Re: how can I order ubitx raduino?
It always has been, mine was built a year ago and came soldered down.
Could be argued that it is more reliable that way.
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On Sun, Dec 24, 2017 at 05:26 am, Jeffrey Peters wrote:
Why is the the Arduino Nano now soldered to the expansion board?听
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Re: Entry Level Bitx40 Upgrades
Without a BPF, there could be unexpected mixer products
below 80m that the LPF would not take out.
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On Sun, Dec 24, 2017 at 01:54 am, Gordon Gibby wrote:
When on 80, I 听use a very nice 听80 m lpf on output.听
听
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Re: how can I order ubitx raduino?
I would like to know how to order an extra听 Raduino board with Si5351, Arduino Nano. Fully tested for a back-up on my uBitx.
Now that the Arduino Nano is soldered to the expansion/connection board. A spare or two might be helpful to have.听 Why is the the Arduino Nano now soldered to the expansion board?听 The Nano is a plug in on the Bitx40. I am new to all of this (only been reading and learning over the past three weeks) Thank you,听 Jeff K9JP
On Sun, Dec 24, 2017 at 8:14 AM, Arvo KD9HLC via Groups.Io <arvopl@...> wrote:
-- Not all of me will die - - - The good I do will live forever.听 <><
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Re: Help! I think I may have just ruined my 9 year old's Chanukah
Gordon KX4Z wrote... 1. Lots of unused wires coming off the Raduino:
their tips may short out against the metal of the
lunchbox. Cover the ends of the unused wired with
a bit of electrical tape just like you did to protect
the Raduino against metal box. I chose to just remove all unused wires. Find the side of the connector with an open slot and press in on the metallic part with a small screwdriver or whatever and gently pull the wire out from the plastic housing. Don't lose them. They are easy enough to re-insert if you ever need a connection there in the future. -- 73 Keith VE7GDH
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how can I order ubitx raduino?
Hi,
How can I order a ubitx raduino??
Thanks,
Rod KM6SN
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Re: Entry Level Bitx40 Upgrades
Thanks very much for those corrections Jerry! 听 听When on 80, I 听use a very nice 听80 m lpf on output.听
I had some dyslexia with that integrated circuit number.
Sent from my iPhone
On Dec 23, 2017, at 22:41, Jerry Gaffke via Groups.Io < jgaffke@...> wrote:
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Great write up!
A couple minor points:
The Raduino uses an Si5351 with three outputs, not an Si5355 with 4 outputs.
(The Si5355 is not programmable like the Si5351, you are stuck with a handful of fixed frequencies.)
You suggest defeating the Bitx40's BPF with a 470pf cap so 80m signals can be heard.
That's probably ok as a hack, though you will also be receiving images about as well as the target 80m signals.
Transmitting on 80m with that BPF defeated might possibly be ok听 but I'd check the output for surprises
with a spectrum analyzer first, could easily have crud going out on other frequencies.
A much better idea is to simply replace both the BFP and the LPF with appropriate 80m filters.
Better still,听 just recommend the uBitx for those wishing to go beyond 40m.
Jerry, KE7ER
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Re: Help! I think I may have just ruined my 9 year old's Chanukah
You're very welcome for the appreciation! Gives a warm feeling.
Squeals are a common thing from that audio amplifier.....
Try putting a 1000 ohm resistor in series with the wire to the middle leg of the audio gain potentiometer. 听The exact value isn't critical, anything from 500 to 10,000 might help. 听 The original
design drags the input pin of the LM 386 Op amp 听all the way to ground with no resistance in between, and this seems to be bad.
An eight ohm speaker or higher seems to be the best. 听If you don't have anything better for a speaker, try putting a 10 ohm resistor in series with it. 听听
听
I think you've done many of them, but I wrote a couple of articles with some of the basic upgrades.
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Thank you very much to Gordon, Vince and everyone. I plan on going through this thread and everyone who helped...I'm putting your name and callsign inside the lid of this lunchbox along with Chanukah 5778... so my daughter remembers the year she got it
and the people that were a part of it....because all of you were just as much a part of this as I was.
Only question I have left....when I switch to USB, I get a high pitched squeal (I got the function switch working btw...soldered the ground onto a washer). I'm using a battery powered plug in speaker. Could that be the reason? I just need to get a proper 8
ohm speaker? I had planned to do so anyway
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Re: Help! I think I may have just ruined my 9 year old's Chanukah
Seems you all had a long night.
听
My inbox was fully loaded with messages on your journey to success.
And what a journey it was.
听
A job well done !
听
Enjoy your new radio and have fun with it.
听
Merry Christmas and wish healthy new year to you all.
听
Ron 鈥� PA3FAT
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Re: Help! I think I may have just ruined my 9 year old's Chanukah
On Sat, Dec 23, 2017 at 11:08 pm, K9HZ wrote:
So in the end鈥� following the troubleshooting video was of great help (not to take anything away from all the others pitching in).听 Guess the boys in the lab were right鈥�
To be fair, they suggested it as well. I was so overwhelmed with this that I didn't heed it. I was stressed and thought I had gotten in over my head...was afraid to do anything.听 They were working with me at my pace. To be honest, Gordon deserves most of the credit here. He correctly surmised that the problem wasn't just a broken radio... it was a beginner who thought he had bitten off more than he could chew. In the end, I just didn't fix a couple of coils... I fixed a broken wire.... I fixed a spinning bnc connector... I fixed a bad connection on a pushbutton... I learned a lot about working with the arduino IDE... I tested out my dummy load I built from a kit... In all honesty, I gained a lot more from this because it DIDN'T work the first time than I ever would have if it had just worked in the beginning. I'm not stopping here either. I'm already looking at various kits and mods. If I had just watched the video in the beginning and solved this....I wouldn't have felt like I'd done anything. I certainly wouldn't have felt like I contributed... I would have felt like I just did what I was told. Now, it's different. Gordon and Vince are to thank for that and now I know a little more about what to do if that video doesn't solve all my problems next time.
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Re: uBitx strong birdy 3.601mhz
Hello Ted, This birdy comes from internal mixing inside the Si 5351 because of common ground and its track inductance. /g/BITX20/message/35845?p=,,,20,0,0,0::Created,,F5RCT,20,2,0,4555588The relation is easy to understand : (all in MHz) Frx = 3,6 and LO1 = 3,6 + 45 = 48,6 2nd LO = 57听 and BFO is 12听 Now BIRDY = BFO - (LO2 - LO1) = 12 - ( 57 -48,6) = 3,6听 ! ! ! Since we have 3 frequencies and reciprocial mixing due to any non-linearity in Si5351 the birdies are coming from equation : BRIDIES = +/- LO1 +/- LO2 +/- BFO To reduce them :听 - As said in my post : reduce LO level to 8.5 dBm and reduce mixer atten to 2 dB uint8_t听 si5351bx_drive[3] = {1, 1, 1}; // 0=2ma 1=4ma 2=6ma 3=8ma for CLK 0,1,2 - Use highLO rejection mixer like TMF-2听 - Change or shift 1st and 2nd LO听 73 de F5RCT Jmat
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Re: Help! I think I may have just ruined my 9 year old's Chanukah
So in the end鈥� following the troubleshooting video was of great help (not to take anything away from all the others pitching in).听 Guess the boys in the lab were right鈥� 听 听 Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ 听 Owner - Operator Big Signal Ranch 鈥� K9ZC Staunton, Illinois 听 Owner 鈥� Operator Villa Grand Piton 鈥� J68HZ Soufriere, St. Lucia W.I. Rent it: Like us on Facebook! 听 听 email:听 bill@... 听
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From: [email protected] [mailto:[email protected]] On Behalf Of tausciam@...
Sent: Saturday, December 23, 2017 9:18 PM
To: [email protected]
Subject: Re: [BITX20] Help! I think I may have just ruined my 9 year old's Chanukah 听 Thank you very much to Gordon, Vince and everyone. I plan on going through this thread and everyone who helped...I'm putting your name and callsign inside the lid of this lunchbox along with Chanukah 5778... so my daughter remembers the year she got it and the people that were a part of it....because all of you were just as much a part of this as I was.
Only question I have left....when I switch to USB, I get a high pitched squeal (I got the function switch working btw...soldered the ground onto a washer). I'm using a battery powered plug in speaker. Could that be the reason? I just need to get a proper 8 ohm speaker? I had planned to do so anyway
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Re: How to deal with Broadcast FM QRM
I was able to decrease, but not completely eliminate, the 15kW AM station about 3mi from my house, by putting a .1uF from sweeper to ground on the volume pot, and a 1k in series from the sweeper to the input on the LM386. Those two together helped a lot.听
It鈥檚 definitely coming in on the audio path into the 386, not through the RF stages.听
-Mark
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On Dec 23, 2017, at 10:05 PM, Jerry Gaffke via Groups.Io < jgaffke@...> wrote: Raj is probably correct if you only hear that FM station when the volume control is set very low. His extra resistor often cures the audio frequency oscillations in the LM386 that some experience with low volume settings.听 On Sat, Dec 23, 2017 at 09:16 pm, Raj vu2zap wrote:
Sounds like the Lm386 on Bitx40.
Put a resistor on the center lead of the volume control. Try any from 1-10K. This should cure it.
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uBitx strong birdy 3.601mhz
Fired up my uBitx this evening, very strong birdy like tunable tone on 3.601Mhz.
anybody else found this?
Ted
ZL1BQA
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I had a similar problem but my rx audio was also bad. I was able to fix it by re-calibrating the bfo. The steps are on the website.
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Re: Help! I think I may have just ruined my 9 year old's Chanukah
As a bonus, I found out my dummy load kit I put together worked. I'm walking on air now.
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Re: How to deal with Broadcast FM QRM
Raj is probably correct if you only hear that FM station when the volume control is set very low.
His extra resistor often cures the audio frequency oscillations in the LM386
that some experience with low volume settings.听
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On Sat, Dec 23, 2017 at 09:16 pm, Raj vu2zap wrote:
Sounds like the Lm386 on Bitx40.
Put a resistor on the center lead of the volume control. Try any from 1-10K. This should cure it.
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Try connecting to web SDR with a receiver nearby rather than trying to listen to your audio inside the same house. I often get very distorted static listening too closely even into a dummy load. The problem may just be over loading the receiver.
听Never hurts to try
听73
听David听
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Re: How to deal with Broadcast FM QRM
Sounds like the Lm386 on Bitx40.
Put a resistor on the center lead of the volume control. Try any from 1-10K. This should cure it.
Raj
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At 24-12-2017, you wrote: I'm getting quite a bit of QRM from a nearby FM transmitter. I hear it over my digital interface as well as in my hand mic. I've observed the same thing on my VHF/UHF HTs. What's the best way to filter this out? I comes in crystal clear when I turn the volume pot all the way down - I get none of the noise from 40m, just nice clear FM. Is something in the audio chain acting as an FM detector?
Any help is appreciated.
--
David K4DBZ
Unofficial bitx chatroom:
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Try a different mic. Check the voltages on the mic amp stage.
Check the final bias. Be careful while doing this check.
Raj
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At 24-12-2017, you wrote: The speaker isn抰 the problem, my transmit audio is distorted and not sure what went wron.
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Re: How to deal with Broadcast FM QRM
Should read:听 听"I'd try adding a 0.01uF cap from LM386 pin 3 to ground, using very short leads."
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On Sat, Dec 23, 2017 at 08:38 pm, Jerry Gaffke wrote:
I'd try adding three 0.01uF cap form LM386 pin 3 to ground, using very short leads.
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Jean-Matthieu F5RCT
K9HZ
Smitty, N6MTS
N8DAH
Raj vu2zap