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Date

Waiting with Bated Breath

 

All,

Got an email from DHL - uBITX kit is scheduled to arrive this Friday!

Looking forward to putting it together and trying it out. Am fantasizing making it
remote controlled - over the network. Maybe with a raspberry pi.

- Jerry KF6VB

On 2021-04-12 06:47, _Dave_ AD0B wrote:
Thanks,
Perfectly clear now.
73
Dave
ADOB [1]
Raduino bracket and Ham_Made_Keys [2]
Links:
------
[1]
[2]
[3] /g/BITX20/message/87580
[4] /mt/82036954/243852
[5] /g/BITX20/post
[6] /g/BITX20/editsub/243852
[7] /g/BITX20/leave/10189903/243852/952924773/xyzzy


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

 

Hi Pierre,

Updating the code in the spot mentioned will alert you when you go out of band (however you define it), but won't prevent you from transmitting out of band. It shouldn't be too difficult to add that functionality if you want it, though.


Reed


Re: M1 M2 M3 M4

 

Thanks,
Perfectly clear now.?
73
Dave


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

G.A.(Jerry) Minor
 

Thanks for the help. Came to the realization that long press means very long press, press and hold until value stored and menu changed. Also, thanks for the link to the manual, and for the great work.

Four freqs are helpful, allowing me to store calling freqs for 40,20, 15, and 10 meters.


Re: M1 M2 M3 M4

 

M1 M2 M3 M4 (as you show on left) are the screw hole ground pads on the PCB. Not the same as the audio nodes M1 M2 that are routed to the K3 relay.

Rgds,
Gary


Re: uBitx v.3 finals - negative feedback

John Cunliffe W7ZQ
 

It reduces the gain and thus instabilities at low frequencies.


Re: M1 M2 M3 M4

John Cunliffe W7ZQ
 

Those points go to the TR relay located on the left lower portion of the schematic if i remember right (am at work and can't look it up)

John


M1 M2 M3 M4

 

Hello all.?
There has been one small part of the schematic that has always confused me

What role does M1? and M2 play. It looks like they are grounded yet that would not make sense. As the radio receives M1 would be shorted to M2.
--
73
Dave


Re: uBitx v.3 finals - negative feedback

 

I am thinking instability. That leads to oscillations that can kill the device. Rick Campbell had some nice design articles in QST on this. Others may be out there.

Curt


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

Pierre Guillot
 

I just discovered this link today and am enjoying its study.
Refering to??lines 19 to 32 if I modify a band defination (for instance writing in line 23?{ 3500000UL, 3600000UL, 80, "80"},) will this put new edges to the 80m bands according to my IARU area and prohibit TX outside of these limits ?

73 - Pierre - FK8IH


uBitx v.3 finals - negative feedback

 

Hello everybody. I have a version 3 of the uBitx. Is the negative feedback in the finals necessary or at least useful for the stability of the push-pull amplifier? I have seen the 26db 10w amplifier by qrplabs uses the negative feedback so I guess It is a good idea to have It. But what if It is removed?


Re: Rf it's "freezing" the Ubitx ???

 

On Sun, Apr 11, 2021 at 06:24 PM, barry halterman wrote:
Andrea, I too have had that problem and RF was getting into my UBITX from the key paddle. I used some small diameter coax and a snap on ferrite to solve my issue.
Good luck
Barry
K3bo
thanks for all reply, i will try to put some ferrite to try to stop this RF,?

73 de IW0HK Andrea


Re: Farhan to give sBITX talk at FDIM

 

That's great news. I can't wait.

73
Owen
Vk5fkov

On Sun, Apr 11, 2021 at 11:54 PM Evan Hand <elhandjr@...> wrote:
I am looking forward to this talk.? I have at least one ?BITX that I plan to convert.

73
Evan
AC9TU


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

 

Hi Jerry,

I just realized the manual wasn't linked in the readme.md in the code, so I've added that link now (thanks for the nudge, Jim S). For your reference:


Reed


Re: Rf it's "freezing" the Ubitx ???

 

Andrea, I too have had that problem and RF was getting into my UBITX from the key paddle. I used some small diameter coax and a snap on ferrite to solve my issue.
Good luck
Barry
K3bo

On Sat, Apr 10, 2021, 10:44 AM Evan Hand <elhandjr@...> wrote:

Andrea,

To verify that it is an rf problem, connect it to a dummy load and see if the same thing happens.?


I solved my issues with snap on ferrites on all lines connected to the uBITX including the coax for the antenna. If that is not enough then adding .01 bypass capacitors on the mic and key lines might help.?


As Raj stated, a metal enclosure or metal tape on the inside of a plastic enclosure and a good ground will also reduce the rf feedback.?

73
Evan
AC9TU


Re: Linear Amplifier Build

 

On 2021-04-11 16:05, John Cunliffe W7ZQ wrote:
They should be easy having a gain of 20db on HF I get that much on 2m
from a pair of them.Careful though, with the gain

Indeed. That's why I always stuck with grounded grid for my tube amps. Much more stable. When I first ordered the uBITX ( impatiently waiting... ) I thought of doing a single-sweep-tube amp for it, or maybe a single 6146B. That
was before I found out just how far the solid state stuff had come.

- Jerry KF6VB


Re: Linear Amplifier Build

 

do aim for stability and cleanness over raw power - and keep in mind this simple math:

each time you increase power 4X this is 6 dB, and roughly it is one S-unit.? if we start with 10 watts, 40 watts is one S-unit stronger and 160 watts is 2 S-units total -- so don't sweat for every watt.? a small amplifier could help your ubitx - but if you seek out big signals on SSB - the funny thing is many of them can hear you as is.? I remember the central Eu station that scolded me for giving my call twice and we doubled on the second one.?

keep learning along the way.?

Curt


Re: Linear Amplifier Build

 

Jerry, KF6VB,

Ooooh, an excellent opportunity for the QRP operator.
Stuff a slingshot, a motorcycle battery, some magnet wire, and that new uBitx?
into a daypack, head on up that hill.?
That sort of thing is even easier now that winter is done.

Don't forget the six pack of beer.
You earn it doing the hike.

Jerry, KE7ER


On Sun, Apr 11, 2021 at 10:52 AM, jerry@... wrote:
*** It's a 6BTV vertical perched on the side of a hill. I'm pretty sure the hill is the problem. I used to get excellent reports from the south Pacific.


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

 

Hi Jerry,

There's no compile-time requirements to use the favorites.

To set a favorite, tune to the frequency you want to save, then short press the star icon, and finally long press the desired memory slot (on the right of the screen) to save it. To recall, press the star icon, then short press the favorite slot (again on the right) desired.

I only programmed 4 slots because that's all that would fit on the screen nicely, however there is plenty more space in the EEPROM if you wanted to modify the code to store more.


Reed


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

 

Short and long press works as for me.? Works with a press of the favorite on the screen button, or the encoder wheel function button.
There are only 4 favorites.
Rgds,
Gary