Date   
Re: UBITX - COLOUR TFT - ATMEGA - CONFIGURATION / CONNECTIVITY DIAGRAM #ubitx

Bert N8NN
 

Can you point me to the software to download into the ATMega board?  Thanks!

Is the 3.2" TFT display with an expansion board shield mounted to the Mega?

Bert

Re: Diy oscilloscope #parts

Lawrence Galea
 

On Mon, Feb 5, 2018 at 9:23 PM, Joe Puma <kd2nfc@...> wrote:
I would like to get on of these and a real one not a knockoff but I’m trying to find one build already. I’m not afraid to build the kit but I’d rather get it built at the moment. 

I’m also looking for a RF millivolt reader. I want to check some RF voltage points on my Yaesu for starters. It’s a good introduction for me to get started with using test equipment. 


Joe
KD2NFC 



On Feb 1, 2018, at 4:54 PM, Doug W <dougwilner@...> wrote:

On Thu, Feb 1, 2018 at 01:40 pm, Jerry Gaffke wrote:
Very nice of JYE-Tech to release all that, would be good karma to support them by avoiding clones.
It's more likely to work, and you are more likely to get support if it doesn't.
They specifically mention the SainSmart clone up on their website.
To build on Jerry's point, https://www.jyetech.com/Products/LcdScope/e138.php is worth a read.  I've been looking at these kits off and on and had no idea. 
I've purchased SainSmart filament in the past, never again.


Re: ubitx AGC?

Konstantinos Konstas
 

Hi there Alex.

Thanks for the info.
I am thinking of doing the same as AGC is needed with some QRO signals in the bands.
Based on the attached schematic that I use for reference I have a couple of questions.
C78 on the top schematic needs to be removed or not?
R253 needs to be changed from 10K to 1K as in the bottom schematic or not?
Of course C78 has to be removed and R70 replaced with a 2K2 one. This is obvious.

Thanking you in advance,

73 de Konstantinos, SV1ONW

Re: uBitx final amp Class AB?

K9HZ <bill@...>
 

The characteristic curves for different operating voltages are right in the spec sheets for them.  Its a simple matter to pick the proper curve Vds curve and adjust the bias to the correct operating point given the class of operation.  


Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

 

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

 

Owner – Operator

Villa Grand Piton - J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com


email:  bill@...

 


On Feb 5, 2018, at 7:45 PM, Dexter N Muir <dexy@...> wrote:

The more I read about these FETs the more they seem to behave like valves/'toobs'. A symmetrical output stage driven anti-phase each side is a form of Class B. If there's a non-linear section at turn-off/on then bias above that towards the linear Class-A. That means a small(ish) 'resting' current at Class AB. I'd go for the 10mA/side 'static' bias. 100mA is operating each side in Class A - very linear but very inefficient (more heat!), fine for the Bitx40 but not the uBitx. Has anyone investigated the 'valve-type' transfer curve(s)? How much bias to get beyond the non-linearity into linear (distortion-free) operation for spectral purity?

Re: UBITX - COLOUR TFT - ATMEGA - CONFIGURATION / CONNECTIVITY DIAGRAM #ubitx

Joe
 

Good morning, Bert

The project does not require a shield.
The 2.8 display plugs directly into atmega2560.
Others sizes of display will plug in as well

Files info located at
http://vu2spf.blogspot.ca
The url for the file is there... Githib

Joe
VE1BWV


On Tue, Feb 6, 2018, 2:13 AM Bert N8NN <bertgarcia73@...> wrote:
Can you point me to the software to download into the ATMega board?  Thanks!

Is the 3.2" TFT display with an expansion board shield mounted to the Mega?

Bert

uBITX rotary enconder

Jose Matos
 

Hi DR fellows
Just asking if anyone is thinking to change the rotary encoder of the uBITX to an optical encoder due
the not good quality of the uBITX encoder. 
can it is possible?
I found this on ebay: https://www.ebay.es/itm/Rotary-Encoder-400P-R-6mm-Incremental-Optical-Shaft-Working-Measurement-5-24V-SH/252550089532?hash=item3acd288b3c:g:uVsAAOSwmLlX4i36

best 73s
José
CT1FKN

W0EB/W2CTX Latest uBITX software release #ubitx

Jim Sheldon
 

This software is for the original uBITX Raduino with a standard (NOT the I2C) display.
The zip file contains a complete, illustrated manual in PDF format that contains
detailed instructions on implementing this version of the software.


We have totally restructured the menu to make it much easier to use.  The Nano's CPU cycle usage has been optimized for vastly better CW (a minor front panel wiring change is necessary to use this software).  Split is working (you do NOT have to be in transmit to change the transmitter's frequency) and though not available yet CAT is being worked on. Not promising CAT anytime soon but we're trying to implement it and keep CW working right.  (Not an easy task with a Nano but we want to keep from having to change out the Nano for some bigger card). Due to an easy programming trick, the keyer's dash paddle AND the Hand Key/external keyer connection has been moved to the same wire as the SSB PTT on the Raduino's digital connector (the orange wire).  This is possible since we don't normally use the CW key or paddles when in SSB mode and we don't use PTT when in CW mode.  The menu item CW:Key or CW:Pdl selects whether or not the line is used for the hand key or dash paddle.  This requires a minor wiring change and either a short adapter cable to be built for the hand key/external keyer or a separate hand key jack be added.  Either way it's an easy mod.  This change gives the analog A7 input back to the guys wanting it for an "S" meter or power/swr metering.  The blue wire (A6) remains as the dot input.  Since we don't have to select a specific threshold voltage on A6 for dot/dash/hand key and just determine key up or key down, the 2.2K and 10K resistors are no longer needed and the CW paddles work MUCH better. 

I posted the ubitx_V2_00R.zip file in the files section yesterday but there is so much stuff there that I'm posting the software again here to make it easier to locate for those who wish to use it.  Feedback is always appreciated and we hope you find the program useful. 
Jim Sheldon - W0EB and Ron Pfeiffer - W2CTX

Re: uBITX Firmware (CEC) 0.30 released (Test version). #ubitx

Je
 


 Hi, all!

A link from where to download version 0.35, please! I found only 0.33!

Regards, Emil

Re: uBITX rotary enconder

Jim Sheldon
 

Jose,
I have one of those and it outputs 400 pulses/revolution.  This may present problems for the software to read properly as the standard uBITX encoder puts out about 24 pulses/revolution.  The software to read the encoder would have to be changed to make that optical one work right.

Jim - W0EB

Re: bitx 40 cat and digital modes

R. Kuehn
 

Thanks for the reply Joe. 

What version of the firmware you are using with CAT support, or is it your own? I see there is a github repository that uses a modified version of Allard's 1.24 firmware: https://github.com/ggibby1/BitX40-1.24-FT857d, that claims to have added support, but I haven't given it a try yet.

Ralph
N9WTX

Re: ubitx AGC?

Arvo W0VRA
 

On Mon, Dec 11, 2017 at 03:48 am, Weddig, Henning-Christof wrote:
use an opamp with a gain of 10 (20 dB) and an audio AGC system using a SSM2166.
I am working on something similar for the microphone side with a SSM2167, and am doing a lot of thinking about how to do that on the RX side.  Someone recently used a programmable TI audio amp chip for compression and limiting.  I was thinking of using the SSM2167 in a similar way, and leaving the stock µB audio amp in place.

Re: Diy oscilloscope #parts

Jerry Gaffke
 

That could work fine as a high impedance probe for use with an oscilloscope or spectrum analyzer.
To use it with a DVM you will need to add a diode RF probe or similar at the output,
as what it sends out is an RF signal with the voltage 10x what it sees at the input (20dB).

The AD8307 based probes can be used directly for sniffing out low level RF if all you have is a DVM.

I haven't used any of those ebay probes, have no idea how well they work.



On Mon, Feb 5, 2018 at 09:51 pm, Joe Puma wrote:
I purchased this one. My radio tech manual shows test points up to 8v so I think this probe should cover it. The other one said 3v input max. 
 

Re: Diy oscilloscope #parts

Jerry Gaffke
 

A voltage divider formed by a couple series resistors to ground placed on the signal of interest
can be used to reduce the incoming voltage.  With that, the AD8307 could easily deal with higher RF levels. 
 

On Tue, Feb 6, 2018 at 07:54 am, Jerry Gaffke wrote:
The AD8307 based probes can be used directly for sniffing out low level RF if all you have is a DVM.

Re: uBITX Firmware (CEC) 0.30 released (Test version). #ubitx

M Garza <mgarza896@...>
 

Here is the .35 release:

Marco - KG5PRT

On Tue, Feb 6, 2018 at 9:36 AM, Philip <philip.g7jur@...> wrote:
https://github.com/phdlee/ubitx


Re: bitx 40 cat and digital modes

Joe Puma
 

I personally haven’t tried the cat functions yet but I have been following the guy who made that addition in this group. I sold my bitx40 but I am waiting for a Ubitx to try it out with. 

Joe
KD2NFC



On Feb 6, 2018, at 9:59 AM, rekuehn@... wrote:

Thanks for the reply Joe. 

What version of the firmware you are using with CAT support, or is it your own? I see there is a github repository that uses a modified version of Allard's 1.24 firmware: https://github.com/ggibby1/BitX40-1.24-FT857d, that claims to have added support, but I haven't given it a try yet.

Ralph
N9WTX

uBITX wiki

KD8CGH
 

I've been adding to the uBitx Wiki as a way to find posts on mods and software. I urge software and hardware mods authors to keep the wiki current and for others to populate the trouble shooting wiki. If we can keep the wiki current not only can we find useful topics, but we can reduce people asking the same questions over and over.
      Bob
         KD8CGH

Re: uBITX wiki

Roy Appleton
 

Link?

Roy
WA0YMH

On Feb 6, 2018 12:10 PM, "KD8CGH" <rkayakr@...> wrote:
I've been adding to the uBitx Wiki as a way to find posts on mods and software. I urge software and hardware mods authors to keep the wiki current and for others to populate the trouble shooting wiki. If we can keep the wiki current not only can we find useful topics, but we can reduce people asking the same questions over and over.
      Bob
         KD8CGH

Re: Professional Programmers

Don WB4AFP
 

I would be interested.  I have a lot of experience with all the above, and am currently retired.  I would welcome an opportunity to earn enough to fund my own projects.  Social security doesn't cover anywhere near all the projects I would like to pursue (or buy the tools all guys lust for, like a spetrum analyzer.)

Don Hyde, WB4AFP

Re: uBITX wiki

M Garza <mgarza896@...>
 

On Feb 6, 2018 12:16 PM, "Roy Appleton" <twelveoclockhigh@...> wrote:
Link?

Roy
WA0YMH

On Feb 6, 2018 12:10 PM, "KD8CGH" <rkayakr@...> wrote:
I've been adding to the uBitx Wiki as a way to find posts on mods and software. I urge software and hardware mods authors to keep the wiki current and for others to populate the trouble shooting wiki. If we can keep the wiki current not only can we find useful topics, but we can reduce people asking the same questions over and over.
      Bob
         KD8CGH

Re: uBITX rotary enconder

Jim Sheldon
 

Jose,
It will not work right.  I have one and I connected it to my Raduino to actually test it (using my home made test set).  At 400 pulses per revolution of the shat, it sends pulses to the Raduino many times too fast and you have to turn the shaft very very slow to get it to keep from jumping digits forward and backward.  It has open collector outputs and the internal pull up from the Nano does not give enough current to make the encoders output transistors work properly.
If you try to connect one of these to the uBITX you will not be very happy.  Save your money.

Jim, W0EB