Re: [Joe] Bare Board Image
OK on all...
What I really need is confirmation of a trace location to install an
Attenuator / Amplifier I am working on.? Can't see under the relay
;)
This is the trace I think I am looking for...? TNX, Woody
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Re: UBITX Current Production (spur fix ?)
#ubitx
OK thanks for info.
Standing by for Version 5 !
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Re: [Joe] Bare Board Image
I do not believe that a bare board was ever shipped outside of units to India for assembly.? You might need to PM?Ashhar Farhan to get a photo without components.
I may be wrong on the above, but I would try that route anyway, as he is the manufacturer of the kit.
73
Evan
AC9TU?
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Re: [Joe] Bare Board Image
I may be wrong, but I don't think anyone has a bare board from HF Signals that they could scan/post images from. I've never seen one on the site and I've been watching it for just such a set of images.
I know Ashhar Farhan doesn't communicate regularly with them these days as he stated, but possibly Ashhar could get the production house to scan both sides of one before they put components on. That would, as you say, be a huge help in troubleshooting.
Jim - W0EB
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------ Original Message ------ From: "Woody" <mailme@...> To: [email protected]Sent: 12/6/2018 2:53:11 PM Subject: Re: [BITX20] [Joe] Bare Board Image Thanks Joe, These will help. Still would be nice if someone posts scanned images of bare boards. Wanted to overlay and the components are in the way...
Woody
On 12/6/2018 20:41, joel taylor wrote:
Hello Woody,
Here are a couple shots, if you have a section you need detail on, let me know and I will provide it.
On Thursday, December 6, 2018, 12:05:14 PM PST, Woody <mailme@...> wrote:
If anyone has an unassembled uBITX KIT, I sure would like to have scans
of the top and bottom. Would like pretty decent resolution, => 100 dpi
jpg files. Would make it easier to trace runs. Posting here would give
everyone access....
Thanks!
Woody - KZ4AK
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Re: [Joe] Bare Board Image
Thanks Joe,? These will help.? Still would be nice if someone posts scanned images of bare boards. Wanted to overlay and the components are in the way...
Woody
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On 12/6/2018 20:41, joel taylor wrote: Hello Woody,
Here are a couple shots,? if you have a section you need detail on, let me know and I will provide it.
On Thursday, December 6, 2018, 12:05:14 PM PST, Woody <mailme@...> wrote:
If anyone has an unassembled uBITX KIT, I sure would like to have scans
of the top and bottom.? Would like pretty decent resolution, => 100 dpi
jpg files.? Would make it easier to trace runs. Posting here would give
everyone access....
Thanks!
Woody? -? KZ4AK
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Re: spur & harmonics fix, v2
I have a two tone audio oscillator project in the queue.? Before the info on the bitx20 threads I was planning on building it to establish the maximum level for audio into the rig.? Looks like I will need to resurrect that and start some more testing.
Thank-you for the information.
Evan AC9TU
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Let me try that again...? ?Didn't mean to put photo inline.
On Thursday, December 6, 2018, 12:05:14 PM PST, Woody <mailme@...> wrote:
If anyone has an unassembled uBITX KIT, I sure would like to have scans
of the top and bottom.? Would like pretty decent resolution, => 100 dpi?
jpg files.? Would make it easier to trace runs. Posting here would give
everyone access....
Thanks!
Woody? -? KZ4AK
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Hello Woody,
Here are a couple shots,? if you have a section you need detail on, let me know and I will provide it.
On Thursday, December 6, 2018, 12:05:14 PM PST, Woody <mailme@...> wrote:
If anyone has an unassembled uBITX KIT, I sure would like to have scans
of the top and bottom.? Would like pretty decent resolution, => 100 dpi?
jpg files.? Would make it easier to trace runs. Posting here would give
everyone access....
Thanks!
Woody? -? KZ4AK
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Re: Added characters while using the keyer function
#ubitx
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Re: spur & harmonics fix, v2
When transmitting in CW mode, clk0 and clk1 get shut down.
All we have active is clk2 set to the operating frequency.? ?
Nothing for clk2 to beat against and create a spur,
so the only bad stuff in CW mode is the harmonics.
Perhaps that is why you did not see any spurs?
The spurs only occur in SSB mode, not in CW mode.
I'd feed something like a 1khz tone into the mike jack,
and adjust the signal level for the maximum peak power out?
that you expect in SSB mode.? So around 5 or 10 watts out.
Probably around 50mv. pk-pk?
The spurs get much worse as you approach the maximum possible power out,
hence the cautions here to avoid overdriving the mike.
Don't transmit continuously or you will overheat the IRF510's,
Maybe?have a helper pressing the PTT button for you periodically.
Or hack the firmware on the Nano to do this.
The Nano could also create the 1khz tone.
Jerry, KE7ER
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On Thu, Dec 6, 2018 at 10:20 AM, Evan Hand wrote:
If I did try it out, it would only confirm that the board still works (assuming I don't destroy it in making the mods).? With the simple equipment that I have (the RFExplorer SA, Siglent SDS 1102CML+ and multiple VOMS) I can not seem to detect the spurs from my board.? I suspect it is operator error, not totally the fault of the equipment.
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If anyone has an unassembled uBITX KIT, I sure would like to have scans of the top and bottom.? Would like pretty decent resolution, => 100 dpi? jpg files.? Would make it easier to trace runs. Posting here would give everyone access....
Thanks!
Woody? -? KZ4AK
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Added characters while using the keyer function
#ubitx
I have a V3 ubitx given to me and I have added a jack for an imabic keyer.? Seems to work but I am finding that it will sometimes send dah dit dit dit dah when I send the letter C.? Just a bit disconcerting. The contacts on the key have been cleaned but I? am still getting an occassional missed character when I send.? I am running KD8CEC firmware on the nano with Iambic B setting in Ian's program.? This of course does not happen when using a straight key but then there are other issues there as well.??
Thanks in advance
John AC8JW
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Re: spur & harmonics fix, v2
If I did try it out, it would only confirm that the board still works (assuming I don't destroy it in making the mods).? With the simple equipment that I have (the RFExplorer SA, Siglent SDS 1102CML+ and multiple VOMS) I can not seem to detect the spurs from my board.? I suspect it is operator error, not totally the fault of the equipment.
At some point I will screw up the courage and make the changes, however want to wait for some better smd rework equipment? and better dummy load (I hope that Mrs Santa got my list ;)
Until then I will continue to monitor and after Christmas report back on success or failure.
73
Evan
AC9TU?
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Re: UBITX Current Production (spur fix ?)
#ubitx
Can I return my V4 and get a replacement V5 ?? NOT
?
Sent from for Windows 10
?
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From this post, I assume the uBitx boards being shipped are still v4,
with no fixes for harmonics or spurs.
? ? /g/BITX20/message/62307?
Doesn't really spell out the current situation on spurs, so that's probably a "no".
However, the good news is there's a v5 board in the works, will have fixes.
Jerry
On Thu, Dec 6, 2018 at 09:12 AM, Mark Hinkleman wrote:
Does the current uBITX production version include the spur? and harmonic improvement mods that have been discussed on this group? (ie new relays, etc)
If not,? when can one expect changes to be made to be made on present production.?
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Re: UBITX Current Production (spur fix ?)
#ubitx
From this post, I assume the uBitx boards being shipped are still v4,
with no fixes for harmonics or spurs.
? ? /g/BITX20/message/62307?
Doesn't really spell out the current situation on spurs, so that's probably a "no".
However, the good news is there's a v5 board in the works, will have fixes.
Jerry
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On Thu, Dec 6, 2018 at 09:12 AM, Mark Hinkleman wrote:
Does the current uBITX production version include the spur? and harmonic improvement mods that have been discussed on this group? (ie new relays, etc)
If not,? when can one expect changes to be made to be made on present production.?
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UBITX Current Production (spur fix ?)
#ubitx
Question?
Does the current uBITX production version include the spur? and harmonic improvement mods that have been discussed on this group? (ie new relays, etc)
If not,? when can one expect changes to be made to be made on present production.?
I'm Going to buy a ubitx, but wanted to wait unit purity issues are solved.?
Thanks in advance for info
Mark NU8Z
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Re: UbitX audio hiss but no rx
Sean did reply to me in a private email.? His rig is as follows: Hi Evan,Thank you for your reply. I have a UBitx I have everything as delivered. It is the standard raduino, I believe the nano. The software is v4.3.?I have not connected directly to the Arduino yet.Keyer wise I am just hooking up a push switch to the keyer circuit. The resistor has been attached as per build instructions.The audio amp hisses, but no signal is heard. When I tube pay certain frequencies I can hear a slight pause on the audio then continue.Really not sure where to go with it. I'm just wondering if I've blown something.I somehow managed to get it to transmit in cw when trying to get it working, and it was quite close to the selected frequency, so I'd say the tuned circuit is working. I'm wondering if it is a problem with the RF input somehow connecting to the audio amp or something...Best wishesSeanSent from my Huawei Mobile
I did not know about the troubleshooting process from Ashhar,? Will need to keep that in my bag of tricks.
Thank-you Jerry
73
Evan
AC9TU
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Hi all:
I buy ubitx of some European colleague, to avoid the payment of customs, for difficulties to mount it myself.
a greeting
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Re: UbitX audio hiss but no rx
For debugging the receiver, Farhan points the way in this blog post:
? ??
He uses a 3 foot piece of wire as an antenna to pick up local QRM.
Injects that noise into each stage working back from the audio amp to the antenna,
expecting the noise to increase due to the gain in each stage.
When it does not, then we know roughly where the trouble lies.
The board probably worked when it left HFSignals, they do get checked.
Often the trouble is in broken, shorted, or cold soldered toroid wires.
Make sure sufficient enamel was removed from the wire that the solder
wicks up on the wire surface.
Did Evan's questions ever get answered??
In particular, do you still have the stock uBitx firmware installed?
Any mods done to the board?
Is it a v3 or a v4 board?
It should work out of the box, best to get it working before changing stuff.
Jerry, KE7ER
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On Mon, Dec 3, 2018 at 01:05 PM, Evan Hand wrote:
OK, I went back and looked through the prior emails to get a handle on what is going on.
First off, need to know the details of your build?
- uBitx, Bitx40, bitx20 which one if uBitx, then version (4 is the latest)
- Which version of Raduino (Nano) software are you using?
- Verify that you have installed the resistor for the CW keyer, or if using the CEC built in keyer the dual resistors for that
- did you change out the nano?
I am not sure that I can help, however will try with the above information.
Evan
AC9TU
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Re: Great Results with Mic Preamp
Thanks Paul.
I wanted to try it there to see how well it worked.? Going in, I wondered to myself how I'd know if it started to oscillate - it wasn't hard to notice.? hi hi
As it is, turning the pot more than half way is too much gain anyway.? I'm still noodling the final configuration - I'll work through your suggestions if I decide the amp stays in the box.
Thanks again!
73, Andy, KG5RKP
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On Wed, Dec 5, 2018 at 07:51 AM, Paul Dobosz wrote:
I suspect that RF is getting into the base emitter junction and causing problems.? The preamp was designed to be located inside of the microphone with nearly zero lead length between the mic cartridge and the input.? Adding a mic cable with considerable? length that couples directly to the emitter changes the situation quite dramatically as you have placed an antenna on the emitter of the 2N3904.? You are also inside the same enclosure in closer proximity to the RF output stage.
As I mentioned, the preamp circuit was a minimal design meant to fit inside of the diecast mic body so no RF bypass capacitors or ferrites were needed or included in my application.? Some measures I might suggest to mitigate are adding 1000pF bypass capacitors to the base and collector leads of the 2N3904.? If more help is needed, ferrite beads can be added in series with the collector and emitter leads.? Finally, if the issue persists, shielding may be needed to attenuate RF energy that is radiated directly into the device.? Also make sure your internal preamp grounding in low impedance at RF.
73 - Paul - K8PD
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Jim Sheldon
