I've been doing a mix of CW and SSB since I got the AGC working and the side tone volume down to a usable level.? So far I'm mostly on 40 meters.
Dan, W2DLC
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ubitx, TX flapping relay...
Hello all,
Recently completed my ubitx and I'm testing it out on 40m. CW seems to work** (I added in the extra resistors to use an iambic paddle). However, I wired the mic up with the electret and switch that I received with the kit and when I key out the relay just continuously clicks on and off forever. Any ideas?
Some more details: ?- I'm using a homebuilt aluminum case, but the mic jack is dangling (I don't think this is the problem since the instructions require connecting the blue GND wire to the audio connector). ?- I tested the (CW) frequency accuracy using the spectrum analyzer function in an analog discovery 2 by coupling RF into a long wire attached to the analyzer, rather than direct input. There is some output in CW but nothing when I key the mic.
?- The mic electret is wired directly in series with the switch. Is the electret polarized? Do I need a current limiting resistor or something?
Thanks and 73, Adam // KM6PHD
"Fear is the mind killer."
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I do, much more than SSB. Even the BITX40 does a nice job. 73, Don
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Re: Right-sided relay harmonic attempted fix for v3/4 ubitx
Charged the 7AH gel cell at somewhere around 250mA for about 6 hours and bingo, I can keep 11.8 volts? at a measured (cheap SWR meter measurement!) "5 W" output.??
With a CW signal at 3.510? MHz (LSB) I then worked sequentially through a series of additional attenuator pads to try and calibrate the ICOM 718 S Meter
FIRST -- I check for "bleed through" by searching with no connection at all to the ICOM718 reciever --- while I could hear the signal (not strong, but there) -- there was ZERO indication onthe SWR meter.? ?So I think there is little bleed through in my MEASUREMENT apparatus.
All measurements have approximately 50 dB contributed by the resistive divider I built into the BNC pickoff on theHeathkit Cantenna
PAD ATTENTUATOR? ? ? ? ? ? ? ?S Meter Reading
20 db? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? S9 + 25 dB
20 + 6 dB? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? S9 +? 20 dB
20 + 6 + 20 dB? ? ? ? ? ? ? ? ? ? ? ? S9? ? ? ? ? ? ?-- so the 20 and 25 db points on the scale above S9 seem reasonably relatively accurate
20 + 6 + 20 + 6? ? ? ? ? ? ? ? ? ? ? ?S 8 & 1/2
20 + 6 + 20 + 6 + 6? ? ? ? ? ? ? ? ?S 8? ? ? ? ? ? -- so the S unit between S8 and S9 is worth about 12 dB
20 + 6 + 20 + 6 + 6 + 6? ? ? ? ? ?S 7 & 1/2? ?-- continues the trend that an S unit is worth about 12 dB on this particular radio at? that frequency
=? 20 + (44 db)
Note that the last line is 20 +? 44 db -- roughly right at the FCC requirement if the fundamental is at S9+25 --- so if the fundamental is at S9+25, the goal is to get all spurious responses below S 7.5 on this meter.? ?
Within homebrew accuracy anyway.....
I think this is correct thinking....
Gordon Gibby
Gordon Gibby
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Re: Harmonics measured by Warren. How bad?
Ashhar, Did you see Howard Fidel's suggestion that the filters could be recalculated to account for the added capacitance of the relays? Original post and comments here #56495 It's certainly an interesting idea- haven't heard of his theory yet being tested but even if not a complete solution it's another arrow in the quiver. John KC9OJV
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Re: Ubitx V3 Please Help, ANTENNA Pins on PCB have SHORTED no Receive
#ubitx
#ubitx-help
?OHH!! I look here at this post and can see many answers !! First I must say THANK YOU THANK YOU THANK YOU @ all 3 People here who helps me so much!
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On Sat, Aug 25, 2018 at 04:38 AM, Howard Fidel wrote:
Fabian:
If you look at he schematic, you will see that the antenna connects
to T2 through the relays and a Low pass filter. It should present a DC
short. However for RF this is OK since the transformer is normally
not a short
Ah Ok thanks now i understand this.. Yes ok i know now again: you will always learn new things in life.
If you could describe your problem in more detail maybe we can help you. Does your Raduino work? Do you hear any signals? Etc.Howard
Yes the Raduino works,.. I think it works when the LCD screen works and the menu is operable, just as I see it in youtube videos in others, so should work it?? Sound works, the TDA2822 FCI Chip seems to be ok and not blowed when i can hear a rushing sound. and i only heared somethime a am radio station from a few thousend km far away.. lol, on this day i thought, it goes be alright and i can hear ssb signals in next time but no ssb signal ever heared.. and i can hear tones like a jt65 sound or so at 10.098 Mhz a few times.. all others that i heared was only "piep pieeep" like a space computer sound, sorry for my description but i think you know what i mean.. On Sat, Aug 25, 2018 at 04:41 AM, Bill Cromwell wrote:
Hello Fabian,If you trace the circuit from the antenna it will lead you through several relay contacts to an inductor to ground. That is a piece of wire that wraps around and around with or without a core. Your meter uses direct current to measure resistance and continuity. Direct current sees any inductor as a plain old piece of wire - a short. So it sees that inductor to ground as a dead short. At RF frequencies however, it is NOT a short. Most - maybe all - radios will have this:)
Ok thank you, too now i am know this and i'm verry happy to know everything new from HAM and Radio technics.
So you should continue looking elsewhere for the problem.Have you completed the "alignment" steps? If the oscillators are far off frequency the radio will not work very well if at all.
I tried to set the BFO in the menu by display and the IRF510 (RVF2 + RFV3) current to measure and adjust with a screwdriver, but I still needed help. And I would have to readjust the Raduino on the knob (P2) but I would also need some tips for that.
Do you have a more experienced ham there who can help you?
Not really.. But today, later he say, a Ham would help me to test a few transmissions from him to me and i should say when receive..
Fabian, we all have or had different 'starting' places. It is not reasonable to assert that a kit is not for a beginner! At one time if hams did not make their own radios from scratch (not even a kit) they had no radio at all. The uBitx is not really so much of a kit. Building your own gear from scratch or from a kit is 'learning by total immersion'. Sometimes that method can seem frustrating but eventually we all get where we want to be. Just relax and enjoy the 'journey'. After you have finally sorted out the trouble and corrected it you will find it more satisfying than that Kenwood or Yaesu:) Those have their own rewards and can be an appropriate starting place for somebody else.I started out building radios from a pile of old junk harvested from dead radios. At times it was discouraging but in the end it doesn't seem to have hurt me:)
Sorry i unterstand and this is real you say. I didn't mean to say it was bad. I even collect a lot of bulky waste myself, such as radios and other electrical appliances and then solder them together and really like to make things. And doesn't want to be a "plug socket - amateur". So I have something to apologize for with the wrong wording.
And now about your English. Your English is very usable for a non native English user. I know only a few German words and not very much about the grammar or syntax. If I was suddenly transplanted to Germany I would experience 'total immersion' and would soon be speaking, reading, and writing German. It would sometimes seem frustrating but eventually I would fit right in :) For now your English is substantially better than my German.73,Bill KU8H
ok Thank you! On Sat, Aug 25, 2018 at 05:14 AM, Lawrence Galea wrote:
Fabian
you will always get a DC short across the antenna terminals.
If you follow the circuit from the two antenna connectors one is earth, on receive the other goes from K3 contact 12 to 14 to K1 contact 12 to 14 to L1, L2, L3, L4 of the Low Pass Filter to T2 winding one side marked number 1 through the coil marked side number 6 to earth.
On Transmit the winding of the output transformer T11 marked number 2 is earth, the other side of the winding marked number 6 goes to KT1 contact 12 to contact 16 and then through the respective Low Pass Filter depending on which band you are transmitting.
As you can see there is always continuity through the various coils and you will always get a DC short across the antenna terminals both on receiving and transmitting.
Thank you too i would say to you for your help, thanks! i did the measurement but in the switched off state and in the switched on state and measured the board for short circuits and at both times the short circuit... but i think this is then immediately explainable as you and the other 2 HAM had explained it...?
As for not receiving anything, did you connect an antenna to the transceiver?
Yeah Antenna is Dipol for 10m ans Dipol for 80m and i should say that i never have transmit, only receive..
Regards
Lawrence
Thank you very much!! So...ok Now I hope my answers have bring new Ideas and tips.. thank you all for new help again
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Re: Harmonics measured by Warren. How bad?
Hmmm...built and modified the Bitx40, now awaiting the ubitx. I didn't see this thread before ordering, but it will be an interesting learning experience. I shall have to see what the harmonics and spurs look like on my unit. Has anyone done any tests on what an l-match ATU does, if anything, to reduce the spurs and harmonics..ie...looking at the entire system, not just the board itself? Personally, I'm fine with adding external lpf on the antenna as well. I shall also see what my 40 - 15 mag loop does with its extremely sharp tuning.? Modern tequniques (wide band amps) are great, but maybe there is something to be said for the old 'dip and load' of my dx20 and dx60 that I used in the stone age. Thanks to all for posing test results. Makes you wonder how we survived in an Era when many of us only had a VOM for test equipment. When I think of some of the things I did as a new ham at age 15, the term 'smoke and flash' takes on a whole new meaning....
Again, thanks for the info
Brent
VE3CUS
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Re: UBITX won't key--- solved
Thanks, Joe,
How do you (or I actually) get to the iambic a and b page?? That's where I think the block may be.
Straight key is working, and so is the dot side of the keyer. No dashes, paddle and resistor are good.
Eddie
WA4JXL
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I have been using my V3 uB on CW only and have it working very well. ?But, I have never even heard another one on CW, let alone worked one. ?Is anyone else CW active with theirs?
73,
Tom ?W1EAT
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Re: Homebrew from scratch
#ubitx
And so many of them!
Don¡¯t like one? Adopt another!
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Re: 4000 mile phone qso on 20m
How 'bout the guy in Japan who got DXCC using 500milliwatts!
Jack, W8TEE
On Sunday, August 26, 2018, 9:54:38 AM EDT, Bill Cromwell <wrcromwell@...> wrote:
Hi,
During a QSO with a Swedish ham (with both of us at our homes) he told
me he had a QSO with a U.S. ham in Oklahoma from Sweden on SSB using 15
meters and 200 milliwatts! So much for large Varian tubes being required
for DX. I was using 2 watts and he was using 3.
73,
Bill? KU8H
Michigan QRP Club
On 08/26/2018 09:38 AM, iz oos wrote: > If you get a 57 with an IC-7851 it is the absolutely normality to > receive a 55 report with the Ubitx from the same station. You get what > you pay hihi... > > > Il 26/ago/2018 12:33, < davesters@...> <mailto: davesters@...>> ha scritto: > >? ? Got my first european? phone contact on my ubitx yesterday. > >? ? It was on 20 meters to a ham in Scotland. It was just a quick call >? ? sign and signal report exchange. We are deep in the heart of the USA. >? ? I was running a wire dipole? about 45 feet up. > >? ? I have had lots of contacts in the past internationally on FT8? but >? ? this is the furthest on phone with this machine. >? ? I log on QRZ. > >? ? Overheard on ham say on the air that you need a amp to do phone dx. >? ? Ah OK I got a 55 signal report > >? ? Have heard that there a CME has hit earth over night so maybe things >? ? will be different today. >? ? 73 >? ? Dave >? ? K0mbt > > -- bark less - wag more
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Re: 4000 mile phone qso on 20m
Hi,
During a QSO with a Swedish ham (with both of us at our homes) he told me he had a QSO with a U.S. ham in Oklahoma from Sweden on SSB using 15 meters and 200 milliwatts! So much for large Varian tubes being required for DX. I was using 2 watts and he was using 3.
73,
Bill KU8H
Michigan QRP Club
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On 08/26/2018 09:38 AM, iz oos wrote: If you get a 57 with an IC-7851 it is the absolutely normality to
receive a 55 report with the Ubitx from the same station. You get what
you pay hihi...
Il 26/ago/2018 12:33, <davesters@...
<mailto:davesters@...>> ha scritto:
Got my first european phone contact on my ubitx yesterday.
It was on 20 meters to a ham in Scotland. It was just a quick call
sign and signal report exchange. We are deep in the heart of the USA.
I was running a wire dipole about 45 feet up.
I have had lots of contacts in the past internationally on FT8 but
this is the furthest on phone with this machine.
I log on QRZ.
Overheard on ham say on the air that you need a amp to do phone dx.
Ah OK I got a 55 signal report
Have heard that there a CME has hit earth over night so maybe things
will be different today.
73
Dave
K0mbt
--
bark less - wag more
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Re: 4000 mile phone qso on 20m
If you get a 57 with an IC-7851 it is the absolutely normality to receive a 55 report with the Ubitx from the same station. You get what you pay hihi...
Il 26/ago/2018 12:33, < davesters@...> ha scritto: Got my first european? phone contact on my ubitx yesterday.
It was on 20 meters to a ham in Scotland. It was just a quick call sign and signal report exchange. We are deep in the heart of the USA.
I was running a wire dipole? about 45 feet up.?
I have had lots of contacts in the past internationally on FT8? but this is the furthest on phone with this machine.?
I log on QRZ.?
Overheard on ham say on the air that you need a amp to do phone dx. Ah OK I got a 55 signal report?
Have heard that there a CME has hit earth over night so maybe things will be different today.
73
Dave
K0mbt
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Re: 4000 mile phone qso on 20m
Wow! ? Thanks for the report! ?
Gordon
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Got my first european? phone contact on my ubitx yesterday.
It was on 20 meters to a ham in Scotland. It was just a quick call sign and signal report exchange. We are deep in the heart of the USA.
I was running a wire dipole? about 45 feet up.?
I have had lots of contacts in the past internationally on FT8? but this is the furthest on phone with this machine.?
I log on QRZ.?
Overheard on ham say on the air that you need a amp to do phone dx. Ah OK I got a 55 signal report?
Have heard that there a CME has hit earth over night so maybe things will be different today.
73
Dave
K0mbt
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Re: Right-sided relay harmonic attempted fix for v3/4 ubitx
Fascinating programmable attenuators! ?Thank you guys for the education. ?
Discovered the likely cause of my low power output: gell cell battery is only putting out about 9 V under load. ?Another gell cell that has fooled me.?Charging that now. ?If unsuccessful, will switch to either a lawn tractor battery or a calibrated switching
supply.? ? ??
The joys of experimentation.?
I have a bunch of 6 dB fixed attenuators, and one more 20 DB attenuator. ? I was going to try to run a rough calibration curve on the S meter at fundamental frequency. ? Also prove the isolation of the set up by measuring S meter ?with nothing connected
to the radio.?
However all that will have to wait until I have a valid power source.
Cheers,
Gordon
On Aug 26, 2018, at 04:01, Tom, wb6b < wb6b@...> wrote:
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Another thought, rather than try to raise the harmonics to match the fundamental, with the likely overload issue. Maybe, I could lower the gain after I measure a harmonic so the fundamental will match the harmonics. Avoiding overload, but pushing measurements
more in the direction of the noise floor of the dongle. Again, just have to try it to see what works best. Nice thing about using a computer to drive this thing it does not have to follow a linear sweep sequence, it can jump around and play with the attenuator.
And do some other math to remove the images, mirrored around 14Mhz, if I use the "direct" mode of the dongle.?
Tom, wb6b
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4000 mile phone qso on 20m
Got my first european? phone contact on my ubitx yesterday.
It was on 20 meters to a ham in Scotland. It was just a quick call sign and signal report exchange. We are deep in the heart of the USA.
I was running a wire dipole? about 45 feet up.?
I have had lots of contacts in the past internationally on FT8? but this is the furthest on phone with this machine.?
I log on QRZ.?
Overheard on ham say on the air that you need a amp to do phone dx. Ah OK I got a 55 signal report?
Have heard that there a CME has hit earth over night so maybe things will be different today.
73
Dave
K0mbt
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Re: Right-sided relay harmonic attempted fix for v3/4 ubitx
Another thought, rather than try to raise the harmonics to match the fundamental, with the likely overload issue. Maybe, I could lower the gain after I measure a harmonic so the fundamental will match the harmonics. Avoiding overload, but pushing measurements more in the direction of the noise floor of the dongle. Again, just have to try it to see what works best. Nice thing about using a computer to drive this thing it does not have to follow a linear sweep sequence, it can jump around and play with the attenuator. And do some other math to remove the images, mirrored around 14Mhz, if I use the "direct" mode of the dongle.?
Tom, wb6b
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Re: Right-sided relay harmonic attempted fix for v3/4 ubitx
That is a good price. The chip is an "obsolete" chip, but does not matter. Only 0.5 DB steps, but that is more than needed.?
With my Google Translate App, with some humorous variations in the translation, I can read the label.?
So, yes, maybe I'll give my eyesight a break.
Tom, wb6b
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Re: Right-sided relay harmonic attempted fix for v3/4 ubitx
On Saturday, August 25, 2018, 8:36:21 PM PDT, Gordon Gibby <ggibby@...> wrote:
All I have is the little LCD screen of the ICOM 718....but the readings were quite steady and the tuning in of the signal was not critical at all.?For the very first crack at? this EVER in my life, I was much more impressed with the measurement setup than I was with the problems I was inhaving the little uBitx to perform for me to allow testing.? Thanks, gordon gibby kx4zt
Before getting too far down the road ...IMHO very few recievers have any sort of "calibrated" s meter ..Best way is to do what you did, between the 50db tap and measureing reciever ..install a few switchable attenuators ..I prefer 3-6-10-20-20 sequence ..measure f0 set attenuation for s9 ..tune to 2f0 remove attenuation to s9 -- 2f0 is x db(given by attenuation removed) below f0 ...
jim
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Re: Right-sided relay harmonic attempted fix for v3/4 ubitx
Perhaps this module can save your vision and speed up setting up your measurements:
see:? $14.70?Free Shipping
73's
--Ron? ?N7FTZ
On Sat, Aug 25, 2018 at 11:25 PM Tom, wb6b < wb6b@...> wrote: Hi Gordon,
Glad you are feeling better. I'm looking forward to your results.
On a side note, I don't have a second quality receiver to use so I'm going to try to see if I can concoct a spectrum analyzer from a RTL-SDR dongle. I have no idea how accurate any purported DB levels from any dongle/SDR software will be, so I've been looking around for a step attenuator to buy or build.?
I ran across these amazing (and inexpensive) things.??don't know if they may be of any help to you making your measurements. Ordered a couple from Digi-key and they came in a few days.?
In my case I'm going to use two of them (plus an voltage divider like you described) to get a 60+ DB adjustable attenuation range to attempt to calibrate my dongle/SDR and to step the attenuation back down to match the fundamental to get more accurate harmonic measurements. I may need a microscope to solder wires to them, dead bug style. The big issue that will likely need a solution will be the dongle, unlike a ?good receiver, will likely overload on fundamental when I reduce then attenuation to measure the harmonics. Won't know until I try.
Tom, wb6b
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Don, ND6T
sdr freak
Brent Seres/ VE3CUS
_Dave_ AD0B