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Basic board test: 130ma @ 12.5 volts #ubitx

Don - KM4UDX
 

Hello!! New uBitx V4 builder here.  Instructions call for a plain board power up with no connections beyond power Jack. So I have no plug in cables at all. No ardunio. Nada. zip attached.  With power 12.5v I get 130ma.  This is above specs of 80-100ma. Is the extra 30ma due to the extra half volt above 12? Or do I have a problem someplace?   Thank you all VERY much.

Don
Km4udx

Ashhar Farhan
 

Do plug in the raduino and wire it up properly before measuring the current. You may even damage the board as many digital lines would be afloat.
- f

On Thu, 12 Jul 2018, 05:30 Don - KM4UDX, <dontAy155@...> wrote:
Hello!! New uBitx V4 builder here.  Instructions call for a plain board power up with no connections beyond power Jack. So I have no plug in cables at all. No ardunio. Nada. zip attached.  With power 12.5v I get 130ma.  This is above specs of 80-100ma. Is the extra 30ma due to the extra half volt above 12? Or do I have a problem someplace?   Thank you all VERY much.

Don
Km4udx

derek (G4VWI)
 

Hi Don, Ashhar.

I am also starting to put together the v4 board at the moment and am surprised to see on the HF signals (hfsignals.com/index.php/ubitx-wire-up/) wire-up page a check of the boards quiescent current prior to wiring!
Can you clarify as to why this has been left up with pictures on the site if the board can be damaged by doing this?
I am hoping this has not caused a problem.

Having machined out the rear panel I need to work out how best to mount a Nextion display as there is a 3mm strip along one edge not used as part of the "Active Area". Not sure if to make the cut-out smaller or not. Any ideas?

Derek
G4VWI.




hirosmb <hirosmb@...>
 

Don,

The WIRE-UP instruction of hfsignals.com says “between 90ma and 110 ma”.

My V4 was 85.25mA with 12.25V 5A power supply.

I forgot who, but someone here said, it’s better not to power up the plain board for long time.

I tested within 5 seconds only for a few times.

// hiro, JJ1FXF



2018/07/12 9:00、Don - KM4UDX <dontAy155@...>のメール:

Hello!! New uBitx V4 builder here.  Instructions call for a plain board power up with no connections beyond power Jack. So I have no plug in cables at all. No ardunio. Nada. zip attached.  With power 12.5v I get 130ma.  This is above specs of 80-100ma. Is the extra 30ma due to the extra half volt above 12? Or do I have a problem someplace?   Thank you all VERY much.

Don
Km4udx

Don - KM4UDX
 

Hum.....the build instructions say NOTHING about plugging in the raduino BEFORE the current test.  So I didn't plug the board in -- and did the test per instruction. 

If if this is an important caution, why not just say..."plug in raduino then do test".  Why leave us to guess and be stupid? 

So so I was stupid. 

Jerry Gaffke
 

Not stupid.

It's not in the instructions.
Also, the photo clearly shows no Raduino plugged in.
    http://www.hfsignals.com/index.php/ubitx-wire-up/
Seems Farhan wrote that 7 months ago, and this has all since slipped his mind.

There's nothing that would be damaged if a uBitx main board were powered up
without a Raduino plugged in.  

Looking at the Raduino connector on the uBitx main board schematic near the bottom of this webpage:
    http://www.hfsignals.com/index.php/ubitx-circuit-description/
there are signals for  T/R, TXA,TXB,TXC, CLK0,CLK1,CLK2, CW-KEY, and CW-TONE.


The relay driver at Q15 for T/R won't have any current going into the base,
so that transistor won't be on.  The rig will not be trying to transmit.

Likewise for the LPF band-switching relays at TXA,TXB,TXC.
Though if some of them were on we don't really care.

Perfectly fine that the three clocks are dead, that won't hurt anything.

CW-KEY won't be unbalancing the first mixer because there's no current going in there.
Doesn't really matter anyways because T/R does not have us in transmit mode.

CW-TONE is fine if there's no current going in. 
And would be fine if 5v was applied there anyways.

You might think we could have damage if T/R was somehow injecting current
into Q15, which would power up the transmit amp with inappropriate LPF filters selected by the relays.
However, with all clocks dead, won't have any RF energy going out anyway.
And if there was RF, the IRF510's powered at 12v would be fine (at least for awhile) with the high SWR.

I'd recommend you follow the WireUp instructions as originally written up.
Follow the example in the photo, and do not plug in the Raduino.
I don't see anything wrong with that.
If it were a problem, then we would probably have lots of failures when
blowing new firmware with the rig powered on, no reports of such failures.

I'm much more concerned with the false sense of protection from reversed supply leads 
provided by the recommended reverse diode and no inline fuse, that's a recipe for disaster.
We have several threads on this, search for "reverse polarity" here:  https://groups.io/g/BITX20/messages

Jerry, KE7ER 



On Sat, Jul 14, 2018 at 08:51 AM, Don - KM4UDX wrote:
Hum.....the build instructions say NOTHING about plugging in the raduino BEFORE the current test.  So I didn't plug the board in -- and did the test per instruction. 

If if this is an important caution, why not just say..."plug in raduino then do test".  Why leave us to guess and be stupid? 

So so I was stupid. 

hirosmb <hirosmb@...>
 

Jerry,

Very much appreciated for your detailed explanations.

// hiro, JJ1FXF



2018/07/15 3:18、Jerry Gaffke via Groups.Io <jgaffke@...>のメール:

Not stupid.

It's not in the instructions.
Also, the photo clearly shows no Raduino plugged in.
    http://www.hfsignals.com/index.php/ubitx-wire-up/
Seems Farhan wrote that 7 months ago, and this has all since slipped his mind.

There's nothing that would be damaged if a uBitx main board were powered up
without a Raduino plugged in.  

Looking at the Raduino connector on the uBitx main board schematic near the bottom of this webpage:
    http://www.hfsignals.com/index.php/ubitx-circuit-description/
there are signals for  T/R, TXA,TXB,TXC, CLK0,CLK1,CLK2, CW-KEY, and CW-TONE.


The relay driver at Q15 for T/R won't have any current going into the base,
so that transistor won't be on.  The rig will not be trying to transmit.

Likewise for the LPF band-switching relays at TXA,TXB,TXC.
Though if some of them were on we don't really care.

Perfectly fine that the three clocks are dead, that won't hurt anything.

CW-KEY won't be unbalancing the first mixer because there's no current going in there.
Doesn't really matter anyways because T/R does not have us in transmit mode.

CW-TONE is fine if there's no current going in. 
And would be fine if 5v was applied there anyways.

You might think we could have damage if T/R was somehow injecting current
into Q15, which would power up the transmit amp with inappropriate LPF filters selected by the relays.
However, with all clocks dead, won't have any RF energy going out anyway.
And if there was RF, the IRF510's powered at 12v would be fine (at least for awhile) with the high SWR.

I'd recommend you follow the WireUp instructions as originally written up.
Follow the example in the photo, and do not plug in the Raduino.
I don't see anything wrong with that.
If it were a problem, then we would probably have lots of failures when
blowing new firmware with the rig powered on, no reports of such failures.

I'm much more concerned with the false sense of protection from reversed supply leads 
provided by the recommended reverse diode and no inline fuse, that's a recipe for disaster.
We have several threads on this, search for "reverse polarity" here:  https://groups.io/g/BITX20/messages

Jerry, KE7ER 



On Sat, Jul 14, 2018 at 08:51 AM, Don - KM4UDX wrote:
Hum.....the build instructions say NOTHING about plugging in the raduino BEFORE the current test.  So I didn't plug the board in -- and did the test per instruction. 

If if this is an important caution, why not just say..."plug in raduino then do test".  Why leave us to guess and be stupid? 

So so I was stupid. 

Don - KM4UDX
 

Jerry - as the original "not stupid" guy, thank you VERY much for the detailed analysis of a mainboard w/o raduino.  

This is kit has been so much fun to build. I've loved every minute of it. 

The receiver and audio are really fine. I'm using an efficient clossed-back 5" midrange, and the CEC software.  On a strong signal, the volume is "sweet" and ample. Nice to listen to.  Weak signals & inefficient speaker could easily be a problem. But not here. 

Amazingly the basic cat control (freq change) works great from WSJTX!!  I jumped out of my seat when I clicked on a freq within WSJTX and the uBitx changes to that freq.  How cool is that!!!  And for us liberal arts majors, that means we figured out how to load up the required apps, get the configurations and ports and a thousand other technical details right, and not screw it up. A slap on the back for a non-EE. Hahahah.

The transmit half is not working yet.  I built the mic in a pill bottle in honor of the Dr.  But, there is not enough audio modulation to make a signal.  So I'm using the keyer generated tone, but even that gives me next to no RF output.  So I have to keep working at that.  I'll double check my work and see if I can stumble on the problem and careen into a fix. That normally my problem solving methodology. 

More work to come, with crossed fingers.  I can't tell you all how much I want to make a contact with a transceiver I build. 

Thanks.