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New wiring diagram version

 

Hi all,

Just FYI, I added a higher resolution SVG version of the ubitx wiring diagram to the wiki assembly page.  I always had a bit of trouble reading the existing version, even if I used the larger size PNG image; so I added this SVG version in case anyone else had trouble like I did.

There's such a lot of detailed information on the very nice wiring diagram that W4RJP did!

73 and cheers!


Mark.

Adrien F4IJA
 

Thank you Mark, so good to have a HD version !

Here is the link for you guys if you can't find it on the wiki : https://groups.io/g/BITX20/wikiimage/5204

Adrien F4IJA
 

I've noticed that the connector for antenna has error to display.

Before :


I've made some corrections :



The new file is for now attached in my post.

If you think it's a good idea to improve it that way, I can do it on my spare time.

I don't want to short circuit you Mark it you plan to do so, just let me know.

 

Bonjour Adrien,

Very nicely done merci!  Of course, feel free to add improvements all you want.  it is nice too, that you posted the changes like this so everyone can see the updates.  Maybe afterwards you can change the wiki image to this amended one so there will be the newest version there too.

Cheers,


Mark.

Adrien F4IJA
 

OK thanks Mark. It's still a work in progress but here is the version I've worked on yesterday evening. I've changed lot of texts and still going to improve !

--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Adrien F4IJA
 

Hi everyone !

OK, you'll now find the new version of the wiring diagram in the wiki : https://groups.io/g/BITX20/wiki/uBITX-Assembly

You will now be able to download an HD PDF and also, in the CAD folder you will find the SVG source file : https://groups.io/g/BITX20/files/uBITX%20CAD%20Drawings
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Jerry Gaffke
 

Good to have an alternate drawing of how to wire up a uBitx.
We often have questions here from puzzled kit builders.

However,

The 2 reverse protection diodes should be after the fuses, not before, so the fuses
will blow if the diodes conduct.  Those diodes might conduct the full current of
a small supply, in which case it could work as is.  (Though they should be Schottky diodes.)
They could fail with a short at high currents, which is also ok.  Or they could blow
molten silicon across the room and be open when you plug in your 20 Amp power
supply backwards, in which case you will destroy many parts on your uBitx.

I would instead add a schottky diode (lower forward voltage drop than a 1n4007)
in series with the fuse for the main supply into the uBitx.  We can afford to lose 0.3 volts there.

No real need for reverse protection on PA-PWR, as the IRF510's have their own intrinsic
reverse diode.  You might burn a board trace or coil between the PA-PWR connector and IRF510,
this would be easy to fix.  But reversing the main 12V into the uBitx will blow 
a bunch of stuff (including everything on the Raduino), and be very difficult to repair.

The fuse for the main supply into the uBitx should be 1 Amp, perhaps even 1/2 Amp.
But definitely not 5 Amps.  2 Amps could be about right for the PA PWR, maybe 3
if feeding it 20V.

Opinions will vary, we've had long discussions here about reverse protection.
But I doubt many will say this drawing is correct.
I have not looked hard at it beyond the power supply connections.

Jerry


On Wed, Sep 4, 2019 at 05:27 AM, Adrien F4IJA wrote:
Hi everyone !

OK, you'll now find the new version of the wiring diagram in the wiki : https://groups.io/g/BITX20/wiki/uBITX-Assembly

You will now be able to download an HD PDF and also, in the CAD folder you will find the SVG source file : https://groups.io/g/BITX20/files/uBITX%20CAD%20Drawings
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Adrien F4IJA
 

Thank you Jerry,

For now I've just reworked the drawings, based on the old one. It's better quality and very good to print.

I've some questions on my side too :

What is really the difference beetween PA PWR and +12V ?

Isn't it more simple to enpower just by the Alternate power  with a switch, connected both on PA PWR and +12V all the time, even though you power the ubitx with battery or with DC supply ?
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Adrien F4IJA
 

Jerry : that's OK, I've figured out why there is 2 power slots.

I've asked here another question though : https://groups.io/g/BITX20/topic/max_pa_pwr_voltage/33139548?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,0,33139548
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

 

Hi Adrien,

See this post:  https://groups.io/g/BITX20/message/53765

73,


Mark.

Ted
 




On Wed, Sep 4, 2019 at 12:12, Mark - N7EKU
<n7eku@...> wrote:
Hi Adrien,

See this post:  https://groups.io/g/BITX20/message/53765

73,


Mark.

Adrien F4IJA
 

Hi Jerry,

I've thinked a lot about your post and here is a diagram of the setup I want to make on my rig :


This setup gives me the possibility to choose on S2 weither to use an external PSU or not for PA PWR (if I'm a my QRA I'll have a PSU available, when on a hill only the battery).
I all cases, the battery is legacy to supply the uBitx and the uBitx is powered on by S1. Maybe it could be a good idea to have a 2 separate ways S1 to cut off both battery and PSU line).

Also, the D1 is in serie as proposed.

What do you think ?

--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Jerry Gaffke
 

Looks good to me, I like seeing a separate relatively small fuse for the main board.
Anything goes wrong there, it is much more likely to blow the fuse before blowing something on the board.

Though as I suggested earlier, there are dozens of ways to do this right.
And even more strongly held opinions on how one should do it.

Jerry


On Thu, Sep 5, 2019 at 02:27 PM, Adrien F4IJA wrote:
This setup gives me the possibility to choose on S2 weither to use an external PSU or not for PA PWR (if I'm a my QRA I'll have a PSU available, when on a hill only the battery).
I all cases, the battery is legacy to supply the uBitx and the uBitx is powered on by S1. Maybe it could be a good idea to have a 2 separate ways S1 to cut off both battery and PSU line).

Also, the D1 is in serie as proposed.

What do you think ?

Adrien F4IJA
 

I received yesterday a mail from Bob Fischer. In his idea the diode could be on the common ground, protecting that way both the 2 circuits. 

The point is to find a quite high current diode because the whole current of the uBITX (PA +ubitx) will go through it. 
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Clark Martin
 

Except that you’ll have voltage across the PA V+ and main V+.  If the PA V+ is actually negative the parasitic diode in the final transistors will conduct and you’ll have reverse voltage to the main V+ and ground.  No protection.

Use two diodes.


Clark Martin
KK6ISP

On Sep 5, 2019, at 10:24 PM, Adrien F4IJA <adrien.grelet@...> wrote:

I received yesterday a mail from Bob Fischer. In his idea the diode could be on the common ground, protecting that way both the 2 circuits. 

The point is to find a quite high current diode because the whole current of the uBITX (PA +ubitx) will go through it.

MVS Sarma
 

If thr reverse diode could be placed after fuse, 1n4007 would suffice as fuse acts


On Fri, 6 Sep 2019, 10:54 am Adrien F4IJA, <adrien.grelet@...> wrote:
I received yesterday a mail from Bob Fischer. In his idea the diode could be on the common ground, protecting that way both the 2 circuits. 

The point is to find a quite high current diode because the whole current of the uBITX (PA +ubitx) will go through it. 
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Adrien F4IJA
 

Do you think it's a good idea to put the S1 switch (the volume switch on GND instead of 12V ?

This way, it'll cut everything when powered off.

Thanks,
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Jerry Gaffke
 

Putting things like diodes and switches on the ground return back to the power supply
is a bad idea.  There are many other ways that the ground return could be completed.

For example, some power supplies will have the 12v ground return connected to the 
electrical safety ground of the three wire power plug into the wall socket. 
And your antenna coax outer braid should have a good solid earth ground as well.
So there's always a completed ground return, and the rig is always on.

A connection from a PC USB port into the Raduino could complete the ground return,
putting 3+ amps through those wires might even damage the PC motherboard.
 
Perhaps you have it powered from an automotive electrical system.
Having the rig chassis touch the any metal in the vehicle would turn the rig on.

The diode in the ground return would probably offer adequate reverse polarity
protection for the uBitx.   But I wouldn't do it.
For one, my brain doesn't work that way.

For another, all of the power supply return current might be going through your
antenna coax braid or through your computer's USB cable, since that may well
have a lower voltage drop than the 0.7 volts across a forward biased silicon diode.
Could cause trouble.  Better to spend an extra $0.02 on a second diode.

Jerry, KE7ER



On Thu, Sep 12, 2019 at 02:21 AM, Adrien F4IJA wrote:
Do you think it's a good idea to put the S1 switch (the volume switch on GND instead of 12V ?

This way, it'll cut everything when powered off.

Thanks,
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Wayne Leake
 

 

Adrien,

  feel that t is not a good idea to switch the negative power like you ask abot.
 A: is not the common practice.
 B: if the B+ (12 VC) and the PA + are different voltags, there is, IMO, a voltage differential between the B+ an PA +, so would possibly be some power feeding a part of the unit. That might or might not be a problem, and possible drain if running from batteries.
 Wayne WA2YNE
Old School Electronics


Adrien F4IJA
 

OK thanks.

I've wired my ubitx yesterday evening and I've connected the +12V through a diode after the fuse.

The S1 switch (on the volume knob is cutting the +12V. For now the PA PWR is directly supplied.

For now it's OK my ubitx is turning on :-)
--
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA