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Re: designer mods

 

The BITX radios are open source designs intended for hacking and learning.? They're not intended to be and likely never will be appliances.? The info's here on the forum - grab a soldering iron and join in!

Andy, KG5RKP


On Tue, Dec 18, 2018 at 10:33 AM, <mitchellmichaelh@...> wrote:
Does anyone know if the designer of the ubitx ver 4 is attempting to solve any of the problems associated with his radio?
Re: designer mods

 

Yes.

The community is also working it.

In my dreams someone will offer a kit of parts, that has been verified on maybe a couple dozen rigs.

Meanwhile,? available data may give you clues on what bands are reasonable to use.
Re: designer mods

G1WDF
 

The fact that it is V4 would suggest that improvements do occur.
There many great and wonderful minds on here working to improve the uBITX.
For that I am thankful.
Merry Christmas and a Happy New Year to you all.

Richard.
Re: calibration and tuning tweak help... #calibration #ubitx-help

 

Mark, thank you!!!!!

This is weirdly white knuckle if you are a newbie...but i will wear down the problem.?

Thank you the assistance...

Don
km4udx
Re: DSP cheap for qrp

 

?
Nice work Jack, I saw the pictures. The teensy audio library is very flexible. I am experimenting on the m4 cortex at a very low level but using the CMSIS framework, it seems good, it is not as high level as the teensy library, but it works. I saw the works of Alberto I2PHD, on Arm Radio and DF8OE (UHSDR / MCHF) and they seem very interesting, especially the UHSDR that has implemented a complex Noise Reduction, I continued the study to simplify the algorithm, still needs of "cures" but is working. See you soon, vy 73 de Giuseppe IK8YFW.
Re: DSP cheap for qrp

 

Hi Farhan, thanks for reply, obviously it is an honor for me to have your attention, thank you.
ofcourse it is possible to port it to other platforms,?
some months ago I worked on small audio processor based on Cortex M3 CPU stm32f103 it is?
extremely cheap module (less than 2 dollars), and I done first tests with filtering and simple noise reduction,
but it has not an efficient FPU and don't have a DSP hardware internal unit.?
Now using the Cortex M4, exactly the stm32f407 simple board ( the "china" price is less than 12 dollars shipped ),
I can test a more performed codes using standard opesource framework CMSIS to built a serious Noise Reduction.
I chose this hardware platform because it is very widespread and not tied to a particular vendor,?
because they are all arm cortex, so I can bring the same algorithm on Cortex M4 STM, but also Texas and so on.?
This allows to absolutely reduce the costs obtaining quality of industrial grade.
Currently I use the card stm32f407 (cost 12 dollars) a 320x200 display (cost 3 dollars) an encoder?
(cost $ 1.5) and a small circuit with 3 resistors and a capacitor (2 dollars). So a total cost less than 20 dollars.

These small cards are made to work very well with audio, implementing a Fir filter with the CMSIS platform is very simple and efficient.

The project will continue with the addition of a variable-width filter suitable for CW, SSB, digital modes and AM broadicast, hoping that the processor holds up the load.

Now I'm working to adjust the code readability then I'will share it as far as possible? on github as opensource like other projects.

I hope it can be useful. vy 73 de Giuseppe IK8YFW
Re: VA3NOI/ND6T AGC board received. Box folder found, now.... for installation?

 

Installation info on web. It shows exactly where to cut the trace to install the version with 2 mosfets. The detector attaches to the high side of the volume control. The mosfets patch into the RF signal at the front of the signal chain.

Type into search engine nd6t agc ubitx, it will take you to nd6t website.

Curt
Re: DAVE [BITX20] RF Preamp - Attenuator

Woody
 

Thanks Mike...? Found 1621s on ebay for <$6 and total of $5 for shipping.? Ordered 3.? Might take a long time for delivery.? I didn't spring for the $30-$35 shipping for three 8-pin dips!
Woody

On 12/18/2018 18:00, K5ESS wrote:
Ebay offers shipping of $2 or $3 from China.
Mike
K5ESS
Re: No audio from last week may have a solution

 

¿ªÔÆÌåÓý

Just a quick question, is it just for smoothing? Could I get by with just bridging the connection?

Sent from my Huawei Mobile


-------- Original Message --------
Subject: Re: [BITX20] No audio from last week may have a solution
From: "Curt via Groups.Io"
To: [email protected]
CC:


Sean

Glad you may have found it. Sure, bridge any similar value cap you have. You can even temporarily,? or permanently install the leaded cap on top to see if audio is restored.

I have certainly used leaded parts on surface mount boards, its nothing to fret about.

BTW smt caps when you have them tend to be easy to install with their higher mass than many other parts. But use what you have, and enjoy the radio. Good eyes in your discovery.

Curt

Re: DAVE [BITX20] RF Preamp - Attenuator

 

i suppose? ebay is offering 10pcs? smd version at less than $3 and free shipping.



On Tue, Dec 18, 2018 at 11:30 PM K5ESS <k5ess.nothdurft@...> wrote:
Ebay offers shipping of $2 or $3 from China.
Mike
K5ESS

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Woody
Sent: Tuesday, December 18, 2018 9:45 AM
To: [email protected]
Subject: Re: DAVE [BITX20] RF Preamp - Attenuator

Began to order and discovered that they want $35 shipping from Hong
Kong.? Trying to decide if I want one that bad.? ?...But thanks.
Woody

On 12/18/2018 4:14, K5ESS wrote:
> Don't know if they are authentic but you can get them (kind of expensive $6 bucks apiece on Ebay).? ?Also from Kynix for $7.25.
> Mike
> K5ESS
>
>
Re: DAVE [BITX20] RF Preamp - Attenuator

 

Ebay offers shipping of $2 or $3 from China.
Mike
K5ESS

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Woody
Sent: Tuesday, December 18, 2018 9:45 AM
To: [email protected]
Subject: Re: DAVE [BITX20] RF Preamp - Attenuator

Began to order and discovered that they want $35 shipping from Hong
Kong. Trying to decide if I want one that bad. ...But thanks.
Woody

On 12/18/2018 4:14, K5ESS wrote:
Don't know if they are authentic but you can get them (kind of expensive $6 bucks apiece on Ebay). Also from Kynix for $7.25.
Mike
K5ESS
Re: DAVE [BITX20] RF Preamp - Attenuator

Woody
 

Have used 8307s in several projects. It is a log amp with rather high freq capability which can be tamed, but it does not offer the attack / decay features of the SL621.?? Still, a possibiliity.
Woody

On 12/18/2018 15:07, BruceN wrote:
Why not take a look at the AD8307.? Seems to be comparable to the SL621.? Different package though.

Regards,

Bruce
Re: DSP cheap for qrp

Jack Purdum
 

Farhan:

Check out the video at:


Some of this is already being done.

Jack, W8TEE

On Tuesday, December 18, 2018, 12:05:19 PM EST, Ashhar Farhan <farhanbox@...> wrote:


great news. perhaps if you stick to straighr c code, we could pull this into other platforms like rpu and teensy?


On Tue, 18 Dec 2018, 18:03 Renato Martins <py2rlm@... wrote:
Thank youfor share!

FT'sss73!
Renato
py2rlm

Em ter, 18 de dez de 2018 05:57, giuseppe callipo <ik8yfw@... escreveu:

Hi Ian, I'm Giuseppe, I worked on the small project in stm32f103 based DSP last year, now I'm working on new project based on Cortex M4 processor cheap but performing, and the goal Will be ti creare a monitor with audio controlls like NR variabile filters and other stuff to help and enfatize the audio in rtx home made. Now I'm working on Noise Reduction module and have some results. The DSP tests continue, the Digital Noise Reduction DNR module is ready, in tests the audio signal is taken from a yaesu ft817 sampled at 44kHz and digitally filtered at 12kHz before being processed by the DNR module with Spectral Subtraction technique widely used in modern RTX.?
Next step are the filtering and better user interface ( i use the ic781 theme, simple and fast). When completed I will share It on GitHub.

Best 73 de ik8yfw.

Link1:

Link2:

Link3:

Link4:
Re: DSP cheap for qrp

 

great news. perhaps if you stick to straighr c code, we could pull this into other platforms like rpu and teensy?


On Tue, 18 Dec 2018, 18:03 Renato Martins <py2rlm@... wrote:
Thank youfor share!

FT'sss73!
Renato
py2rlm

Em ter, 18 de dez de 2018 05:57, giuseppe callipo <ik8yfw@... escreveu:

Hi Ian, I'm Giuseppe, I worked on the small project in stm32f103 based DSP last year, now I'm working on new project based on Cortex M4 processor cheap but performing, and the goal Will be ti creare a monitor with audio controlls like NR variabile filters and other stuff to help and enfatize the audio in rtx home made. Now I'm working on Noise Reduction module and have some results. The DSP tests continue, the Digital Noise Reduction DNR module is ready, in tests the audio signal is taken from a yaesu ft817 sampled at 44kHz and digitally filtered at 12kHz before being processed by the DNR module with Spectral Subtraction technique widely used in modern RTX.?
Next step are the filtering and better user interface ( i use the ic781 theme, simple and fast). When completed I will share It on GitHub.

Best 73 de ik8yfw.

Link1:

Link2:

Link3:

Link4:
designer mods

[email protected]
 

Does anyone know if the designer of the ubitx ver 4 is attempting to solve any of the problems associated with his radio?
Re: DAVE [BITX20] RF Preamp - Attenuator

Woody
 

Began to order and discovered that they want $35 shipping from Hong Kong.? Trying to decide if I want one that bad.?? ...But thanks.
Woody

On 12/18/2018 4:14, K5ESS wrote:
Don't know if they are authentic but you can get them (kind of expensive $6 bucks apiece on Ebay). Also from Kynix for $7.25.
Mike
K5ESS
Re: DAVE [BITX20] RF Preamp - Attenuator

Woody
 

Thanks for the lead....? Although not too cheap, sure not $250!? Will check it out.? Found a datasheet ( ). It is a pretty bad scan, but maybe enough.
Woody - KZ4AK

On 12/18/2018 4:14, K5ESS wrote:
Don't know if they are authentic but you can get them (kind of expensive $6 bucks apiece on Ebay). Also from Kynix for $7.25.
Mike
K5ESS

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Woody
Sent: Monday, December 17, 2018 8:08 PM
To: [email protected]
Subject: Re: DAVE [BITX20] RF Preamp - Attenuator

Thanks!
Be advised that my AGC amp leaves something to be desired. It works,
but needs refinement. Attack can be slow and it can pump on really
strong signals. Sure wish I had some old Plessey SL621 AGC ICs. Used
one "back in the day"... They were really great for this sort of
application, but they are no longer available.
__W__
Re: DAVE [BITX20] RF Preamp - Attenuator

 

Why not take a look at the AD8307.? Seems to be comparable to the SL621.? Different package though.

Regards,

Bruce
Re: DSP cheap for qrp

 

Thank youfor share!

FT'sss73!
Renato
py2rlm

Em ter, 18 de dez de 2018 05:57, giuseppe callipo <ik8yfw@... escreveu:

Hi Ian, I'm Giuseppe, I worked on the small project in stm32f103 based DSP last year, now I'm working on new project based on Cortex M4 processor cheap but performing, and the goal Will be ti creare a monitor with audio controlls like NR variabile filters and other stuff to help and enfatize the audio in rtx home made. Now I'm working on Noise Reduction module and have some results. The DSP tests continue, the Digital Noise Reduction DNR module is ready, in tests the audio signal is taken from a yaesu ft817 sampled at 44kHz and digitally filtered at 12kHz before being processed by the DNR module with Spectral Subtraction technique widely used in modern RTX.?
Next step are the filtering and better user interface ( i use the ic781 theme, simple and fast). When completed I will share It on GitHub.

Best 73 de ik8yfw.

Link1:

Link2:

Link3:

Link4:
Re: DSP cheap for qrp

 

Hi Ian, I'm Giuseppe, I worked on the small project in stm32f103 based DSP last year, now I'm working on new project based on Cortex M4 processor cheap but performing, and the goal Will be ti creare a monitor with audio controlls like NR variabile filters and other stuff to help and enfatize the audio in rtx home made. Now I'm working on Noise Reduction module and have some results. The DSP tests continue, the Digital Noise Reduction DNR module is ready, in tests the audio signal is taken from a yaesu ft817 sampled at 44kHz and digitally filtered at 12kHz before being processed by the DNR module with Spectral Subtraction technique widely used in modern RTX.?
Next step are the filtering and better user interface ( i use the ic781 theme, simple and fast). When completed I will share It on GitHub.

Best 73 de ik8yfw.

Link1:

Link2:

Link3:

Link4:
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