Re: Double sided PCB for RF
Hello,
On my 2nd Ubitx homebrew, I used 2 planes of ground. I planned a via maximun vias to connect them.
The only change is that the ground plane of the arduino and the whole part SI5351 is isolated.
It is connected to the general ground plane (Forcement) with a weld bridge or through a shock self
As for reading on the NET, I read that the ideal is to have a star connection and therefore, a single point of connection of the "ground"
cdt
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Re: Double sided PCB for RF
if you know that data of the pcb you can make real 50 ohms striplines (or other impedances for transforming on in and output of an amp/final transistor) ... so if you go higher as shortwave then double sided and build in real 50 ohms is a must
bottom as a groundplane is a MUST DO if you go high in frequency ... no idea where and why you have read the other way around
dg9bfc sigi
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Tried your recommended troubleshooting, still showing the same results. No signals showing up on the waterfall or audible. Reinstalled the rasp image onto the sd card, nothing, updated sbitx, nothing. I am pushing signals out, but nothing coming into the sBITx.
Mr. Farhan, thank you and your team for the hard work you are doing to create this HF transceiver. I know it is in its early stages, but I love the simplicity of your design.
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Re: removing self from bitx20 forum
David, HF signals is now a usa company. We just hired our first employee and we are planning to hire more soon.? The boards are still assembled in India. They use toroids manufactured in the USA, chips made in Taiwan, with machines from Japan. Almost all components are bought from Mouser in Cincinati.? A few dollars certainly go to women who wind the toroids and two guys who test the radios. We sell this with minimal profit to encourage people to try out, modify and learn radio. Though the final design was compiled by me. Almost all the circuits are due to American homebrewers. Wes designed the TIAs especially for thr bitx. Most of the sbitx code is due to mentoring of Bob, W7PUA and Phil,KA9Q. Given all this topsy turvey nature of the world, it takes a whole world to make a radio.
Just wanted to say goodbye to everyone,and enjoy ur sbitxes,and such. Im changing paths in my Amateur radio career.
Just going to buy USA made or make it myself.
Not to be insulting to others, and none intended, i was shocked when 3 USA kit dealers emailed me back when i asked to purchase some of their boards and kits.
:summary of cut and paste of all three mom and pop shops. wont name the shops,dont need to.
""However, given the low cost competition from outside the US, it is difficult for us to justify the expense of a large batch.
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Here is one example:
?
We simply can not compete with this pricing and with recent supply chain issues and inflation, our costs have only increased.""
Meaning others have faster access to the chinese markets than USA markets.
So in order to be fair and support the small mom and pop shops, i wont be buying any radio kits anymore produced or designed outside the USA. Granted it limits my access to some kits, but I have a deep nawing feeling im doing myself right. Some may flame me but ohh well. to each his own.
Wish everyone good luck on the sbitx and the ubitxs too. I still own 3 ubitxs. but wont be purchasing more in the future. No offense to you Ashhar,you are a brilliant designer and buisness Man. A credit to the hobby.
good luck on all ur builds in the future and may you all keep the smoke in the pcb after building it . HI HI.
73
David
ac9xh
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Aaron
Thanks, that makes things a little clearer. I have never used a transverter but the important point to remember is that the tuner is essentially part of your HF antenna set up, so I would connect it to the HF Antenna socket and then connect the antenna to the tuner's output port. I imagine the input circuitry in the transverter? is already tuned or matched to 50 ohms, or close thereto.No point plugging the tuner in there.
Bill VK7MX
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No I have a 2 Meter beam.? On the transverter the coax goes from the HF rig to the transverter. Then you got two antenna jacks on the transverter, one for the VHF antenna and one for the HF antenna. The jack labeled HF ANT goes to the HF antenna. Then jack labeled? VHF ANT goes to the 2-meter antenna.? The question is should the external antenna tuner be put in line before or after the transverter or does it matter??  -- '72
Aaron K5ATG
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Re: 16x2, 16x4 display for V6
Bapi,
The KD8CEC software works with the 16x2 and 16x4 displays and comes in a version that works with both v5 and v6 uBitx.? You can get the software here:
Read the FileNameInfo.txt to get which file to use.? You want the files in the uBITXV5 folder.? The other folder is for the prior versions of uBitx.
The Arduino sketch is also in the archive.? Be sure to set the correct #defines in the ubitx.h folder for the display and version if you decide to compile the code rather than use Xloader to load the HEX file.
73
Evan
AC9TU
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Your settings file maybe corrupted. Can you reset that? See if your IF gain is zero or something.?
Good afternoon, Mr. Farhan,
So I replaced the finals and the voltage regulator¡ªno more issues with transmitting. I reset the Drive and PA bias and adjusted them per instructions. I can send a signal and hear it through a local SDR website, Utah SDR. However, my receiving appears to be dead. To get any noise floor, my IF is turned up to 90+. There are no signals on the waterfall whatsoever, and many stray signals stay put on the waterfall. Hooked up my G90, antenna is working great and I receive lots of signals. I could not test the voltage as it shuts down because when I turned it back on today my finals were completely shorted out.?
Hope all is well.
Andrew, KJ7VIS
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So your going to 5 watts out or what??? Say it ain't so!?
I don't think the wait for the solution will be long.
On 9/25/2022 5:29 PM, Niels Jalling
wrote:
Until the PA-problems is fixed we can transform the sBitx to a
usBitx !?
Remove both IRFZ24, remove C100 and C101, connect T6,6 to ground,
find track T8,1 on pcb, cut track close to T8, connect a wire from
T6,1 to PA-OUT.
Haven't tried yet but will do tomorrow.
de oz9ny, niels
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Are you proposing to use the HF antenna on the 2-meter CW net? I suggest you would be better advised to use an antenna designed for 2 meters, then as Ashhar said, you wouldn't need the tuner.
Bill VK7MX
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Re: Double sided PCB for RF
I do it all the time.? The big thing is a wire over ground is a transmission line so?
line width is important as well as in tuned circuits it add capacitance.
Even if the back is only a ground its still a two layer board and all the
rules apply.?
With that any topside ground needs to be stitched to the bottom
ground?either with vias (commercial etched) or though wires for
hand made. Also if you think there is enough of them use more.
Allison
------------------
Please use the forum, offline and private will go to bit bucket.
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Until the PA-problems is fixed we can transform the sBitx to a usBitx !?
Remove both IRFZ24, remove C100 and C101, connect T6,6 to ground, find track T8,1 on pcb, cut track close to T8, connect a wire from T6,1 to PA-OUT.
Haven't tried yet but will do tomorrow.
de oz9ny, niels
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Good afternoon, Mr. Farhan,
So I replaced the finals and the voltage regulator¡ªno more issues with transmitting. I reset the Drive and PA bias and adjusted them per instructions. I can send a signal and hear it through a local SDR website, Utah SDR. However, my receiving appears to be dead. To get any noise floor, my IF is turned up to 90+. There are no signals on the waterfall whatsoever, and many stray signals stay put on the waterfall. Hooked up my G90, antenna is working great and I receive lots of signals. I could not test the voltage as it shuts down because when I turned it back on today my finals were completely shorted out.?
Hope all is well.
Andrew, KJ7VIS
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How can I check to see if my Finals are ok??
Vince
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16x2, 16x4 display for V6
Can someone kindly guide me to Raduino software for uBITX V6 with a 16x2, 16x4 LCD display ?
Grateful thanks, 73s
de Bapi / VU2MZX?
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Re: Double sided PCB for RF
My best guess would be possible capacitance between the layers at certain frequencies. I have never had an issue doing HF stuff.? I tend to use ground planes on both sides of the board and connect them together thru either the plated holes for thru hole parts or with vias.? I also incorporate my mounting hole into the ground plane.
On Sun, Sep 25, 2022 at 1:13 PM barry halterman < kthreebo@...> wrote: Master builders, yes you. What is the consensus using double sided PCB for RF construction where the bottom of the PCB is the ground plane? I have read various comments on NOT to use this method, but my brain cells do not remember the reasoning.
TU
K3Bo
-- Paul Mateer, AA9GG
Elan Engineering Corp.
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Master builders, yes you. What is the consensus using double sided PCB for RF construction where the bottom of the PCB is the ground plane? I have read various comments on NOT to use this method, but my brain cells do not remember the reasoning.
TU
K3Bo
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I received #135 about two weeks ago and soon after the finals blew so I replaced them. The Radio powered up and I was again seeing traffic on the waterfall. I then performed the adjustments on the? DRIVE_BIAS and PA_BIAS per the instructions.
Power up voltage was 13.9 and current was 0.52 to 0.53 amps. I completed the adjustments but noted that current never was stable; a fluctuation of approximately 0.02 amps but I figured that was not an issue.
Today I performed a power output with a 50 watt dummy load and I see not transmit power on my MFJ-849 swr/power meter. This is a known work meter and was verified working after the test also.
I tested transmit power using RTTY and CW to validate the output. the power was set at 5 and 10 watts respectively. In all cases zero output power was observed.
Your assistance is appreciated.
Phil
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Before I click on the buy me button?
Hi Everyone,?
I¡¯m minded to buy the sBitx partial kit but I live in the U.K. however I am going to be at the VERON day of the Amateur at Zwolle next month. Where are the kits shipped from and what is the lead time??
Can anyone from the U.K. tell me what additional charges they had when there kit was delivered.?
Best wishes from a rather damp Budapest,?
Steve G0XAR?
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Gerard
Aaron K5ATG
Vince N2AIE
AA9GG