehow find a best setting for f12c and f45c (the center frequency
of the passband for the 12mhz and 45mhz filters), perhaps by just adjusting them for best sound
while receiving.? Alternately, sweep the filters with a sweeperino or tracking spectrum analyzer to find
the middle of the passband.? Set these values once, and forget about it.??
?
Here's an easy and accurate way to calibrate the rig using the C code I provided today:
Set pbt=0, so the BFO is in the middle of the 12mhz passband and we can hear the carrier when tuned to an AM station.
Call do_tune(10000000) to tune in WWV at 10.0 mhz.
This could be any AM broadcast station of known frequency.
If calibration is way off, you may not even hear the station.
Then do this:
while (not-zero-beat)? {
? ? adjust the value of si5351x_vco using the encoder
? ? do_tune(10000000)
}
When zero-beat is achieved, save si5351bx_vco to EEPROM
so we can power up fully calibrated next time.
This procedure should fully calibrate clk0, clk1 and clk2, to within a fraction of a hz.
Primary source of errors will be temperature changes causing the 25mhz reference oscillator on the si5351 to drift.
Here's an old post describing this method of calibration:
? ??/g/BITX20/message/35235
?
Also this post regarding shortcomings in how the original uBitx calibration code works.
? ??/g/BITX20/message/37973
Jerry, KE7ER
On Sun, Mar 11, 2018 at 05:42 pm, Ian Lee wrote:
The friend told me to shift the IF passband to remove the ambient noise.
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Re: ubitx case mount question regarding micro USB connector raduino
A number of us have tucked one of these in the case:
Makes it easy to access the Nano without opening the case.
Jack, W8TEE
From: Tom Christian <tmchristian@...>
To: [email protected]
Sent: Sunday, March 11, 2018 6:19 PM
Subject: [BITX20] ubitx case mount question regarding micro USB connector raduino
I'm looking for ideas on what others are doing regarding mounting a micro USB connector to the ubitx case.? I'm finishing the case customization and would like to be able to connect the raduino USB to my laptop (or a raspberry pi) for CAT and digital communication.? It would also be used for upgrading the firmware and debugging with the IDE.? I would like to be able to do this without having to open the case.? I haven't seen this anywhere on the blog yet (but I may have missed it).? The panel mount USB micro connectors I've see so far are pretty long (over a foot in length).? I may have to cut s cable and recrimp for a solution.? I'm curious what others have done.? A picture of my case is in another post:? /g/BITX20/topic/14362664? Thanks for any help you could give. Tom AB7WT
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Re: uBITX Firmware CEC Version Added WSPR function, I am looking for a beta tester.
#ubitx
Philip.
Sorry to have kept you waiting so long.
I can now sit at my desk.?I had to drive all weekend. lol.
(The role of the father is difficult.?My 5-year-old daughter is too active.)
I'll upload it in a few hours.?I will also modify the slect BPF routine.
After uploading, I will send the mail again.
The implementation of the WSPR feature already has many sources.
I just implemented a way to send wspr by uBITX alone without computer or raspberry pi, without any modifications.
The biggest role for uBITX in sending WSPR without any device is testers. Thank you all the time.
Ian KD8CEC
Hello Ian.
Is the WSPR frequency calculator in uBITX manager working correctly. Or is the uBITX transmitting on the wrong side band ?.
I would like test the update when you have done it.
Philip G7JUR
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Jerry
Thanks??for good code sharing. If you apply your code, can apply USB and LSB together with the same settings.
Ian KD8CEC
OK, here's some C code that should correctly keep our signal of interest centered
in both the 45mhz and 12mhz crystal filters, avoiding Gerald's problem of USB
sounding different than LSB.? This was a thread about Gerald's problem, right?
The variable pbt stands for PassBandTuning, and allows the user to?
adjust how far from the 12mhz filter the BFO will be, as discussed in the last
dozen or so posts.??
######################################################
// Initialized to typical values, can be configured by the user
uint32_t? f45c? = 44995000;? ? ?// center of 45mhz filter
uint32_t? f12c? = 11998000;? ? ?// center of 12mhz filter
uint32_t? pbt? ?=? ? ?1500;? ? ?// bfo is 1500 hz below f12c
char? ? ? isUSB = 0;
?
// Compute these values:
uint32_t? bfo, clk1, vfo;
?
// ftune is the freq in hz we want the rig tuned to
void do_tune(uint32_t ftune) {
? bfo = f12c - pbt;
? if (isUSB)? {
? ? // For USB, ftune = vfo-(clk1-bfo)
? ? clk1 = f45c + f12c;
? ? vfo =? ftune + (clk1-bfo);
? } else {
? ? // For LSB, ftune = vfo-(clk1+bfo)
? ? clk1 = f45c - f12c;
? ? vfo =? ftune + (clk1+bfo);
? }
}
#######################################
Jerry, KE7ER
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Jerry and all
Now I sit at my desk and have seen many opinions.
I have not read all of them in too many emails, but I am so happy to have reached a good conclusion.
I do not know if it's too late, but I'll tell you when I first implement the 'IF-Shift' feature for uBITX.
As you may have guessed someone who viewed my source, the source for implementing Filter is not all of the sources I wrote above.?
(I am sorry if you confused this with this.)
I have a friend who has a lot of great ideas.?The friend told me to shift the IF passband to remove the ambient noise.
And when I saw the circuit, I had to decide.?
As you all know, uBITX has twice frequency mixing.
It is using CLK # 2 and CLK # 1.
CLK # 2 generates a reference frequency for passing the desired frequency through a filter composed of 45Mhz crystals.
CLK # 1 generates a reference frequency for passing a filter composed of 12Mhz crystals.
My simple idea is that the frequency control source created by jerry is very good and did not need to be modified much.
Of course, CLOCK0 also makes the code look like it passes through the filter as shown below.
I had to choose one of them to reduce ambient noise. and? decided to use a part made of 12Mhz crystals that look sharper. So I wrote the above code.?
si5351bx_setfreq(0, usbCarrier + (isIFShift ? ifShiftValue : 0)); <--?This code is in the stopTX, Init parts for rx start.
Yes, this is to shift the BFO.
I thought about configuring it in the following form.?In this case, we did not have to worry about CLK0 throughout the code.
? ? ? si5351bx_setfreq(2, SECOND_OSC_USB - usbCarrier + f? + (isIFShift ? ifShiftValue : 0)); ? ? ? si5351bx_setfreq(1, SECOND_OSC_USB + (isIFShift ? ifShiftValue : 0)
);
Or, I thought about processing options as below.
(The code may be incorrect. Please consider it as a pseudo-code that you wrote during the writing of the mail now.)
? ? ? si5351bx_setfreq(2, SECOND_OSC_USB - usbCarrier + f?
+ (isIF1Shift ? if1ShiftValue : 0)
+ (isIF2Shift ? if2ShiftValue : 0));
? ? ? si5351bx_setfreq(1, SECOND_OSC_USB +?(isIF1Shift ? if1ShiftValue : 0)?);
Code in other parts
si5351bx_setfreq(0, usbCarrier + (isIF2Shift ? if2ShiftValue : 0)); <--?This code is in the stopTX, Init parts for rx start.
I wanted to give the user a tip to get rid of ambient noise for a while.?It was a short coding and in fact many tests were not done.
By your opinion, this feature will be more advanced.
In addition.(The bottom part is my guess, so it may be wrong.
I was hesitant to write this because it was still an experiment.
) I think BFO Calibration is done by all users.?This is because uBITX can not be used if BFO calibration is not performed. However, there is no calibration for 45Mhz.?I thought maybe modifying the part that is constant might improve the reception ratio a little more.
After implementing IF-Shift, I made several measurements through the Vector Network Analyzer. And we are doing simulation.
If I continue to improve uBITX, I will share experimental results later.
Thanks to Jerry's code, I was able to easily implement the functions I think very easily.
Thank you for sharing this great code.
Ian KD8CEC
Jerry,
Diddling with the BFO to make it a clarifier is not good. I agree it is a bad idea today. It worked back in the 50's and 60's because there wasn't much of any other choice and the filters weren't as sharp as they are today. It's why on the old RME 4350 it was always recommended to reset the bfo dial to zero. If you didn't your transmitted frequency wouldn't necessarily jive with your received frequency. Of course back then, a 1kc resolution was considered good and most people had separate receivers and transmitters so it didn't matter as much.
If you want a true clarifier it should be done with the vfo frequency and the offset from the transmitted carrier frequency should be indicated somewhere on the display.
Based on the message Allard left earlier, he *did* implement a true PBT by adjusting the vfo and the bfo so the suppressed carrier frequency is not changed but the relationship to the SSB filter changes. Again, it just goes to show how advanced this little rig actually is!
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
|
Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
OK, here's some C code that should correctly keep our signal of interest centered in both the 45mhz and 12mhz crystal filters, avoiding Gerald's problem of USB sounding different than LSB.? This was a thread about Gerald's problem, right? The variable pbt stands for PassBandTuning, and allows the user to? adjust how far from the 12mhz filter the BFO will be, as discussed in the last dozen or so posts.?? ######################################################
// Initialized to typical values, can be configured by the user
uint32_t? f45c? = 44995000;? ? ?// center of 45mhz filter
uint32_t? f12c? = 11998000;? ? ?// center of 12mhz filter
uint32_t? pbt? ?=? ? ?1500;? ? ?// bfo is 1500 hz below f12c
char? ? ? isUSB = 0;
?
// Compute these values:
uint32_t? bfo, clk1, vfo;
?
// ftune is the freq in hz we want the rig tuned to
void do_tune(uint32_t ftune) {
? bfo = f12c - pbt;
? if (isUSB)? {
? ? // For USB, ftune = vfo-(clk1-bfo)
? ? clk1 = f45c + f12c;
? ? vfo =? ftune + (clk1-bfo);
? } else {
? ? // For LSB, ftune = vfo-(clk1+bfo)
? ? clk1 = f45c - f12c;
? ? vfo =? ftune + (clk1+bfo);
? }
}
#######################################
Jerry, KE7ER
|
Re: BITX QSO Afternoon/Night, Sunday, March 11, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Been calling off and on
all day. I would think that my ubitx wasn't working but
I worked a station in Oklahoma with a 59 so its not me. I'm just
not hearing any
of the bitx stations. I will keep trying. Also forget the 7177
not a good frequency
due to stations too strong on 7175. I will from now on be
checking 7178.
Ed W0OIC
On 3/11/2018 6:56 PM, Tom VE3THR wrote:
toggle quoted message
Show quoted text
Thanks Richie...that
was probably you I heard earlier right in my noise floor. Looking
forward to radio contact. Too many chores today to spend a lot of
time on radio - i know - poor planning on my part.?
FYI I listen on 7.277 most days and night if in the shack or shop
- always looking for qso's other than just sundays. Give a call
and let's make some NOISE !
|
Re: BITX QSO Afternoon/Night, Sunday, March 11, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
KC1AT et all. I think the band was extremely poor today/tonight. Only heard W0OIC calling tonight. The afternoon slot 3PM (really 4PM) stands a better chance until propagation picks up. Crap shoot no less! Maybe Willy W1LY will get on later and light up the skies.
73 Tom
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Hard core uBITx developers
?BITx developers have been hard at work, and I have written a bit of a round up off the hard core developers, and given a bit of a glimpse at what some of them are hatching in their workshops right now:
I am unlikely to have captured everybody that is at work on ?BITx mods, so if you are working on something let me know (info@...) or let everybody know by writing a post to this list!
I have also been working on the "synthesis" articles (all those menu items before you get to the news stories).?? There is more work to do on these, but most now have some basic content.?? Any comments and criticisms will be gladly received, as I would like these to be really helpful to those constructors starting out, and to those wanting a new mod challenge.
73
Mike ZL1AXG ubitx.net
--
Mike Woods
mhwoods@...
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Re: BITX QSO Afternoon/Night, Sunday, March 11, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Heard N6ORS but guess he couldn't hear me I think he was running 60W. He was chatting with Mike NX2U but I couldn't hear him...Otherwise quiet.
Think I got to get on in the 3PM slot...seems like I had a lot better luck in that time frame.
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Re: RD16HHF1 power curve flattening...some
Also,? RV1 Drive level has no effect on the feedback issues, happens just the same at 5W as at 15W...
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Re: BITX QSO Afternoon/Night, Sunday, March 11, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Thanks Richie...that was probably you I heard earlier right in my noise floor. Looking forward to radio contact. Too many chores today to spend a lot of time on radio - i know - poor planning on my part.?
FYI I listen on 7.277 most days and night if in the shack or shop - always looking for qso's other than just sundays. Give a call and let's make some NOISE !
|
Re: RD16HHF1 power curve flattening...some
Well, i have dont my mods and powered up. Results are mixed:
Here are the mods.
RD16 replace IRF510.
New output transformer 1:4 BN43-3321 with a 330pf cap on input.
feed back resistors. from 22ohm to 1 K ohm
piggy backed R87 and R88 with 220pf capacitor.
RV1 full drive.
So results.
80M - 20W + ( blew my 2 Amp fuse)
40M - 18W - Seems stable.
30M - 17W BUT I get BAD feedback/ oscillation by just going PPT with no voice. The watt meter goes up to 18W!
20M - 15W? -? Same feedback issue
15M -? Same feedback issue.
10M -? Same feedback issue.
I have been thinking ans looking at other RD16 schematics, in alot of cases they dont use the feedback on the finals?
Also could this issue be cuase in the driver stage?
THanks guys, I am in over my head here....
73
10M - Same feedback issue
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Re: BITX QSO Afternoon/Night, Sunday, March 11, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Was able to speak briefly with NX2U and then the band dropped out. Made first contact with my ICOM-7300 and then set up the uBITX.? Had a few words with him and then nothing.? Using an LDG QRP autotuner and a Timewave DSP9+ with the uBITX
--Neil, W2NDG
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Re: RD16HHF1 power curve flattening...some
Thanks for your information!
Hi John
Totally out of the box uBITX, (ie no mods)? I checked power out in CW mode
120118
Checked using CW key at 12.5v dc in. VR1 at ~60% anti-clockwise. (factory setting)
¡¤?????
¡¤???????? 80M = 12w
¡¤???????? 40M = 8.5W
¡¤???????? 20M = 4.8W
¡¤???????? 10M = 1.2W
Turning up VR1 to full rotation.
80M = 15w
40M = 12w
20M = 7.8w
10M = 2w
glenn
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Re: BITX QSO Afternoon/Night, Sunday, March 11, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
7:45 local time in EST - where is everybody hanging out? Not hearing anything except my neighbours washing machine and I don't speak "machine language" .
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Re: BITX QSO Afternoon/Night, Sunday, March 11, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Hearing NX2U off an on. Called, but no answer!
--
John - WA2FZW
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Re: ubitx case mount question regarding micro USB connector raduino
On my latest BITX40 I snuggled the display up next to the edge of the case close enough to enable easy access through the side of the cabinet with just a minuscule aperture. Hardly visible. On the uBITX I used a very short adapter cable (about a foot long) and brought it to the back panel. A short extension cable then connects it to the computer for re-flashing the Nano. It works well and I can avoid opening the case every time that I feel like changing the software (which is frequent). Two caveats: Keep the cables short, and use good cables. Otherwise it is wonderfully advantageous. -Don
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Re: BITX QSO Afternoon/Night, Sunday, March 11, 3PM/7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Was able to work Nx2U and one other operator. Hearing carrier from 7.25mhz.? 7.29mhz is better
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Jerry,
Diddling with the BFO to make it a clarifier is not good. I agree it is a bad idea today. It worked back in the 50's and 60's because there wasn't much of any other choice and the filters weren't as sharp as they are today. It's why on the old RME 4350 it was always recommended to reset the bfo dial to zero. If you didn't your transmitted frequency wouldn't necessarily jive with your received frequency. Of course back then, a 1kc resolution was considered good and most people had separate receivers and transmitters so it didn't matter as much.
If you want a true clarifier it should be done with the vfo frequency and the offset from the transmitted carrier frequency should be indicated somewhere on the display.
Based on the message Allard left earlier, he *did* implement a true PBT by adjusting the vfo and the bfo so the suppressed carrier frequency is not changed but the relationship to the SSB filter changes. Again, it just goes to show how advanced this little rig actually is!
|
Nick VK4PP
Neil Goldstein
Don, ND6T
_Dave_ AD0B