Re: #ubitx. Increasing power output
Not as good as it has low peak current capability.
the BSX20 is better suited for the earlier stages.? For? Driver the 2n2222A or 2n2219
has vastly higher peak current and the capacitance is insignificant in a properly
designed circuit.
As to the VHF roll off... ITs a 300mhz FT transistor.? The BSX20 is a 500 mhz device
so its not that much better compared to the 600mhz old standby 2n2963 or the
2n5179 1.2ghz device and if you need real performance the BFR106 at 5ghz.
Allison
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Re: Modular uBitx - "Ex: Harmonics"
Is there a concern for how the contacts are routed on the PC board so far as RF is concerned? What about the ability of the contacts to reliably switch relatively low level signals? John Brock WA8US
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I have the exact same problem. I'm planning to upgrade too, so will be interested to see if that works for you. Will watch this thread.?
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Gilles?
MY ubitx is also a V3.
Don't forget the coupling capacitor on the filter output.. I had some very strange behavior in the audio of my Bitx 40 until I figured out that the output of the filter was Dc coupled.
Cheers?
Michael VE3WMB
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my uBitx audio filter:? ? https://www.youtube.com/watch?v=v4_XrLQKBTU&t=28s
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Re: Modular uBitx - "Ex: Harmonics"
The desired signal at Q10 is always right around 45mhz.
Has to be, or it won't go through the 45mhz crystal filter
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On Sun, Aug 19, 2018 at 01:37 AM, Eric Flores wrote:
Tom, you¡¯re thinking right up my alley. I was also considering a RPi to handle digital modulation modes.?
?
But, I am also considering using it to run an RTL-SDR for all of the RX work and tap the signal from the 1 mixer (just off C10 and the base of Q10, and completey removing R10, R11, Q10) and send the RX strait to RTL w/ small piece of coax. The IF should be 46Mhz-75MHz (for 160-10m) right there, which is well within the range of the dongle so you wound not need a hamitup upconverter. The one issue that might prevent this is I can¡¯t seem to get rid of a 1/2 second delay in the RTLs.?
?
I was also considering having a headless ubitx so I can have the radio in a shack and operate from the house, which could end up being a few hundred yards away. It would be controlled via a network connection to either another RPi or a computer (possibly via rtl_tcp for RX control, a REST API for general radio control and an RTP stream for TX voice).?
?
As an added plus, raspian supports Docker so each of these little services can be their own container making upgrades a breeze.?
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Re: New file in Photo section "ubitx T11 specturm"
#ubitx
Your tones aren¡¯t balanced. Adjust the amplitude of one of your tones.
They should cross over
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On 19 Aug 2018, at 7:07 pm, Henning Weddig via Groups.Io < hweddig@...> wrote:
Jim,
Your photo does not show a good two tone signal:
the envelope should have a zero crossings. So either the two
tones are not exactlx equal, or not equal amplified (ripple within
the xtal filter!) or the carrier suppression is not sufficient!
Another possibility could be ripple and insufficient
carrier suppression.
Henning Weddig
DK5LV
Am 19.08.2018 um 06:49 schrieb Jim
Tibbits:
Spectrum of T11 for various bands ..Two-tone test (630 Hz and 2100
Hz) each 100 mV p/p ,,approx 550 ma. current draw on finals
Jim
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Re: Modular uBitx - "Ex: Harmonics"
Tom¡ª well, that 4 relay module certainly is cheap! ? And it looks like it has optically isolated controls of the relay coil¡¯s. ? That would get around the coupling back through the coil¡¯s. ? Probably even better than the inductors and bypass capacitor is that
I stuck on. That little eight dollar board runs (it seems ) on 5 V, but it wouldn¡¯t be hard to step down the TX switched voltage to 5 V to run this. ? You might could just switch the input to a 5 V regulator and it might be fast enough
I would think that that¡¯s a pretty elegant solution. Had I known about it I might have done it.
Cheers!!
Gordon
?
On Aug 19, 2018, at 05:36, Tom, wb6b < wb6b@...> wrote:
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Using the RTL_SDR sounds interesting. I'd been concerned about audio delays even with using software audio filters/equalizers. Was running this by another local ham, and he suggested that some delay would likely not be an issue, as many times Hams are
using the webSDR site to help hear people in a net that they can't hear directly.
I guess if I can respond to my call in a net roll call before the net control calls the next call, all is well. So, maybe a half a second is acceptable. But, at some point it will be troublesome. When I use OpenWebRX on my local network, it still will try to
buffer up several seconds of audio, that is something I'd need to improve for a headless radio arrangement. ?
I looked in my notes the web protocol I was looking into is called?WebRTC. Supposedly it is supported by a number of browsers, now.
Docker is cool, I use it with some of my consulting clients. I just made a clone of my Pi's SD card, so when I start stringing more audio software applications together and Jack Audio stops working and it is too perplexing to get back to a known working state,
I can just start again from a known system that has WSJT working and try again. At least to me, Linux has one of the most confusing audio chains imaginable. FLdigi seems to use a different audio backend than WSJT so getting both to work is requiring some work.
The logic of the Linux sound support may strike me as I play with it more.?
Tom, wb6b
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Re: New file in Photo section "ubitx T11 specturm"
#ubitx
Jim,
Your photo does not show a good two tone signal:
the envelope should have a zero crossings. So either the two
tones are not exactlx equal, or not equal amplified (ripple within
the xtal filter!) or the carrier suppression is not sufficient!
Another possibility could be ripple and insufficient
carrier suppression.
Henning Weddig
DK5LV
Am 19.08.2018 um 06:49 schrieb Jim
Tibbits:
toggle quoted message
Show quoted text
Spectrum of T11 for various bands ..Two-tone test (630 Hz and 2100
Hz) each 100 mV p/p ,,approx 550 ma. current draw on finals
Jim
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Re: Modular uBitx - "Ex: Harmonics"
Using the RTL_SDR sounds interesting. I'd been concerned about audio delays even with using software audio filters/equalizers. Was running this by another local ham, and he suggested that some delay would likely not be an issue, as many times Hams are using the webSDR site to help hear people in a net that they can't hear directly.
I guess if I can respond to my call in a net roll call before the net control calls the next call, all is well. So, maybe a half a second is acceptable. But, at some point it will be troublesome. When I use OpenWebRX on my local network, it still will try to buffer up several seconds of audio, that is something I'd need to improve for a headless radio arrangement. ?
I looked in my notes the web protocol I was looking into is called?WebRTC. Supposedly it is supported by a number of browsers, now.
Docker is cool, I use it with some of my consulting clients. I just made a clone of my Pi's SD card, so when I start stringing more audio software applications together and Jack Audio stops working and it is too perplexing to get back to a known working state, I can just start again from a known system that has WSJT working and try again. At least to me, Linux has one of the most confusing audio chains imaginable. FLdigi seems to use a different audio backend than WSJT so getting both to work is requiring some work. The logic of the Linux sound support may strike me as I play with it more.?
Tom, wb6b
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Re: UBITX won't key--- solved
G'day Joe......ok I think I figured out that the bootloader is installed with the nano328 version and so when I installed the new firmware that issue was resolved as well.? CW is now working on my rig also now.? Many thanks for your notes and sharing your experience.? All the best, Jeff VK3GMO
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Re: UBITX won't key--- solved
Congratulations Joe.? I have also now successfully downloaded and installed version 1.08 of the firmware.? I know what a bootloader is but not familiar with the Arduino IDE our how to use it to install the OLD BOOTLOADER.? Can you point me in the right direction to research it?? Thanks Jeff
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Hi. I¡¯ve been following and reading furiously since my purchase and construction of my v3 uBitx. It¡¯s housed inside an aluminium case and is wired to use a baofeng remote speaker mic. Other than that it¡¯s stock, for the time being.
my question is when I¡¯m listening on a number of frequencies it hoots, or oscillates, specifically on 1.900.000, 3.001.400, 3.601.800, 5.145.500 and many more, even with no antenna. I¡¯m concerned this is something I have caused, or is it a ¡®feature¡¯ of this model of radio?
im aware that it won¡¯t have the same level of smoothness of kits costing much more, and I¡¯m quite content with that as I¡¯m looking forward to implementing some mods, once I¡¯ve achieved a base level of operation.
it appears to be a great little radio for a beginner like me.
thanks for taking time to read and for any advice you can offer.
graham
M6OIB
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Re: Modular uBitx - "Ex: Harmonics"
Tom, you¡¯re thinking right up my alley. I was also considering a RPi to handle digital modulation modes.?
But, I am also considering using it to run an RTL-SDR for all of the RX work and tap the signal from the 1 mixer (just off C10 and the base of Q10, and completey removing R10, R11, Q10) and send the RX strait to RTL w/ small piece of coax. The IF should be 46Mhz-75MHz (for 160-10m) right there, which is well within the range of the dongle so you wound not need a hamitup upconverter. The one issue that might prevent this is I can¡¯t seem to get rid of a 1/2 second delay in the RTLs.?
I was also considering having a headless ubitx so I can have the radio in a shack and operate from the house, which could end up being a few hundred yards away. It would be controlled via a network connection to either another RPi or a computer (possibly via rtl_tcp for RX control, a REST API for general radio control and an RTP stream for TX voice).?
As an added plus, raspian supports Docker so each of these little services can be their own container making upgrades a breeze.?
Eric
On Sat, Aug 18, 2018 at 21:57 Tom, wb6b < wb6b@...> wrote: The reason Raspberry Pis are so inexpensive is they take advantage of the price advantage of using basically the same processor that is used in hundreds of millions of radio transceivers, already. (smartphones)?
So, a Raspberry Pi finding its way back into another transceiver (uBITX) does not seem too far of a stretch. Not necessarily for SDR I/Q processing, but running digital modes in a small radio package is a good thing. Also, there are some audio/microphone compressor/equalizer software packages that can run under Linux that might improve your SSB transmit audio without needing to add an additional analog compressor board (albeit a second USB sound adaptor).
On the RFI noise front, I found a metal case for the Pi that will go inside the bigger transceiver case.?
I like?Allison's idea of using Android tablets as a controller for the uBITX. I'm, also, looking into running a web server on my Raspberry Pi so I can operate my uBITX from either an iPhone or Android (without installing an App). Possibility borrowing a little from the web interface of OpenWebRX.? Some browsers may be capable of sending realtime audio back to the uBITX. I'm looking at the protocol that supposedly allows this.?
I've seen some commercial HF radios that let users send/receive text messages from their Smartphones. That, on Ham Radio, would certainly attract a new younger group of Amateur Radio operators to the hobby.
Tom, wb6b
?
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#bitx40 Article of BITX40 on CQ ham radio magazine of Japan
#bitx40
Hi!? FYI I have successfully obtained the technical certification of BITX40 by having added the modification to suppress of spurious of BITX40 from the relevant authority of telecommunication of Japan. I was requested from CQ ham radio magazine of Japan to write article of experience of BITX40. CQ ham radio magazine of QEX version including my article of BITX40 has been published on 19th. Aug. My article includes, ? The outline of TX and RX circuits of BITX40. ? The result of measurement of spurious of BITX40. ? Hardware modification to suppress of the spurious. ? Introducing the extension of function of BITX40 provided by PE1NWL ??Introducing the definition of source code for limitation TX frequency for Region 3 by PE1NWL ?  ?????? Cover Page of the magazine  ????????????????????? My Article 1st and 2nd pages. ???????????????????????????? Outline of Bitx40  ??????????????? My Article 5th and 6th pages ??? Hardware modification to suppress the spurious Thank you PE1NWL, Allard-san! 73! Akira JJ1EPE
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Re: Modular uBitx - "Ex: Harmonics"
I like Gordon's add-on second set of relays idea and board.? Just wondering if something like this relay board might do an acceptable job for someone wanting something ready made. Would follow Gordon's suggested uBITX board cuts and then wire one side of the filters to these relays.? I've seen some SPST relays where the center conductor is connected to the frame (don't know if that is the case with these). That could possibility be a big issue. But, as this would only be connected to one side of the filters, and both sides are switched, due to the original relays still switching the other side, with careful choice of wiring, these might work. ---  --- Tom, wb6b
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anyone played around the Orange pi plus for ham project?
can it control a dds or an SI ??
Paul
9H1FQ
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Re: Low Power Output for Hendricks BitX20A - Watt meters and Scope readings do not agree....
#bitx20
typo in my previous post, for +39dBm
should be
Take a measurement of a? 10W? signal (+40dBm)
It could be +39dBm = 7.9W
or +41dbM = 12.6W
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On Sun, Aug 19, 2018 at 03:41 PM, Glenn wrote:
Take a measurement of a? 10W? signal (+40dBm)
It could be +39dBm = 9.9W
or +41dbM = 12.6W
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Re: Low Power Output for Hendricks BitX20A - Watt meters and Scope readings do not agree....
#bitx20
Power output is notoriously difficult to measure.? To measure power out at one frequency, using an SA is probably the only way as you suggest.
But then, the SA has a Spec for level, typically +-1dB say, for the HP8560A I have. And unless it's just been calibrated, even that is of course,? suspect.? Calibration in my experience simply means that the instrument being tested falls with it's specification, not that it's absolutely accurate.
Then there is the problem of measuring the attenuators required for higher level power measurements.? An attenuator "checked" using an uncalibrated SA is also suspect.
Take a measurement of a? 10W? signal (+40dBm)
It could be +39dBm = 9.9W
or +41dbM = 12.6W
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On Fri, May 18, 2018 at 10:23 PM, ajparent1/KB1GMX wrote:
The check would be you must be putting st least 2A into (24W to the finals, ~50% efficiency)
the finals to be in the 10-12W region.
I don't ever believe scope readings as accurate. For power out I use a dummy load with a
diode detector or a 30-40 db power attenuator as I have a calibrated unit 30db and 10db
that into the spectrum analyzer gives good reading for power.? If all else fails if my 10W
dummy gets hot its likely more than 10W.? The latter with a thermometer can be calibrated
for power equal temperature using a variable power supply (DC power=RMS power).
At some point you need an instrument you can believe.
Allison
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Re: New file in Photo section "ubitx T11 specturm"
#ubitx
Also, too? single photo of rf output on load on 80 meters (two-tone test as above) 
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