Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Whoops, that did not get stated in post 44182.? My apologies.? (Was in the earlier draft mentioned in post 44228) Has been discussed in the forum here several times, though that was a few thousand posts ago.
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On Sun, Mar 11, 2018 at 09:40 am, Jerry Gaffke wrote:
No, the BFO is always below the 12mhz filter passband, if above then harmonics beat with an oscillator on the Nano. As stated in post 44182.
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Hi Tim,
yes, PBT and "clarifier" are indeed two different things.
When I implemented this functionality in the Raduino v2 sketch for BitX40, I initially called it "clarifier", however later I realised this was not the correct term. I later renamed it to Pass Band Tuning as I believe that is more appropriate.
Whatever you call it, technically it allows the operator to shift the BFO frequency during RX, and at the same time the VFO frequency is shifted by the same amount (so that the relationship of the BFO to the suppressed carrier is not affected).
If you still have a BitX40, try it out this simple mod and you will be amazed about this feature.
73 Allard PE1NWL
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On Sun, March 11, 2018 16:11, Tim Gorman wrote: Allard,
I don't think I agree with you. PBT and "clariier" are two different things.
A "clarifer" or incremental tuning control is only useful for tuning an off-frequency signal. The BFO must be at the suppressed carrier frequency for proper detection of a SSB signal. If you deviate from that frequency then the detected audio becomes distorted, the old "donald duck" sound spoken of by the old-timers. One of my first ham-band receivers was an old RME-4350, 1950's vintage. It had a "BFO" control which was really useful on SSB because in a round-table not all transmitters could be set to the exact same frequency - resolution of 1kc was pretty good! The BFO could be used to tune everyone in properly, in essence it was what is today called an "receiver incremental tuning" control.
Passband tuning (or IF Shift) does not impact the relationship of the BFO to the suppressed carrier at all. You could do the IF Shift by changing CLK1 in order to shift where the signal impacts the 12Mhz passband of the SSB filter but CLK0 would still have to maintain the same relationship to CLK2 in order to demodulate the signal properly.
tim ab0wr
On Sun, 11 Mar 2018 01:09:24 +0100 "Allard PE1NWL" <pe1nwl@...> wrote:
Jerry,
I believe it works in a similar way as the PBT (or "clarifier") function in the Raduino v2 software for Bitx40.
It allows the user to slightly shift the BFO frequency from the frontpanel (only during RX of course). It's not IF shift in its true sense, but the behaviour is quite similar. I have the impression that not many BitX40 builders actually installed this mod, which has always surprised me as I personally find it a very useful feature.
73 Allard PE1NWL
On Sun, March 11, 2018 00:52, Jerry Gaffke via Groups.Io wrote:
OK, so IF-Shift is just a BFO offset (relative to the crystal filter passband)???? that is for receive only, the transmit BFO offset generally stays put. Makes sense.
I went off into the weeds there because Gerald's original query stated that
????In LSB I can adjust the received sound with the IF-Shift with a very pleasing effect, but this does not work the same with USB. Sounded like there was something more going on. But could be just that the code didn't quite handle the USB case correctly.
Yes, eventually I'll move on to try some of the newer software. But for now have my hands full with other projects.
Jerry????????
On Sat, Mar 10, 2018 at 02:49 pm, Mike Woods wrote:
Most commercial rigs have an IF Shift or Passband Tuning (PBT) control.???? This control can help with removal of QRM on receive ( e.g.by ( ) eliminating a strong carrier or another station on the edge of the passband by shifting the passband up or down by a few 100 Hz. It can also compensate for a poorly adjusted frequency response on a signal that is being received (too bassy or too trebly).?? ???? Ian????????s software implements just such a control.???? It
functions in
a similar manner to the BFO calibration routine, in fact, but unlike the calibration function, it should only operate on RX. This was the bug - it didn????????t turn off on TX.???? I checked on my uBITx and found the same problem here. ???? If you haven????????t tried the KD8CEC firmware you should.???? It has a
number of other worthwhile software features! ????
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Re: ubitx mount question regarding lcd display and bezel
Here is a solution that I used.. QRP- labs.com /enclosures front panel . There are unmarked panels that the display fits in,with four holes around the display that the jacks fit into nicely . I'm not sure how long shipping will take from Japan,but I bought a few for later projects . It is nice to have extra stuff sometimes. 73 Dennis
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Guys & Gals, I didn't want to leave anyone out. I just thought I should remind everyone that this is a forum for the BitX (all BitX's). It is made up with thousands of radio amateurs who want to expand and enjoy their hobby. I have been licensed for 64 years now. I am a Technician (not an Engineer). I fix things, build them, troubleshoot them, analyze them, I read schematics, what I don't do is design things! Farhan has done an excellent job with the BitX and has made many improvements to his designs. He has put out a quality product that thousands have enjoyed using. Basically the BitX is a great entry level transceiver that is affordable for all. It is not a perfect transceiver, but that is what this forum is for, to share modifications, improvements, and new ideas with each other. We do have outstanding Engineers on this forum. No matter what your background is, there is help for you on this forum. If it doesn't work, someone will help you troubleshoot and find the answer. There is no warranty on the BitX. It is being offered that way to keep the costs down. I have one of the first uBitX's shipped. I put it together in a small chassis, I found a few mistakes and I fixed them. My output power with 12.6 volts applied is about 8 watts on 40 meteres. My first contact was 1500 miles away with a S9 report. I'm almost afraid to add any mods to it since it works sooo good. For beginners, when you get your uBitX, I have a few suggestions, First, follow the instructions, do not try to read the schematic, use the pictures in the instructions for placement of the colored wires. For the 3.5 mm speaker jack, do not jumper the tip to the ring, this will prevent shorting audio out when a mono plug is inserted. Last suggestion - It is a QRP transceiver, don't try to get more power out of it! If you need more power, use an external amplifier, there is a file on this forum on how to do this. Most power supplies run up to 13.8 volts, don't go over that, I chose 12.6 volts and nothing gets hot and I can use digital. Lastly, respect everyone on this group, we are from all over the world and we are all friends in our hobby. Ed W0OIC
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Michael, would you provide a link to your kits?
Thanks, Roy WA0YMH
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On Mar 11, 2018 12:42 PM, "Michael Hagen" < motdog@...> wrote:
Here is the STL file
for my Bezel.? As most know, 3D printing is hit and miss.
My kit includes the
Bezel, Metric Flat head screws, sheet metal screws, ABS
standoff, and ABS 1/8" spacers for
using original metal
standoffs or all Plastic.? It was for orginal BitX on a 1/16"
al. panel, uBit users may have to improvise.
Have at it, it takes
about 1 1/2 hr. to print and I get to throw out 1 out of 3
prints because of warping (pulling up at the ends).
73's Mike
On 3/11/2018 9:15 AM, Lawrence
Macionski via Groups.Io wrote:
WA6ISP has them for
sale in his catalog list -$4.00
Larry- W8LM
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
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Here is the STL file
for my Bezel.? As most know, 3D printing is hit and miss.
My kit includes the
Bezel, Metric Flat head screws, sheet metal screws, ABS
standoff, and ABS 1/8" spacers for
using original metal
standoffs or all Plastic.? It was for orginal BitX on a 1/16"
al. panel, uBit users may have to improvise.
Have at it, it takes
about 1 1/2 hr. to print and I get to throw out 1 out of 3
prints because of warping (pulling up at the ends).
73's Mike
On 3/11/2018 9:15 AM, Lawrence
Macionski via Groups.Io wrote:
WA6ISP has them for
sale in his catalog list -$4.00
Larry- W8LM
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
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Re: OT: RE: out of specification operation with Si4721 for use on 4 Meters
#parts
Question here, what basically would it take to make these into a 9600baud? or better digital transceiver?
On Mar 11, 2018, at 12:12, Lawrence Macionski via Groups.Io < am_fm_radio@...> wrote:
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I've built 2 "Handie-Talkie" type devices.Using DOJORI
DRA818V VHF Band Voice Transceiver Module V1.21- I have found them on Ebay- in single lot quantities for $11. You program them with a USB to TTL (UART) serial dongle. You can program them with CTCSS and DPL, both receive and Xmit. 1 watt output. I've
run them at 3.0V (2AA's) and they tune 134-174 Mhz. There is also a UHF version-
DRA818U. They will remember (powered off) 1TX freq, 1RX freq. RX or TX Tone type, RX or TX Tone Frequency, It has 8 squelch levels and 8 volume levels.. TX out is 500/1000mW
It basically looks like a 1/2 stick of gum in aluminum foil wrap. Down side.. simple 3-4 component bandpass filter needed on XMIT.. 2nd harmonic reduction is needed.
-Larry W8LM
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Re: The issues of the TDA2822
Have been reports here of clone chips that inexplicably blow if fed more than 7vdc. Appears to be several clone brands that sell parts made from factory floor sweepings, other projects have been caught up in this problem as well. Read the instructions as many times as you want, a WX might still blow.
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On Sun, Mar 11, 2018 at 10:15 am, David Lacey wrote:
When you read the myriad of posts on the subject of the exploding audio chip it is easy to see a lot of the problem lies with the over-enthusiastic owner..... not reading instructions, not understanding exactly what they are doing and the resulting problems.
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Tim,
I think I now understand the offset you were referring to. That's a good point, and this might be key to Gerald's problem of hearing different audio on USB than LSB.
The answer, I think, is to keep the 2000 hz slice of the signal we are receiving centered on the passband of the 45mhz filter. As described in post 44182, the original uBitx code moves that slice by 4khz when we switch from LSB to USB, rather significant given that in some versions the 45mhz crystal filter can have a 3db passband of +/- 3.75khz.? ?Post 44182 proposes new values for clk1 that should fix the issue.
I first wrote a much longer version of post 44182, spelling out exactly where the carriers and sidebands wind up at each stage in the rig for both LSB and USB cases, and how and when and why the sidebands get inverted by the two mixers. If 44182 gets vetted here in the forum, I'll post that longer version of what I think is going on.
And someday I should dig out my uBitx and see if my solution works. Maybe even get it on the air.? ?;-)
Jerry, KE7ER
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On Sun, Mar 11, 2018 at 09:40 am, Jerry Gaffke wrote:
You state: >? Does the ubitx software maintain a CLK0(USB) and a different CLK0(LSB)?
No, the BFO is always below the 12mhz filter passband, if above then harmonics beat with an oscillator on the Nano. As stated in post 44182.
>? If not then changing the BFO (CLK0) by itself will result in an >? asymmetric USB and LSB since the actual suppressed carrier freq now has >? an offset.
I guess this agrees with what I was saying in post 44182, though it's not terribly clear exactly what asymmetry or exactly what offset you are referring to. There's a bunch of contenders here. Yes, changing only the BFO when trying to listen to a signal is generally a bad idea.
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Re: Dirt cheap uBitx case
#ubitx
Nice case. Not sure you would want to open the discussion to a "case" discussion in General so I possibly apologize in advance, but the Brazilians are making some of the nicest cases I've seen. For an example, check this one out?  ? ? ? ? And this one?
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Re: The issues of the TDA2822
I don`t think you were forceful at all, simply said what you
thought.
When you read the myriad of posts on the subject of the exploding
audio chip
it is easy to see a lot of the problem lies with the
over-enthusiastic owner.....
not reading instructions, not understanding exactly what they are
doing and the
resulting problems.
This is NOT a dig at those who have had problems....simply step back
and think first !
Ok we have all made mistakes (sometimes costly ones), you just have
to put it down to
experience, suck it up, replace the broken part and start again.
That is what this hobby
ia all about, you start at the bottom and work your way up gaining
knowledge and importantly
experience along the way.
As for Ashar having to take the flak...I feel sorry for the
guy....he is under a lot of pressure
and.......he is doing it all for US !
Dave
On 11/03/2018 17:00, Gordon Gibby
wrote:
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Well, I might¡¯ve been a bit too forceful, but I wanted people to
understand that creating a product out of thin air, manufacturing
and shipping it all over the world is quite an undertaking. ? If
all he has struggled with are a few issues like these, the man is
a magician.
I learned more in the first week on this forum than I had
learned in years else where.
I¡¯ve used the bit extra to make multiple multiple contacts
even though I literally turn it on, used it to teach ham after
ham Techniques because I can point to the actual components
doing the jobs.
It¡¯s in the price range of newcomers to our happy who are
teenagers.
My first rig was a Heathkit HW16, which I earned by
vacuuming, soldered together, and wasn¡¯t able to get it working
for almost 6 months.
I should¡¯ve been so lucky to have a blown up component to
tell me where the problem was!
On Mar 11, 2018, at 12:02, Jerry Gaffke via Groups.Io < jgaffke@...>
wrote:
From Farhan's post:?
>? just about 100 out of 4000 boards have had this
problem.
>? and about less than 20 of them have reported the blow
out."
So 100 boards got the WX part.
They all got turned on at HFSignals.in final test, very
very few of the WX parts blew there.
It's only after they get out into the field and have a bit
of operating time on them,
or perhaps see supply voltages of 14v or so, or have the
speaker jack momentarily shorted,
that we see the 20 failures.? ?
HFSignals has a 2 month backlog on this product, and is
scrambling to keep kits going out.
Lots of new electronics gear from established
manufacturers will have these teething issues.?
Most of us have a spare LM386 or LM7805 from some older
project we could patch in,
and if not they are easy enough to get.
What solution do you propose that's appropriate for a $109
kit
shipped from halfway around the world??
Jerry, KE7ER
On Sun, Mar 11, 2018 at 08:16 am, Christopher Miller
wrote:
With all due respect sir, I eventually would
like to purchase this kit as soon as I finish my
disability claim in a month or so. This seems like a
pretty serious issue. I am sure you didn't plan on parts
failing but simply pointing out is only a percentage of
your total production run isn't a solution.?
?
Overall from all the posts I read this kit is
great. However I suspect you realized when shipping
the boards with bad audio amps that it was an issue.
If the original part was less than a dollar, you can
easily raise the price by .50$ to 1$ us to cover the
cost of putting a good part in.?
?
Thats just my .02$
?
kf4ftr
Chris?
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Re: OT: RE: out of specification operation with Si4721 for use on 4 Meters
#parts
very cool Larry, even if the Si4721 can't be used in a HAM band it can still be used as a "Handie Talkie" in the FM broadcast band within the limitations of the Part 15 rules here in the US.?
-Justin N2TOH?
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Re: The issues of the TDA2822
Well, I might¡¯ve been a bit too forceful, but I wanted people to understand that creating a product out of thin air, manufacturing and shipping it all over the world is quite an undertaking. ? If all he has struggled with are a few issues like these, the man
is a magician.
I learned more in the first week on this forum than I had learned in years else where.
I¡¯ve used the bit extra to make multiple multiple contacts even though I literally turn it on, used it to teach ham after ham Techniques because I can point to the actual components doing the jobs.
It¡¯s in the price range of newcomers to our happy who are teenagers.
My first rig was a Heathkit HW16, which I earned by vacuuming, soldered together, and wasn¡¯t able to get it working for almost 6 months.
I should¡¯ve been so lucky to have a blown up component to tell me where the problem was!
On Mar 11, 2018, at 12:02, Jerry Gaffke via Groups.Io < jgaffke@...> wrote:
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From Farhan's post:?
>? just about 100 out of 4000 boards have had this problem.
>? and about less than 20 of them have reported the blow out."
So 100 boards got the WX part.
They all got turned on at HFSignals.in final test, very very few of the WX parts blew there.
It's only after they get out into the field and have a bit of operating time on them,
or perhaps see supply voltages of 14v or so, or have the speaker jack momentarily shorted,
that we see the 20 failures.? ?
HFSignals has a 2 month backlog on this product, and is scrambling to keep kits going out.
Lots of new electronics gear from established manufacturers will have these teething issues.?
Most of us have a spare LM386 or LM7805 from some older project we could patch in,
and if not they are easy enough to get.
What solution do you propose that's appropriate for a $109 kit
shipped from halfway around the world??
Jerry, KE7ER
On Sun, Mar 11, 2018 at 08:16 am, Christopher Miller wrote:
With all due respect sir, I eventually would like to purchase this kit as soon as I finish my disability claim in a month or so. This seems like a pretty serious issue. I am sure you didn't plan on parts failing but simply pointing out is only a
percentage of your total production run isn't a solution.?
?
Overall from all the posts I read this kit is great. However I suspect you realized when shipping the boards with bad audio amps that it was an issue. If the original part was less than a dollar, you can easily raise the price by .50$ to 1$ us to cover
the cost of putting a good part in.?
?
Thats just my .02$
?
kf4ftr
Chris?
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Tim,
Good, looks like you now agree with my ost 44182 that moving the VFO + BFO is a better solution than?moving clk1 + BFO.
As I stated in post 44182, the original uBitx code only moves the BFO when doing a BFO Adjust, and you agree that this is not ideal.
Is there anything in post 44182 (as slightly amended in 44196 and 44200) that you disagree with?
You state: >? Does the ubitx software maintain a CLK0(USB) and a different CLK0(LSB)?
No, the BFO is always below the 12mhz filter passband, if above then harmonics beat with an oscillator on the Nano. As stated in post 44182.
>? If not then changing the BFO (CLK0) by itself will result in an >? asymmetric USB and LSB since the actual suppressed carrier freq now has >? an offset.
I guess this agrees with what I was saying in post 44182, though it's not terribly clear exactly what asymmetry or exactly what offset you are referring to. There's a bunch of contenders here. Yes, changing only the BFO when trying to listen to a signal is generally a bad idea.
Jerry, KE7ER
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On Sun, Mar 11, 2018 at 09:06 am, Tim Gorman wrote:
Jerry,
This is a very complicated subject. The BFO, i.e. CLK0 *has* to be at the suppressed carrier frequency in order to properly demodulate the signal.
In order to do PBT you would have to shift three variables, CLK2, CLK0, and the indicated frequency.
Conditions: 10Mhz suppressed carrier CLK2 at 35Mhz to shift signal to 45Mhz CLK1 at 33Mzh to shift signal to 12Mhz CLK0 at 12Mhz to demodulate the signal Freq Indicator at 10Mhz
Assume we want to shift the signal 500hz to get rid of an interfering carrier.
Conditions: 10Mhz suppressed carrier CLK2 at 35,000,500hz to shift signal to 45,000,500hz CLK1 at 33Mhz to shift signal to 12,000,500hz CLK0 at 12,000,500hz to properly demodulate the signal Freq Indicator at 10Mhz This would move the interfering carrier up and out of the passband.
I agree this would implement PBT or IF Shift.
This is not, however, what was being described. Moving CLK0 is truly incremental tuning without the frequency indicator being changed. When you move the BFO without also moving CLK2 you are changing what frequency is considered as the suppressed carrier frequency. It will change the relationship of all demodulated audio. If you are listening to a CW carrier the pitch of the CW carrier will change as you change the BFO (i.e. CLK0) by itself. This is exactly what is needed to tune in a signal that is slightly off frequency.
Let's consider what happens if you change CLK1 and CLK0.
Conditions: (same as original, 10Mhz Suppressed cxr,CLK2 =35Mhz, CLK1=33Mhz, CLK0=12Mhz)
New Conditions: (move passband 500hz) 10Mhz suppressed carrier CLK2=35Mhz to shift signal to 45Mhz CLK1=32,999,500hz to shift signal to 12,000,500hz CLK0=12,000,500hz to properly demodulate the signal Frequency Indicator at 10Mhz
Same result. You can obtain PBT by changing 2 variables. You can't do it by changing just one.
Does the ubitx software maintain a CLK0(USB) and a different CLK0(LSB)? If not then changing the BFO (CLK0) by itself will result in an asymmetric USB and LSB since the actual suppressed carrier freq now has an offset.
This is what was being described.
tim ab0wr
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Re: The issues of the TDA2822
I agree with Gordon. I have gotten bad components from reputable suppliers such as Mouser and Digikey. It happens. It's annoying. But it's not Farhan's fault. Heck, I have even had component failure in my Yaesu FT-3000 on an *out-of-warranty* basis and they want a fortune to do out-of-warranty repair! At some point we may see enough bitx and ubitx radios in circulation that someone will open a repair business for them. But I'll bet you money it will likely cost so much that you could buy another kit instead! tim ab0wr On Sun, 11 Mar 2018 15:30:52 +0000 "Gordon Gibby" <ggibby@...> wrote: Oh for crying out loud!
Could you folks leave this fellow alone? He¡¯s manufacturing A quality piece of equipment for chicken feed, under difficult circumstances, when nobody else rose to do the job. He¡¯s run out of parts at least twice now when the worldwide demand for his product exceeded the worldwide supply of quality components!
He didn¡¯t ask component manufactures to make him inferior parts, he simply purchase when you could find on the open market.
Once he ships it, it¡¯s beyond the pale to ask him to find a broken ones and replace them! All he can do his estimate the incidence, and try to find better component manufacturers.
If any of you want gear that is warranteed, built in first world circumstances, tested, then go pick yourself up an Icon 718 for about $650 US.
If you¡¯re not willing to learn a bit, work a bit, fix a bit, understand a bit, then please get off this man¡¯s back. It¡¯s unfair what you¡¯re doing.
Gordon L Gibby On Mar 11, 2018, at 11:17, Christopher Miller <djmalak2k6@...<mailto:djmalak2k6@...>> wrote:
With all due respect sir, I eventually would like to purchase this kit as soon as I finish my disability claim in a month or so. This seems like a pretty serious issue. I am sure you didn't plan on parts failing but simply pointing out is only a percentage of your total production run isn't a solution.
Overall from all the posts I read this kit is great. However I suspect you realized when shipping the boards with bad audio amps that it was an issue. If the original part was less than a dollar, you can easily raise the price by .50$ to 1$ us to cover the cost of putting a good part in.
Thats just my .02$
kf4ftr Chris
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Well I'm used to you criticizing what I write as if you don't understand it.
Vince.
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On 03/11/2018 12:21 PM, Tim Gorman wrote: Wow! Testy, aren't we?
I know I said basically the same thing as you. I just explained it a little differently!
It was not meant to be a criticism of what you wrote!
tim ab0wr
On Sun, 11 Mar 2018 12:16:05 -0400 "Vince Vielhaber" <vev@...> wrote:
Did you even read what I wrote? If so, did you comprehend? You repeated the same thing I wrote.
Vince.
On 03/11/2018 10:37 AM, Tim Gorman wrote:
Vince,
If you are listening to a CW signal then moving the IF Shift doesn't change the tone of the CW signal at all. You are just moving the passband. That can change the sound of a SSB signal because you are removing some of the received audio along with the interfering signal. Just like cutting the highs or lows with a treble/bass tone control.
tim ab0wr
On Sat, 10 Mar 2018 21:07:17 -0500 "Vince Vielhaber" <vev@...> wrote:
IF Shift is supposed to shift the signal thru the passband without changing the frequency. So if you're listening to 3930 and there are signals on 3928 (it happens daily) at the same time, you can use the IF Shift to move the signals on 3928 out of the passband. If affects the sound of the desired signal like a tone control but that's a side effect of the action.
Vince.
On 03/10/2018 09:02 PM, Ronald Pfeiffer via Groups.Io wrote:
Yes I was confused a while back when Ian announced his IF shift. The code looked just like our RIT. Our RIT displays the freq on bottom line and the line above displays the plus/minus offset as you move the encoder.
rOn
------------------------------------------------------------------------ *From:* Tim Gorman <tgorman2@...> *To:* [email protected] *Sent:* Saturday, March 10, 2018 8:24 PM *Subject:* Re: [BITX20] #uBITX Firmware KD8CEC - IF-Shift etc.
I wonder if we need to define some terms here. Passband tuning and IF Shift typically move the *filter*, not the carrier. The carrier will remained tuned to the same frequency when adjusting this. For instance, if you use IF Shift when listening to a CW signal the tone of the CW signal should not change. You can move the filter bandwidth up or down to eliminate an interfering carrier that is close to the desired frequency.
What you are describing is more like an Incremental Tuning, e.g. RIT or XIT. When you move the BFO you move the carrier frequency, not the filter bandwidth.
Ideally the BFO would be set to replicate the suppressed carrier frequency. The filter then determines what is heard.
The ubitx uses a 12Mhz crystal filter. I don't know its bandwidth or what the actual absolute frequencies are. I haven't had a chance to run a spectrum analyzer against mine. Let's assume it has a 2400hz bandwidth and goes from 12,000,300hz to 12,002,700hz.
If you want to listen to a signal at 10Mhz then CLK2 should be tuned to 55Mhz to generate the 45Mhz signal the first IF needs.
CLK1 should then be set to generate a 12Mhz signal, i.e. 33Mhz. For an USB signal we should then see frequencies of 12Mhz to 12.003Mhz (or whatever the transmitted bandwidth is, e.g. 0-3000hz). You will then see frequencies of 12.0003Mhz to 12.0027Mhz out of the filter.
This is how an ideal receiver would work.
When you are talking about adjusting the BFO I assume you are talking about adjusting CLK1. If you adjust CLK1 to move the actual suppressed carrier frequency somewhere else in the filter bandwidth then your frequency indication is going to be off. What should be a 10Mhz signal is going to look like something else.
This will cause an asymmetric USB and LSB response and frequency indication.
If you want to change the BFO frequency on the fly then it should be understood as being an incremental tuning so you can remember what the base frequency should be.
Now each filter is probably going to have a different actual physical, absolute bandpass. The BFO will have to be adjusted to allow for this but the frequency indication needs to be adjusted as well to match. It should be a fixed reference, not a variable one.
Your transmitted frequency has to be offset from the CW-tone if it is to be zero beat with the received signal. If it isn't then you'll never be zero beat. I'm assuming that the CWL and CWU frequencies are indicating a frequency CW-tone away from the actual transmitting frequency. That may be because your receive BFO frequency isn't set to indicate actual carrier frequency.
I didn't mean for this to get so complicated but it isn't an easy subject.
tim ab0wr
On Sun, 11 Mar 2018 01:08:55 +0100 "ge_clipboard" <clipboard@... <mailto:clipboard@...>> wrote:
Hi All
Many thanks for all the response concerning the BFO adjustement and about using the IF-shift. I have been playing around with the BFO setting while monitoring myself on another transceiver but as I¡¯m not getting there where I really would like to, I returned to the factory settings. Leastening to the transmitted LSB and USB on another transceiver was never symetric, maybe the steps to set the bfo are not fine enough to do this or I am making something wrong.
Yes, the IF-shift is often a very helpfull feature within crowded bands and as Mike pointed out, it is also nice to be able to adjust the sound of a ssb signal on receive. So, if this could be corrected in the software would be very fine.
Another point I¡¯ve noticed today while using CW, dx-cluster and CAT to jump to a anounced station... When the CWL-, CWU-feature is enabled, then the frequency is not spot on but offset by the amount of the CW-Tone.
Nevertheless, this little rig is a joy to play with, especially with all the added features by Ian¡®s software.
Vy 73, Gerald - HB9CEY
-- Michigan VHF Corp.
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Re: The issues of the TDA2822
Well said Gordon.
Vince.
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On 03/11/2018 11:30 AM, Gordon Gibby wrote: Oh for crying out loud!
Could you folks leave this fellow alone? He¡¯s manufacturing A quality piece of equipment for chicken feed, under difficult circumstances, when nobody else rose to do the job. He¡¯s run out of parts at least twice now when the worldwide demand for his product exceeded the worldwide supply of quality components!
He didn¡¯t ask component manufactures to make him inferior parts, he simply purchase when you could find on the open market.
Once he ships it, it¡¯s beyond the pale to ask him to find a broken ones and replace them! All he can do his estimate the incidence, and try to find better component manufacturers.
If any of you want gear that is warranteed, built in first world circumstances, tested, then go pick yourself up an Icon 718 for about $650 US.
If you¡¯re not willing to learn a bit, work a bit, fix a bit, understand a bit, then please get off this man¡¯s back. It¡¯s unfair what you¡¯re doing.
Gordon L Gibby
On Mar 11, 2018, at 11:17, Christopher Miller <djmalak2k6@... <mailto:djmalak2k6@...>> wrote:
With all due respect sir, I eventually would like to purchase this kit as soon as I finish my disability claim in a month or so. This seems like a pretty serious issue. I am sure you didn't plan on parts failing but simply pointing out is only a percentage of your total production run isn't a solution.
Overall from all the posts I read this kit is great. However I suspect you realized when shipping the boards with bad audio amps that it was an issue. If the original part was less than a dollar, you can easily raise the price by .50$ to 1$ us to cover the cost of putting a good part in.
Thats just my .02$
kf4ftr Chris
-- Michigan VHF Corp.
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
Wow! Testy, aren't we? I know I said basically the same thing as you. I just explained it a little differently! It was not meant to be a criticism of what you wrote! tim ab0wr On Sun, 11 Mar 2018 12:16:05 -0400 "Vince Vielhaber" <vev@...> wrote: Did you even read what I wrote? If so, did you comprehend? You repeated the same thing I wrote.
Vince.
On 03/11/2018 10:37 AM, Tim Gorman wrote:
Vince,
If you are listening to a CW signal then moving the IF Shift doesn't change the tone of the CW signal at all. You are just moving the passband. That can change the sound of a SSB signal because you are removing some of the received audio along with the interfering signal. Just like cutting the highs or lows with a treble/bass tone control.
tim ab0wr
On Sat, 10 Mar 2018 21:07:17 -0500 "Vince Vielhaber" <vev@...> wrote:
IF Shift is supposed to shift the signal thru the passband without changing the frequency. So if you're listening to 3930 and there are signals on 3928 (it happens daily) at the same time, you can use the IF Shift to move the signals on 3928 out of the passband. If affects the sound of the desired signal like a tone control but that's a side effect of the action.
Vince.
On 03/10/2018 09:02 PM, Ronald Pfeiffer via Groups.Io wrote:
Yes I was confused a while back when Ian announced his IF shift. The code looked just like our RIT. Our RIT displays the freq on bottom line and the line above displays the plus/minus offset as you move the encoder.
rOn
------------------------------------------------------------------------ *From:* Tim Gorman <tgorman2@...> *To:* [email protected] *Sent:* Saturday, March 10, 2018 8:24 PM *Subject:* Re: [BITX20] #uBITX Firmware KD8CEC - IF-Shift etc.
I wonder if we need to define some terms here. Passband tuning and IF Shift typically move the *filter*, not the carrier. The carrier will remained tuned to the same frequency when adjusting this. For instance, if you use IF Shift when listening to a CW signal the tone of the CW signal should not change. You can move the filter bandwidth up or down to eliminate an interfering carrier that is close to the desired frequency.
What you are describing is more like an Incremental Tuning, e.g. RIT or XIT. When you move the BFO you move the carrier frequency, not the filter bandwidth.
Ideally the BFO would be set to replicate the suppressed carrier frequency. The filter then determines what is heard.
The ubitx uses a 12Mhz crystal filter. I don't know its bandwidth or what the actual absolute frequencies are. I haven't had a chance to run a spectrum analyzer against mine. Let's assume it has a 2400hz bandwidth and goes from 12,000,300hz to 12,002,700hz.
If you want to listen to a signal at 10Mhz then CLK2 should be tuned to 55Mhz to generate the 45Mhz signal the first IF needs.
CLK1 should then be set to generate a 12Mhz signal, i.e. 33Mhz. For an USB signal we should then see frequencies of 12Mhz to 12.003Mhz (or whatever the transmitted bandwidth is, e.g. 0-3000hz). You will then see frequencies of 12.0003Mhz to 12.0027Mhz out of the filter.
This is how an ideal receiver would work.
When you are talking about adjusting the BFO I assume you are talking about adjusting CLK1. If you adjust CLK1 to move the actual suppressed carrier frequency somewhere else in the filter bandwidth then your frequency indication is going to be off. What should be a 10Mhz signal is going to look like something else.
This will cause an asymmetric USB and LSB response and frequency indication.
If you want to change the BFO frequency on the fly then it should be understood as being an incremental tuning so you can remember what the base frequency should be.
Now each filter is probably going to have a different actual physical, absolute bandpass. The BFO will have to be adjusted to allow for this but the frequency indication needs to be adjusted as well to match. It should be a fixed reference, not a variable one.
Your transmitted frequency has to be offset from the CW-tone if it is to be zero beat with the received signal. If it isn't then you'll never be zero beat. I'm assuming that the CWL and CWU frequencies are indicating a frequency CW-tone away from the actual transmitting frequency. That may be because your receive BFO frequency isn't set to indicate actual carrier frequency.
I didn't mean for this to get so complicated but it isn't an easy subject.
tim ab0wr
On Sun, 11 Mar 2018 01:08:55 +0100 "ge_clipboard" <clipboard@... <mailto:clipboard@...>> wrote:
Hi All
Many thanks for all the response concerning the BFO adjustement and about using the IF-shift. I have been playing around with the BFO setting while monitoring myself on another transceiver but as I¡¯m not getting there where I really would like to, I returned to the factory settings. Leastening to the transmitted LSB and USB on another transceiver was never symetric, maybe the steps to set the bfo are not fine enough to do this or I am making something wrong.
Yes, the IF-shift is often a very helpfull feature within crowded bands and as Mike pointed out, it is also nice to be able to adjust the sound of a ssb signal on receive. So, if this could be corrected in the software would be very fine.
Another point I¡¯ve noticed today while using CW, dx-cluster and CAT to jump to a anounced station... When the CWL-, CWU-feature is enabled, then the frequency is not spot on but offset by the amount of the CW-Tone.
Nevertheless, this little rig is a joy to play with, especially with all the added features by Ian¡®s software.
Vy 73, Gerald - HB9CEY
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Re: #uBITX Firmware KD8CEC - IF-Shift etc.
#ubitx
I faintly disagree.??
Might work, but you are better off moving the VFO and the BFO, not clk1 and the BFO. If moving clk1, you change where the signal we extract is hitting the 45mhz filter.
Faintly, because the 45mhz filter is wider than the 12mhz filter. Though not terribly wide, and probably not terribly flat either. ? ?? Moving the VFO is just as easy as moving clk1, and should give at least marginally better results.
Jerry, KE7ER?
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On Sun, Mar 11, 2018 at 08:12 am, Tim Gorman wrote:
You could do the IF Shift by changing CLK1 in order to shift where the signal impacts the 12Mhz passband of the SSB filter but CLK0 would still have to maintain the same relationship to CLK2 in order to demodulate the signal properly.
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