¿ªÔÆÌåÓý

  1. BITX20
  2. Messages
Expanded Topics Messages Polls
Date
Re: Running on a Jump Box

 

You misunderstand me, Ralph. I don't WANT it to act the same. If I wanted that, I'd just run it directly from the jump box. But I don't want it to run away in RF, as at that level it can damage my tuner. I want it to run at 5-10 watts, not 18-20! I can control it with the amperage, and since the fuse is a 2A inline, I don't want it to run more than that. So I'm certainly not going to set it to 3A unless I want to toast marshmallows on my tuner.
Re: Known issues on uBITX r4 #ubitx

hirosmb JAZZ
 

¿ªÔÆÌåÓý

Ah, says ¡°5 Amps should suffice¡±.

// hiro, JJ1FXF



2018/06/30 2:33¡¢hirosmb JAZZ <hirosmb@...&²µ³Ù;¤Î¥á©`¥ë:

IC.


Is the one like above OK?

Thanks in advance, Ralph.

// hiro, JJ1FXF



2018/06/30 2:19¡¢Ralph Mowery <rmowery42@...&²µ³Ù;¤Î¥á©`¥ë:

You may just get by with a 2 amp supply, but I would go with at least one rated for 3 or 4 amps. It is always to have a few more amps than needed so the supply runs cool.?

On Fri, Jun 29, 2018 at 12:59 PM, hirosmb JAZZ <hirosmb@...> wrote:
Thanks, R.E.

Yes, I read about the power supply in different thread.

If I am correct, ubitx works properly with 12V 2A power supply, right?

Let me at first carefully find the one at AKIHABARA where is a famous place to buy those electric parts and devices in TOKYO.

Actually I am going to AKIHABARA tomorrow to buy some other necessary items coz I already ordered my ubitx. :)

Many thanks for your advice!

// hiro, JJ1FXF



2018/06/30 0:29¡¢R. E. Klaus via Groups.Io <reklaus@...>¤Î¥á©`¥ë:

The new audio amp in the V4 uBITS is a very common design in inexpensive audio equipment for many years. It could be sensitive to power supply voltage levels and if you are using it at below its design supply voltage it may not have enough bias current resulting in crossover distortion. The 2 solutions would be to make sure you have the proper minimum voltage applied or re-bias the outputs...add a third diode, or use a potentiometer in place of the diodes so the bias can be adjusted. In higher power systems, the 2 diodes would be in physical contact with the output transistors and would self adjust the bias as the transistors heat up to reduce the chance of thermal runaway.??


Re: RFI from uBitx TX after AGC and other mods installed

 

Those two daughter boards especially with those long wires are a sure way of inviting RF pickup especially being so near the LPFs relays.
It could be that the boards are picking RF directly by being so near the LPFs relays.
Have you tried shifting them to the front and using shielded cables for all connections?

On Thu, Jun 28, 2018 at 4:33 PM, alans77 via Groups.Io <alans77@...> wrote:
Hi Don: In an effort to eliminate the RF getting back into the audio amp I replaced the TX RF output twisted pair between the uBitx board and my PL259 with coax also switched to coax wrapped 5 turns around a 120-43 core between the volume control and the AGC board. I still hear my voice loud and clear from the speaker on 80 and 40M. I am going to look for an easy way to to mute the amp or speaker.
Re: Known issues on uBITX r4 #ubitx

hirosmb JAZZ
 

¿ªÔÆÌåÓý

IC.


Is the one like above OK?

Thanks in advance, Ralph.

// hiro, JJ1FXF



2018/06/30 2:19¡¢Ralph Mowery <rmowery42@...&²µ³Ù;¤Î¥á©`¥ë:

You may just get by with a 2 amp supply, but I would go with at least one rated for 3 or 4 amps. It is always to have a few more amps than needed so the supply runs cool.?

On Fri, Jun 29, 2018 at 12:59 PM, hirosmb JAZZ <hirosmb@...> wrote:
Thanks, R.E.

Yes, I read about the power supply in different thread.

If I am correct, ubitx works properly with 12V 2A power supply, right?

Let me at first carefully find the one at AKIHABARA where is a famous place to buy those electric parts and devices in TOKYO.

Actually I am going to AKIHABARA tomorrow to buy some other necessary items coz I already ordered my ubitx. :)

Many thanks for your advice!

// hiro, JJ1FXF



2018/06/30 0:29¡¢R. E. Klaus via Groups.Io <reklaus@...>¤Î¥á©`¥ë:

The new audio amp in the V4 uBITS is a very common design in inexpensive audio equipment for many years. It could be sensitive to power supply voltage levels and if you are using it at below its design supply voltage it may not have enough bias current resulting in crossover distortion. The 2 solutions would be to make sure you have the proper minimum voltage applied or re-bias the outputs...add a third diode, or use a potentiometer in place of the diodes so the bias can be adjusted. In higher power systems, the 2 diodes would be in physical contact with the output transistors and would self adjust the bias as the transistors heat up to reduce the chance of thermal runaway.??


Re: RF in 12v Supply

Gordon Gibby
 

¿ªÔÆÌåÓý

Make sure the ground is a healthy healthy healthy connection as well, either a chassis or some pretty thick wires and lots of them, arrange so they all connect at some point called single point ground. ?


On Jun 29, 2018, at 13:21, Lawrence Galea <9h1avlaw@...> wrote:

That's apart from Gordon's suggestion

On Fri, Jun 29, 2018 at 7:20 PM, Lawrence Galea <9h1avlaw@...> wrote:
Try RG58 for the supply.


On Fri, Jun 29, 2018 at 7:17 PM, Mark M <junquemaile@...> wrote:
The issue discussed in the 'RFI from uBitx TX after AGC and other mods installed' thread appears to be caused by RF getting into the 12v supply and from there into the 5v supply that feeds the AGC board (the ND6T/K5BCQ kit). At least that appears to be the issue on mine. I thought I'd start another thread to talk about that.

I have the ubitx in a case from . The power comes in thru a plug in the rear panel at the right of the panel (looking at it from the front), thru a fuse and then thru three wires twisted together along the rear panel to the connector on the board at the far left. There's also a polarity protect diode across the supply. The power connector is right next to the antenna connector and the supply wires run past the final transistors and .

I'm running the ubitx on 13.8v from an Astron 20A power supply, The testing was done feeding a Heathkit Cantenna dummy load.

So, any suggestions on how to fix this would be appreciated. Don mentioned heavier supply wires and capacitor at the input. I thought I'd try re-routing the supply wires inside case to get them away from the RF section. Moving the power connector to the other end of the rear panel would make the run much shorter. Other than that, I don't know. RF hardware is not my forte (I'm mostly a software guy).

Thanks....? ? Mark? ? AA7TA
Re: RF in 12v Supply

 

That's apart from Gordon's suggestion

On Fri, Jun 29, 2018 at 7:20 PM, Lawrence Galea <9h1avlaw@...> wrote:
Try RG58 for the supply.


On Fri, Jun 29, 2018 at 7:17 PM, Mark M <junquemaile@...> wrote:
The issue discussed in the 'RFI from uBitx TX after AGC and other mods installed' thread appears to be caused by RF getting into the 12v supply and from there into the 5v supply that feeds the AGC board (the ND6T/K5BCQ kit). At least that appears to be the issue on mine. I thought I'd start another thread to talk about that.

I have the ubitx in a case from . The power comes in thru a plug in the rear panel at the right of the panel (looking at it from the front), thru a fuse and then thru three wires twisted together along the rear panel to the connector on the board at the far left. There's also a polarity protect diode across the supply. The power connector is right next to the antenna connector and the supply wires run past the final transistors and .

I'm running the ubitx on 13.8v from an Astron 20A power supply, The testing was done feeding a Heathkit Cantenna dummy load.

So, any suggestions on how to fix this would be appreciated. Don mentioned heavier supply wires and capacitor at the input. I thought I'd try re-routing the supply wires inside case to get them away from the RF section. Moving the power connector to the other end of the rear panel would make the run much shorter. Other than that, I don't know. RF hardware is not my forte (I'm mostly a software guy).

Thanks....? ? Mark? ? AA7TA
Re: RF in 12v Supply

 

Try RG58 for the supply.


On Fri, Jun 29, 2018 at 7:17 PM, Mark M <junquemaile@...> wrote:
The issue discussed in the 'RFI from uBitx TX after AGC and other mods installed' thread appears to be caused by RF getting into the 12v supply and from there into the 5v supply that feeds the AGC board (the ND6T/K5BCQ kit). At least that appears to be the issue on mine. I thought I'd start another thread to talk about that.

I have the ubitx in a case from . The power comes in thru a plug in the rear panel at the right of the panel (looking at it from the front), thru a fuse and then thru three wires twisted together along the rear panel to the connector on the board at the far left. There's also a polarity protect diode across the supply. The power connector is right next to the antenna connector and the supply wires run past the final transistors and .

I'm running the ubitx on 13.8v from an Astron 20A power supply, The testing was done feeding a Heathkit Cantenna dummy load.

So, any suggestions on how to fix this would be appreciated. Don mentioned heavier supply wires and capacitor at the input. I thought I'd try re-routing the supply wires inside case to get them away from the RF section. Moving the power connector to the other end of the rear panel would make the run much shorter. Other than that, I don't know. RF hardware is not my forte (I'm mostly a software guy).

Thanks....? ? Mark? ? AA7TA
Re: Known issues on uBITX r4 #ubitx

 

You may just get by with a 2 amp supply, but I would go with at least one rated for 3 or 4 amps. It is always to have a few more amps than needed so the supply runs cool.?

On Fri, Jun 29, 2018 at 12:59 PM, hirosmb JAZZ <hirosmb@...> wrote:
Thanks, R.E.

Yes, I read about the power supply in different thread.

If I am correct, ubitx works properly with 12V 2A power supply, right?

Let me at first carefully find the one at AKIHABARA where is a famous place to buy those electric parts and devices in TOKYO.

Actually I am going to AKIHABARA tomorrow to buy some other necessary items coz I already ordered my ubitx. :)

Many thanks for your advice!

// hiro, JJ1FXF



2018/06/30 0:29¡¢R. E. Klaus via Groups.Io <reklaus@...>¤Î¥á©`¥ë:

The new audio amp in the V4 uBITS is a very common design in inexpensive audio equipment for many years. It could be sensitive to power supply voltage levels and if you are using it at below its design supply voltage it may not have enough bias current resulting in crossover distortion. The 2 solutions would be to make sure you have the proper minimum voltage applied or re-bias the outputs...add a third diode, or use a potentiometer in place of the diodes so the bias can be adjusted. In higher power systems, the 2 diodes would be in physical contact with the output transistors and would self adjust the bias as the transistors heat up to reduce the chance of thermal runaway.??


Re: RF in 12v Supply

Gordon Gibby
 

Sprinkle 0.1 ufd capacitors from supply lines to ground. They¡¯re cheap, and they¡¯re great!

On Jun 29, 2018, at 13:17, Mark M <junquemaile@...> wrote:

The issue discussed in the 'RFI from uBitx TX after AGC and other mods installed' thread appears to be caused by RF getting into the 12v supply and from there into the 5v supply that feeds the AGC board (the ND6T/K5BCQ kit). At least that appears to be the issue on mine. I thought I'd start another thread to talk about that.

I have the ubitx in a case from amateurradiokits.in. The power comes in thru a plug in the rear panel at the right of the panel (looking at it from the front), thru a fuse and then thru three wires twisted together along the rear panel to the connector on the board at the far left. There's also a polarity protect diode across the supply. The power connector is right next to the antenna connector and the supply wires run past the final transistors and .

I'm running the ubitx on 13.8v from an Astron 20A power supply, The testing was done feeding a Heathkit Cantenna dummy load.

So, any suggestions on how to fix this would be appreciated. Don mentioned heavier supply wires and capacitor at the input. I thought I'd try re-routing the supply wires inside case to get them away from the RF section. Moving the power connector to the other end of the rear panel would make the run much shorter. Other than that, I don't know. RF hardware is not my forte (I'm mostly a software guy).

Thanks.... Mark AA7TA
RF in 12v Supply

Mark M
 

The issue discussed in the 'RFI from uBitx TX after AGC and other mods installed' thread appears to be caused by RF getting into the 12v supply and from there into the 5v supply that feeds the AGC board (the ND6T/K5BCQ kit). At least that appears to be the issue on mine. I thought I'd start another thread to talk about that.

I have the ubitx in a case from amateurradiokits.in. The power comes in thru a plug in the rear panel at the right of the panel (looking at it from the front), thru a fuse and then thru three wires twisted together along the rear panel to the connector on the board at the far left. There's also a polarity protect diode across the supply. The power connector is right next to the antenna connector and the supply wires run past the final transistors and .

I'm running the ubitx on 13.8v from an Astron 20A power supply, The testing was done feeding a Heathkit Cantenna dummy load.

So, any suggestions on how to fix this would be appreciated. Don mentioned heavier supply wires and capacitor at the input. I thought I'd try re-routing the supply wires inside case to get them away from the RF section. Moving the power connector to the other end of the rear panel would make the run much shorter. Other than that, I don't know. RF hardware is not my forte (I'm mostly a software guy).

Thanks.... Mark AA7TA
Re: A Breadboard Technique for the uBITX

Jack Purdum
 

The photo is of a 5" touch screen (resistive) display (7" is an option) and the processor is the Teensy 3.6. Al (AC8GY) and I are working to finish the JackAl board for everything. I posted a desciption of the JackAl features a few days ago. The AGC (both audio and IF) requires a "non-standard" attachment to the board, but everything else works through the existing connectors. We hope t have the Beta boards going out next week.

Jack, W8TEE

On Friday, June 29, 2018, 12:51:38 PM EDT, Jon Titus, KZ1G <tituskz1g@...> wrote:


Very nice, Jack.? Have you described your setup?? I'm interested in the type of display and processor board, and the software.
--
Jon Titus, KZ1G
Herriman, UT USA

Re: Known issues on uBITX r4 #ubitx

hirosmb JAZZ
 

¿ªÔÆÌåÓý

Thanks, R.E.

Yes, I read about the power supply in different thread.

If I am correct, ubitx works properly with 12V 2A power supply, right?

Let me at first carefully find the one at AKIHABARA where is a famous place to buy those electric parts and devices in TOKYO.

Actually I am going to AKIHABARA tomorrow to buy some other necessary items coz I already ordered my ubitx. :)

Many thanks for your advice!

// hiro, JJ1FXF



2018/06/30 0:29¡¢R. E. Klaus via Groups.Io <reklaus@...&²µ³Ù;¤Î¥á©`¥ë:

The new audio amp in the V4 uBITS is a very common design in inexpensive audio equipment for many years. It could be sensitive to power supply voltage levels and if you are using it at below its design supply voltage it may not have enough bias current resulting in crossover distortion. The 2 solutions would be to make sure you have the proper minimum voltage applied or re-bias the outputs...add a third diode, or use a potentiometer in place of the diodes so the bias can be adjusted. In higher power systems, the 2 diodes would be in physical contact with the output transistors and would self adjust the bias as the transistors heat up to reduce the chance of thermal runaway.??

Re: A Breadboard Technique for the uBITX

Jon Titus, KZ1G
 

I haven't experienced any noise problems.? I still must shorten some wires and think about a final mounting arrangement.
--
Jon Titus, KZ1G
Herriman, UT USA
Re: A Breadboard Technique for the uBITX

Jon Titus, KZ1G
 

Very nice, Jack.? Have you described your setup?? I'm interested in the type of display and processor board, and the software.
--
Jon Titus, KZ1G
Herriman, UT USA
Re: A Breadboard Technique for the uBITX

 

I used a plastic cutting board and some pieces of single sided copper clad board mounted with "L" brackets as a temporary "enclosure" to mount
the board and controls ?so that I can play with mods and figure out what controls and switches I really need,?before I start cutting and drilling a permanent enclosure.?
This photo is a about a week or two old as I already have my 2.8" Nextion Display attached and mounted.?

I learned my lesson with the BITX40, I packaged it a little too early and ended up struggling a bit to find space to add extra switches to take advantage of new features as more software mods appeared.

Cheers

Michael VE3WMB?

uBITX_Cutting_board.JPG

Re: Known issues on uBITX r4 #ubitx

hirosmb JAZZ
 

¿ªÔÆÌåÓý

Arv,

Appreciated for your comments and pointers ?of details.

Certainly let me try some mods you advised after I set up my ubitx as it is.

I am not a hardware guy and so need a little more time to understand your advice.

However, it¡¯s a very good opportunity for me to know more about hardware and ubitx for sure.

Thanks a lot. I will come back to this topic when my ubitx is ready to be modified.

// hiro, JJ1FXF



2018/06/30 0:59¡¢Arv Evans <arvid.evans@...&²µ³Ù;¤Î¥á©`¥ë:

Hiro

The distortion issue seems to be more related to audio level and impedance and quality of the
attached speaker.?? Layout of the uBITX-4 audio output section allows one to make changes
like changing the idling current of the NPN-PNP output pair and adding negative feedback.? The
two emitter resistors can be shorted to give more output current, but be careful that audio level
does not overheat the output pair.? Adding a resistor for negative feedback could improve linearity.





/g/BITX20/topic/4104436?p=,,,20,0,0,0::,,,0,0,0,4104436

Arv
_._


On Thu, Jun 28, 2018 at 11:59 PM hirosmb JAZZ <hirosmb@...> wrote:
Do all of the v4 have this distortion issue? Or ?only for the certain lots?

Thanks, Andy.

Ur videos helped me to understand what the distortion issue is like.

// hiro, JJ1FXF



2018/06/29 14:47¡¢Andy V. Borisenko via Groups.Io <rw9rn@...&²µ³Ù;¤Î¥á©`¥ë:

I have ?v4.
big problems with sound.
if you bypass the built-in audio amplifier, then you can use it.
for example, a video from my uBitx v4
Re: Easy, Inexpensive Cooling Fan, Excelway Case

Jack Purdum
 

Nice...any more pictures??

Jack, W8TEE

On Friday, June 29, 2018, 11:32:58 AM EDT, Vince Loschiavo <vince320@...> wrote:


Re: Known issues on uBITX r4 #ubitx

hirosmb JAZZ
 

Yes, Bill.

As far as I know, the distortion issue comes up with only v4 ubitx, however it¡¯s just a matter of degree.

I already placed my order with DHL, while taking a train back home today! :)

I also plan to use CEC firmware which I already modified a bit to limit the frequencies to TX in accordance with Japanese regulation.

I compiled the modified firmware which successfully runs on my Arduino UNO now.

Also I ordered a Nextion LCD at eBay which presents really lovely UI/UX.

I don¡¯t think I can sleep properly tonite coz I¡¯m so much excited. :)

Thank you, all of you here who share all the information of ubitx, such a wonderful rig!

// hiro, JJ1FXF



2018/06/30 0:21¡¢Bill Cromwell <wrcromwell@...&²µ³Ù;¤Î¥á©`¥ë:

Hi,

I have V3 with a socketed audio chip labeled as Feb 2018. It worked right out of the box - as advertised. I have not had to make *any* mods at all. I do expect to install the CEC software but that is only to get some options I would like to have for CW. I am already using it for CW. I do not have distirtion, I can tune in SSB and AM stations and they are clear. Lucky me?

Wait until you have actually used your radio to decide if you 'need' mods. Most of the mods I see described are optional and only for the owners perefernces - like my plans to install the CEC software. There will be no hardware changes to mine.

73,

Bill KU8H

On 06/29/2018 12:35 AM, Mvs Sarma wrote:
There are few members who reported the good functioning of Audio amplifier.
we need to check whether the element is wrong in design or some pieces
went out with distorted output.


Regards
MVS Sarma


On Fri, Jun 29, 2018 at 9:44 AM, hirosmb JAZZ <hirosmb@...
<mailto:hirosmb@...>> wrote:

Jack,

Thanks for ur quick reply.

I read some articles of mods, but couldn¡¯t recognize which are
necessary mods for uBITX r4 board.

Does the r4 board still need to be fixed for the distortion issue?

// hiro

--
bark less - wag more
Re: Compiler warnings

 

Good rundown on warnings.

Fortunately we haven't had a new idealistic programmer decide to set the?-Werror complier flag yet. That was great fun unleashed at the worst possible moment.

Tom, wb6b
Re: Bitx 40arduino

Elmar V?ller
 

Hi raj,
again many thanks for your kindleness and help.
?I am appriciate this very much and Hope?for succesful repair.
?
When my bitx was still working I developed a combination of agc and rx muting?to prevent
the switching cracks complete.
you are interested .?
73, elmar
Gesendet:?Freitag, 29. Juni 2018 um 17:47 Uhr
Von:?"Raj vu2zap" <rajendrakumargg@...>
An:[email protected]
Betreff:?Re: [BITX20] Bitx 40arduino
Elmar,

Change the nano on the raduino and reprogram.

Raj

At 29-06-18, you wrote:

Hello raj,
I am very glad to See your fast response.
sorry to say I killed my Raduino by myself.
Build the bitx in a new case and wiring one of the normally unused cables to the 12 Volt rail.
Now I am very angry? about myself ,hi.
Not very famili?r with digital Equipment ?looking for any Solution.
vy73 -Elmar-Dl2qa g qrp 3231
?
?
Gesendet: Freitag, 29. Juni 2018 um 16:39 Uhr Von: "Raj vu2zap" <rajendrakumargg@...> An: [email protected] Betreff: [BITX20] Bitx 40arduino
Elmar, Tell us what is the problem. Raj At 29-06-18, you wrote: >Hello, >my arduino board is defect. >how i can buy a new one..? >I would be very thankful for any help. >with Kind regards >elmar?dl2qa@...
64061 - 64080 of 117075