Date   
Re: Second batch of uBITX shipping? #ubitx

Steve Black
 

Don't forget the Johnson Smith catalog!!!! 1966's extraordinarily awesome smoke bomb supplier . Well they really were not that good but the waiting was the hardest part.....Steve kb1chu


On 01/30/2018 09:54 AM, mrz80 wrote:
On 01/29/2018 07:49 PM, Thomas Noel wrote:
Y'all are all so spoiled.

What's the point of even HAVING an internet connection if you can't fret, rant, and worry things to death? :D

I remember ordering from the back of comic books and cereal boxes and having to wait "allow 6-8 weeks for delivery" for my "Amazing X-Ray Glasses" or "Secret Decoder Ring".

No email, no tracking numbers.  Just endless faith and optimism.

And that was just from Kalamazoo  or Battle Creek Michigan.

If you got it at all you were amazed!

Those WERE the good old days, weren't they? Nowadays it's instant this and priority that and two days from the Asteroid Belt to your doorstep!

6-8 weeks would probably be about right. I ordered mine 12/30. Two weeks ago I was told it would be about three weeks 'til it shipped, which ought to put it on my front porch between 6-8 weeks from when I ordered. :D


Re: IRF510 amplifier failures

Arv Evans
 

I give up!  Maybe this IRF510 failure thing is a non-problem.

Someone recently suggested adding a 1K resistor across the
antenna connection to limit really high SWR situations.  That
sounds interesting.

Arv  K7HKL
_._


On Tue, Jan 30, 2018 at 11:08 AM, Tim Gorman <tgorman2@...> wrote:
Respectfully, current limiting in the final amp is exactly how
high-level plate modulation in an old AM transmitter works. Your audio
amplifier, which is required to generate a significant amount of power,
is transformer coupled into the plate lead of your final amplifier.
This allows the audio to vary the voltage and current in the final
amplifier turning it into a mixer. That's how you get the audio
sidebands plus the carrier that is a high level generated AM signal.

Flat-topping in a linear amplifier is actually nothing more than a form
of current limiting and it too generates spurious responses by making
the amplifier non-linear.

Before you do anything to modulate the current and voltage being fed
into a linear amplifier you should have a two-tone audio generator and
a spectrum analyzer of some kind to monitor your signal.

tim

On Mon, 29 Jan 2018 09:49:00 -0700
"Arv Evans" <arvid.evans@...> wrote:

> Maybe part of the point has been missed at several levels.  The
> proposed current
> limiter is not much different from current limiters in many commercial
> power
> supplies.  It is not active until some current value has been
> reached.  Up to then
> there is no current limiting or "modulation" or "compression".  Yes,
> the in-series
> current sensing resistance does allow an output voltage drop until
> voltage across
> this resistance reaches about 0.65 volts to forward bias the sensing
> transistor.
> If your power supply output is not stiff enough to hold a steady
> voltage this could
> add to the sensing resistance and cause voltage droop and in really
> bad cases
> compression of RF output.
>
> Question...is RF compression all that bad?  It is what most transmit
> ALC circuits
> do.  It would also be possible to make the proposed circuit driven by
> reflected
> power instead of current.  Then we could call it a transmit ALC to
> protect the
> IRF510(s).
>
> It would be fairly simple to add a latching function to the limiter
> design so that it
> totally shuts down output when Imax has been reached.  This is
> possible but would
> then require a RESET button or power cycling to restore power to the
> RF PA stage.
>
> It is also possible to change the proposed design to put the current
> sensing ahead
> of the control MOSFET and make that MOSFET into a voltage control
> circuit. This
> was my initial approach but the component count became just too high
> to be an
> internal modification for transceivers.  It would be more suitable for
> converting
> an unregulated power supply to a regulated one.
>
> For those who are using modified PC power supplies it is possible to
> change the
> current sensing so that the switching regulator would shut down if
> Imax of 2 to 3
> amperes is exceeded.  This approach would require power cycling to
> restore operation.
>
> Problem with using fuses is that they have a short but measurable
> heating period
> before they go open.  When they do open they spark internally for
> another short
> period.  Both the delay and the spark are potential problems for
> circuit components.
> Poly-fuse  or resettable fuse devices are intended to address a
> different issue.
> Some are equivalent of FAST-BLOW fuses, and some are just conventional
> resettable circuit breakers.
>
> Suggestion here is that "
> *if you can come up with something else that is adequate, *
> *please submit a circuit drawing and explanation of how it works*"  We
> could all
> benefit from that.
>
> Arv  K7HKL
> _._
>
>
> On Fri, Jan 26, 2018 at 11:27 AM, Tim Gorman <tgorman2@...> wrote:
>
> > A current "limiter" which modulates the current, i.e. limiting the
> > current no matter the drive level, is like applying an ALC to the
> > exciter. Improper design can result in compression of the signal
> > which can then generate spurious responses in the output.
> >
> > If the current limiter is of a "drop-out" style which requires
> > resetting then this won't happen, it will just shut down the
> > exciter. In that case, however, it doesn't provide much efficiency
> > over a plain old fuse!
> >
> > tim ab0wr
> >
> > On Fri, 26 Jan 2018 05:32:08 -0800
> > "n5ib_2" <n5ib@...> wrote:
> >
> > > One other possibility to consider to protect against overcurrent
> > > situations is to use a current limiting power supply, or add a
> > > current limiter to an existing power supply or battery.
> > >
> > > The current limiter circuit whose link is at this site:
> > > <http://n5ib.net/Index.xht>
> > > will go up to 2.2 amps, and includes a low-dropout voltage
> > > regulator that also provides reverse polarity protection.
> > >
> > > There is a version, in a different package, of that same regulator
> > > chip that has an added "tracking" feature - being able to parallel
> > > multiple chips to increase the available current. Details are on
> > > the datasheet in the document.
> > >
> > > Jim, N5IB
> > >
> > >
> > >
> >
> >
> >
> >
> >





Re: Audio gone on new ubitx

Erik Hokansson
 

Tried another pot ..ran wires from the board..tried head phones...still nothing..not sure what I should check on the audio circuit..

Re: uBITX woes, feeling disheartened. #ubitx

K5ESS
 

The pin numbering on these relays is inconsistent  i.e. reversed in some cases. Either will work OK by taking this into consideration.

Mike

K5ESS

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of David Beal
Sent: Tuesday, January 30, 2018 9:36 AM
To: BITX20@groups.io
Subject: Re: [BITX20] uBITX woes, feeling disheartened.

 

Hi Nick, 

I got the same relay and am equally confused as the pinout for both the original relay (Virtual) and this replacement (Panasonic) appears to be the same (across 1/16 on both pinouts); yet the schematic shows the coil across pin 8/9 per:  https://groups.io/g/BITX20/message/40439

Oddly, the data sheet for this relay which I posted here: https://groups.io/g/BITX20/message/40440  is no longer available.  
Further, this post:  https://groups.io/g/BITX20/message/26983  indicates coil across 1/16 also. 

I'm going to disconnect PA power this weekend and use an ohm meter to trace through the relays per someone else's suggestion.  

Dave


--
Dave Beal
AE6RQ

Re: Audio gone on new ubitx

César EA3IAV
 

Do you still have the lcd working? If so, does the radio work but without sound? 
Maybe the ptt is activated....

Re: Bitx Delivered..YAY!!

Art Howard
 

I ordered mine on the 18th and the way it's looking it's probably not going to be a winter project

On 30 Jan 2018 11:25 am, "F5PCX" <JeDecr@...> wrote:
Mine too : ordered 15-12, it arrived through India Post to day.
73 - Jean F5PCX.

Re: Audio gone on new ubitx

Erik Hokansson
 

LCD is working...completely disconnected the ptt..still nothing...it worked for a short time when did 1st power up...

Re: I did it again.. i plugged the arduino pins on reverse

Jerry Gaffke
 

Cesar

So exactly what are the symptoms you are trying to cure now?
What is it that does not work?

Your first post in this thread says:
    i plugged the pins in tge wrond side. Now the sreen is like this 
    i guess i ruined the arduino nano board a d maybe something else

Exactly what pins did you plug in wrong, and in exactly what way?
Did you rotate the entire Raduino around so the display was facing the inside of the radio?
That would put 12v on some of the Nano pins, which would have blown the Nano.
But now you have replaced the Nano and LM7805, can program the Nano, and the display seems to work.
Perhaps the problem now is that you plug the Raduino into the uBitx and you cannot receive any stations?

If so perhaps the si5351 is also blown.
The si5351 is only $1, but difficult to replace as the package is very small.

I suggest you turn the radio on and listen to the si5351 using a shortwave radio
tuned somewhere between 11.995 and 12.000 mhz.
Put the shortwave antenna very near, but not touching, the si5351.
See if you can hear the BFO, it will be a CW carrier with no modulation.
You should also hear the reference oscillator near 25.000 mhz.

Earlier you reported that "I placed the wire from 3v3 to c1(+ side"
Did that fix anything?
If so, exactly where did you add that wire?
This is one case where a photo might actually help, if you can't describe it completely in words.
Is there any evidence of a burnt trace on the board?
This might help us determine if the si5351 was damaged.

Perhaps buy a new Raduino from HFSignals.
That may fix it, though it it is possible that the original "i plugged the pins in tge wrond side"
blew out some stuff in the rest of the radio as well.

Your best path forward might be to find some other ham in your area
with a scope and a good understanding of how this stuff works to help you.
 
In answer to your question, I doubt it is a blown cap or resistor.
But could be, as I don't really know what you did to damage the radio in the first place.

Best Regards,
Jerry, KE7ER



On Tue, Jan 30, 2018 at 10:35 am, César EA3IAV wrote:
I have checked continuity 
Orange wire and a3 from Nano continuity-> ok
And also
D7 from nano to the right last pin connector to board> ok
also connection from raduino board to main board...

i also grounded the orage wire just in case it was the mic

any hint? Maybe a blown cap? I could test resistors in raduino board were fine

W0EB/W2CTX new I2C software for the uBITX Corrections

Jim Sheldon
 

Due to my fat-fingers, some bad code may have gotten into the original _00R release of our I2C modifications and software. Inadvertent use of the D13 I/O pin caused the radio to go into transmit immediately on power up. We had overlooked the fact that D13 is used on the Arduino Nano to control an on-board LED and needs special treatment to use it as a Digital input.

This has been corrected by moving off of D13 and shifting to D11 and D12 instead of D12 and 13.

To make it easier for everyone, I'm posting an updated zipfile that contains the corrected software and for those of you who have decided to try it, I have also included the required LiquidCrystal_I2C library necessary to get the code to compile properly -- Everything is included in the attached ubitx_I2C_V_1_01R.zip

For some reason my ISP is blocking emails from BITX20@groups.io so any questions please reply directly to @W0EB.

Jim Sheldon, W0EB

7 Pins, 8 Pins, What's a Pin Between Friends?

Arvo W0VRA
 

So I'm piddling away with the µB parts as I work out details for my case and stuff, and I can't get the audio connector on.  After an exhaustive investigation, I resort to counting.

The connectors on the board have eight pins, and the harnesses have seven holes.

I think I can make it work.

Re: Cheap Harbor Freight Case for MBITX

Christopher Miller
 

Quite a few cities have maker spaces now. You can for a nominal donation use all sorts of tools. 

Chris

Re: 7 Pins, 8 Pins, What's a Pin Between Friends?

Jerry Gaffke
 

My first run uBitx came with two 8 pin harnesses, plus a 3 and a 2, appropriately enough.
The Bitx40 had a 5 pin harness, but no 7 pin harness.
Wonder where some 7 pin headers slipped into the mix, perhaps the vendor to hfsignals?

Could be that a bunch of uBitx kits went out with the wrong harness.
If others wind up with 7 pin harnesses in their kit, here's how to deal with it:
Audio 8 pin connector into the uBitx main board can skip the ground at pin 8, plenty of other grounds.
Likewise, the Raduino 8 pin connector could do without A7 at pin 1, which is a "spare" in Farhan's code.
Have to shave off the plastic keying guide on one end of the harness connector,
note that it's a different end to be butchered on the two connectors.



On Tue, Jan 30, 2018 at 11:50 am, Arvo KD9HLC wrote:
So I'm piddling away with the µB parts as I work out details for my case and stuff, and I can't get the audio connector on.  After an exhaustive investigation, I resort to counting.

The connectors on the board have eight pins, and the harnesses have seven holes.

Re: uBitx audio potentiometer question.

Dennis Yancey <bigbluedry@...>
 

How would you expect a 250k audio taper pot work? I have a load of these from guitars and amp repair/build.

Re: uBitx audio potentiometer question.

Jerry Gaffke
 

I suppose you could try a 250k volume control pot, but it may not work very well.
The TDA2822M datasheet claims a minimum input impedance of 100k.
    


On Tue, Jan 30, 2018 at 12:30 pm, Dennis Yancey wrote:
How would you expect a 250k audio taper pot work? I have a load of these from guitars and amp repair/build.

Re: 7 Pins, 8 Pins, What's a Pin Between Friends?

Arvo W0VRA
 

I'm going to keep the colors the same as the wire up diagram, so I'll be using black to A on the encoder on one and black to the speaker ground on the other.  I'll add a violet from a spare for the mic.  The violet is not used on the Raduino socket.

And you make an interesting point, that the numbers from pin numbers 1-8 seem to be backward with respect to the colors.

Re: 7 Pins, 8 Pins, What's a Pin Between Friends?

Jerry Gaffke
 

Good idea to keep the colors consistent,
I had no clue what color scheme was chosen for your 7 pin harnesses.

I'll credit you with the point about colors being backward with respect to pin numbers,
as it hadn't occurred to me.  (For those that don't quite follow, the wire colors would
otherwise agree with the resistor color band code.)



On Tue, Jan 30, 2018 at 12:43 pm, Arvo KD9HLC wrote:
I'm going to keep the colors the same as the wire up diagram

Re: I did it again.. i plugged the arduino pins on reverse

César EA3IAV
 

Don’t worry. I will not make you read anymore. I thought It was clear what I explained. If you don’t understand something you may ask. Not to mention English is not my first language. But it is easier for you to make a compilation of my clumsiness. Radio works and receives but ptt is not working. No relais noise. No swiching.  Somehow despite of all connections seem to be good as i teaces continuity. That wire was the only execption I did to make sure there is a connection between that pins I described.

Re: uBITX woes, feeling disheartened. #ubitx

James Lawrie
 

Hello,

Who is the member of this group that has the bad uBitx with all the relay/other issues? Please contact me about your uBitx. I have a new in the box uBitx I might be will to swap for you damaged one, but I need to know what shape it’s in physically.

After all these posts you seem to be getting nowhere and I hate to see problems like this unresolved, no strings or catch I haven’t built mine and you could use it more than me at the moment.


James Lawrie

On Jan 30, 2018, at 13:18, K5ESS <k5ess.nothdurft@...> wrote:

The pin numbering on these relays is inconsistent  i.e. reversed in some cases. Either will work OK by taking this into consideration.

Mike

K5ESS

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of David Beal
Sent: Tuesday, January 30, 2018 9:36 AM
To: BITX20@groups.io
Subject: Re: [BITX20] uBITX woes, feeling disheartened.

 

Hi Nick, 

I got the same relay and am equally confused as the pinout for both the original relay (Virtual) and this replacement (Panasonic) appears to be the same (across 1/16 on both pinouts); yet the schematic shows the coil across pin 8/9 per:  https://groups.io/g/BITX20/message/40439

Oddly, the data sheet for this relay which I posted here: https://groups.io/g/BITX20/message/40440  is no longer available.  
Further, this post:  https://groups.io/g/BITX20/message/26983  indicates coil across 1/16 also. 

I'm going to disconnect PA power this weekend and use an ohm meter to trace through the relays per someone else's suggestion.  

Dave


--
Dave Beal
AE6RQ

Re: 7 Pins, 8 Pins, What's a Pin Between Friends?

Doug W
 

To add another data point, my first run μBITX came 2 x 8 pin, 1 x 3 pin, 1 x 2 pin harnesses.

By running the pattern backwards does Violet regain her virtue?  (please apply apologies in advance if needed)

Message authorization

kk6gkradio@...
 

Greetings, will you allow me to send messages to the group?  I have a working BITX40 but could use some help in updating the firmware.
Thanks,
John Robertson