Excellent! Use that to follow each step thru the audio with an antenna connected to it. Doesn't matter what it's receiving, even noise will show an ever increasing waveform. Actually noise is preferred in this case.
Vince.
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On 10/01/2017 09:16 PM, Ken Macy wrote: Vince
I do have a scope.
KG6PO
--
Michigan VHF Corp.
|
Re: BITX QSO Night, Sunday, October 1, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Good conditions, but lots of stations.?
Made contact with Willie, W1LY (Rhode Island) and Ken, WI1B (Massachusetts)
Heard WA2FZW(?), N2CQR (VA), WA3O (PA), N8DAH (MI), KA9OOI (IN), N6ORS (WI)
|
I'd definitely try to remember which toroid it was.
My guess is that the insulation on the magnet wire wasn't quite properly removed,
and you have a very flaky solder joint there, waiting to fail again.
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On Sun, Oct 1, 2017 at 06:31 pm, Michael Davis wrote:
re-soldered the connections, (which didn't fix it) then glued the toroid to stabilize it. It's been fine ever since.
|
I too had intermittent receive. I used the very non-technical "tap" method. One of the tiny toroids had a problem either in the winding or the soldered connections. I tapped/wiggled it so that it worked, re-soldered the connections, (which didn't fix it) then glued the toroid to stabilize it. It's been fine ever since. I don't remember which toroid it was. Tap and move each one slightly while listening for signals.
Sent from Mike's iPad WA1MAD
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Re: W8TEE pending software release and port(?)
#w8tee
Put a switch on an I/O pin and use INPUT_PULLUP with pinMode(). When a NO pushbutton is pushed, the line is pulled LOW, which changes its state.
Jack, W8TEE
From: Vince Vielhaber <vev@...>
To: [email protected]
Sent: Sunday, October 1, 2017 7:59 PM
Subject: Re: [BITX20] W8TEE pending software release and port(?) #w8tee
Wait a minnit.? I think I understand what they're so horribly trying to
say.? When input pullup is NOT used, a floating connection is low (or
presumably low).? So in order to get it to do something your sensor has
to pull it high.? When the pullup IS used, your sensor has to pull the
pin low.
Vince.
On 10/01/2017 07:54 PM, Vince Vielhaber wrote:
> As I stated when I put it there, it came from the Arduino docs.
>
> Vince.
>
>
>
> On 10/01/2017 07:38 PM, Allard PE1NWL wrote:
>> On Sun, Oct 1, 2017 at 04:01 pm, Vince Vielhaber wrote:
>>
>>? ? On the digital pins:
>>
>>? ? There are 20K pullup resistors built into the Atmega chip that can
>>? ? be accessed from software. These built-in pullup resistors are
>>? ? accessed by setting the pinMode() as INPUT_PULLUP. This effectively
>>? ? inverts the behavior of the INPUT mode, where HIGH means the sensor
>>? ? is off, and LOW means the sensor is on.
>>
>> This is absolutely INCORRECT.
>> pinMode(xx, INPUT) and pinMode(xx, INPUT_PULLUP) only enable/disable the
>> internal pull up resistors.
>> They DON'T invert the behaviour of the input!
>>
>> 73 Allard PE1NWL
>>
>
--
? Michigan VHF Corp.? ?
? ? ? ? ? ? ? ? ? ? ? ? ?
|
Vince
I do have a scope.
KG6PO
|
Re: BITX QSO Night, Sunday, October 1, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere
I had to yell to get through the noise but just managed to work W1LY with a very minimal exchange.
|
Re: W8TEE pending software release and port(?)
#w8tee
Yes that is what they're probably trying to say.
But the wording is very confusing to programmers without an EE background. Many don't understand the real purpose of pull up resistors.
73 Allard PE1NWL
|
Re: W8TEE pending software release and port(?)
#w8tee
From p66 section 14.11.6 of the datasheet at: ?
" If the input buffer is enabled and the input signal is left floating or have an analog signal level close to VCC/2, the input buffer will use excessive power."
That's typical of CMOS input pins. ?If you leave them floating (no pullup or pulldown resistor, and no signal actively driving it) then the input voltage is undefined. ?And if it happens to be right in the middle somewhere (the transition region) the input cell can't decide and that circuitry can start getting hot. ?Or you might get an oscillation going. ?Some chips will have "keeper" circuits that will tend to hold them in their previous state. ?The ATmega328p doesn't have keepers, but allows us to specify pullups (but not pulldowns) for each individual input pin. ?
Don't leave pins defined as inputs just "floating". ?
Probably won't blow up (at least on this chip) but might have weird things happening.
Why is that "effectively inverts" thing in the Arduino docs?
Cuz it was written by a CS major, not an EE.
Jerry
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On Sun, Oct 1, 2017 at 04:59 pm, Vince Vielhaber wrote:
When input pullup is NOT used, a floating connection is low (or presumably low).
|
Yes, I suspected that might be the case. I think I'll put bypass capacitors on both the keying lines and the function switch and spot switch. It probably doesn't help that I am using a plastic enclosure instead of metal, although the board is mounted on a metal plate. I guess I should check the grounding on everything.
Thanks for all your help
Brent
|
Re: W8TEE pending software release and port(?)
#w8tee
Wait a minnit. I think I understand what they're so horribly trying to say. When input pullup is NOT used, a floating connection is low (or presumably low). So in order to get it to do something your sensor has to pull it high. When the pullup IS used, your sensor has to pull the pin low.
Vince.
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On 10/01/2017 07:54 PM, Vince Vielhaber wrote: As I stated when I put it there, it came from the Arduino docs.
Vince.
On 10/01/2017 07:38 PM, Allard PE1NWL wrote:
On Sun, Oct 1, 2017 at 04:01 pm, Vince Vielhaber wrote:
On the digital pins:
There are 20K pullup resistors built into the Atmega chip that can
be accessed from software. These built-in pullup resistors are
accessed by setting the pinMode() as INPUT_PULLUP. This effectively
inverts the behavior of the INPUT mode, where HIGH means the sensor
is off, and LOW means the sensor is on.
This is absolutely INCORRECT.
pinMode(xx, INPUT) and pinMode(xx, INPUT_PULLUP) only enable/disable the
internal pull up resistors.
They DON'T invert the behaviour of the input!
73 Allard PE1NWL
--
Michigan VHF Corp.
|
Re: W8TEE pending software release and port(?)
#w8tee
As I stated when I put it there, it came from the Arduino docs.
Vince.
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Show quoted text
On 10/01/2017 07:38 PM, Allard PE1NWL wrote: On Sun, Oct 1, 2017 at 04:01 pm, Vince Vielhaber wrote:
On the digital pins:
There are 20K pullup resistors built into the Atmega chip that can
be accessed from software. These built-in pullup resistors are
accessed by setting the pinMode() as INPUT_PULLUP. This effectively
inverts the behavior of the INPUT mode, where HIGH means the sensor
is off, and LOW means the sensor is on.
This is absolutely INCORRECT.
pinMode(xx, INPUT) and pinMode(xx, INPUT_PULLUP) only enable/disable the
internal pull up resistors.
They DON'T invert the behaviour of the input!
73 Allard PE1NWL
--
Michigan VHF Corp.
|
Ah, very nice.
And 6 more bytes! ? They all count!
Regarding pullups, this statement isn't exactly correct, but I think I understand where they are coming from:
"This effectively inverts the behavior of the INPUT mode, where HIGH means the sensor is off, and LOW means the sensor is on."
No, turning on pullups inside the ATmega328p does not effectively invert anything,
doesn't do anything different than adding an external resistor from that pin to 5v.
However, the resting state of that pin is then normally high and software reads a 1,?
software reads a 0 when we activate a switch or telegraph key that shorts the pin to ground.?
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On Sun, Oct 1, 2017 at 04:16 pm, Allard PE1NWL wrote:
Or even better:
//configure the PTT SENSE to use the internal pull-up
pinMode(PTT_SENSE, INPUT_PULLUP);
// check if PTT sense line is installed
PTTsense_installed = !digitalRead(PTT_SENSE);
pinMode(PTT_SENSE, INPUT); //disable the internal pull-up
saves 6 bytes.
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Re: BITX QSO Night, Sunday, October 1, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Exchanged call signs with W1LY, then he disappeared. Worked N2CQR in VA.
Heard WA3O and N8DAH.
I'm still on!
--
John - WA2FZW
|
Re: BITX QSO Night, Sunday, October 1, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Well it looked like a promising night but yet again the grow lights around the corner strike again.....
qso:
W1LY
WA3O
KA9OOI
?
Heard
N2CQR
N6ORS
WI1B
?
Hope the FCC helps me out with the RFI but we will see.
?
?73
? David
|
Re: dc power connection bitx40 confusion
I got mine to work with a DPDT switch.? I have the whole thing powered by a 3-cell li-po battery at 12.6V max, 11.1V nominal.
I found that there was a common ground on the input and output of the boost converter I had - There was no voltage potential across the in and out negative terminals, only the voltage of the positive terminal changed.? I don't know a lot about such converters - You may want to check yours.
All of the following are connected directly to ground on my power connector:
Raduino ground
Board ground
PA ground
Boost converter ground (both input and output)
The positive wire from my power connector went to the switch on the volume control knob, so devices were not powered unless I turned the radio on.
From the volume switch, positive connectors went to the:
Raduino
Board power
one of the center poles on the DPDT switch.
I don't know the numbering conventions for switches, but let's number the pins on the back of my DPDT switch like so:
1? ? ? ? 2
3? ? ? ? 4
5? ? ? ? 6
1 and 2 are shorted together.
3 goes to PA +
4 goes to battery +
5 goes to the +out on the boost converter
6 goes to +in on the boost converter.
In position one, the PA+ and battery+ are directly connected - PA gets 12V.? There is no power to the boost converter at all, so it cannot run and possibly produce RFI
In position 2, the + from the battery is routed through the boost converter, feeding 20V to the PA.
A cooler solution might be to power the PA only through the boost converter and have an external knob control the voltage of the booster - You could dial the power wherever you wanted.? You would probably want to make sure you couldn't turn it up past maybe 24V though - Wouldn't want to fry it!? You would also want to make sure your boost converter was RF quiet first, too.? Mine is pretty good, but does produce a quiet hiss over the speaker.
Hope this helps!
KE0GYC
|
By the way if the volume control is set to the minimum end you will not get anything.? Also if you inject your 0db signal it will be shorted out at minimum setting.
Try setting about half way when you touch the centre pin with either wire or signal.? If you still get nothing but you do with putting on pin 3 of LM386 then the connection between is broken. either internally in the wire insulation,? a? dry joint where the volume control socket fits onto board or dodgy connector.
Also it is not a good idea starting at the A/e connection and working through system.? Start at the output end and work towards the A/e.
Cheers,
Will.
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On 02/10/17 12:09, Vince Vielhaber wrote: Unplug the vol control from the board and see if touching the pin that would connect to the wiper gives you noise.? That isolates the preamp from the circuit.? If you get the noise you used to get, look at the preamp stage.? If not, look at the LM386.
Do you have a scope?
Vince.
On 10/01/2017 06:02 PM, Ken Macy wrote:
On Sun, Oct 1, 2017 at 12:00 pm, Ashhar Farhan wrote:
??? audio preamp might be busted. the LM386 seems to be working (from
??? the test that you performed). check the voltages around the audio
??? preamp's base and collector.
??? if the LM386 gives you noise, does the volume control give you noise
??? too? trace the connectivity from pin 3 of the LM386 to the volume
??? control's middle lug. if the noise ensues when you touch a wire to
??? the middle lug of the volume control, then move to the upper lug
??? (not the one connected to the ground), if that works, then, check at
??? the collector of the audio preamp. essentially, you hve to get to
??? the point beyond with the audio doesn't pick up and you have located
??? the trouble.
Farhan, thanks for replying, thanks for your patience.?? Here are the
responses to your thoughts:
audio preamp might be busted.
/*Uh-Oh!? Q16?
*/
the LM386 seems to be working (from the test that you performed). check
the voltages around the audio preamp's base and collector.
/*base: 0.7v?? collector: 1.6v?? emitter: 0v
*/
if the LM386 gives you noise,
/*just touching pin3 no longer gives noise, injecting a 1KHz audio tone
0dB there does appear out the speaker, the 386 is amplifying
*/
does the volume control give you noise too?
*/just touching middle lug no longer gives noise, injecting a 1KHz audio
tone 0dB there does appear out the speaker/*/, the 386 is amplifying/*/
/*
trace the connectivity from pin 3 of the LM386 to the volume control's
middle lug.
/*there is direct connection
*/
if the noise ensues when you touch a wire to the middle lug of the
volume control,
/*there is no noise touching wire here nor anywhere else
*/
then move to the upper lug (not the one connected to the ground),
/*there is no noise touching wire here nor anywhere else
*/
if that works, then, check at the collector of the audio preamp.
/*no noise there either
*/
essentially, you hve to get to the point beyond with the audio doesn't
pick up and you have located the trouble.
/*I agree, but there is no audio anywhere apparently*/
Given all this, should I attempt to replace Q16, audio pre-amp?
?Watching your troubleshooting video, I ran into immediate fail starting
with touching the back of the BNC antenna connector - silence! Then
silence at each and every point that you highlight.? But yet the
transmitter works!
-KG6PO
|
Re: W8TEE pending software release and port(?)
#w8tee
On Sun, Oct 1, 2017 at 04:01 pm, Vince Vielhaber wrote:
On the digital pins:
There are 20K pullup resistors built into the Atmega chip that can be accessed from software. These built-in pullup resistors are accessed by setting the pinMode() as INPUT_PULLUP. This effectively inverts the behavior of the INPUT mode, where HIGH means the sensor is off, and LOW means the sensor is on.
This is absolutely INCORRECT. pinMode(xx, INPUT) and pinMode(xx, INPUT_PULLUP) only enable/disable the internal pull up resistors. They DON'T invert the behaviour of the input! 73 Allard PE1NWL
|
Or even better:
//configure the PTT SENSE to use the internal pull-up
pinMode(PTT_SENSE, INPUT_PULLUP);
// check if PTT sense line is installed
PTTsense_installed = !digitalRead(PTT_SENSE);
pinMode(PTT_SENSE, INPUT); //disable the internal pull-up
saves 6 bytes.
73 Allard PE1NWL
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On Mon, October 2, 2017 01:06, Allard PE1NWL wrote: Jerry,
now I think of it- I have a much better idea:
at startup, initially enable the pullup at A0 and check if the PTTsense is
installed.
Then disable the pullup, like so:
//configure the PTT SENSE to use the internal pull-up
pinMode(PTT_SENSE, INPUT_PULLUP);
// check if PTT sense line is installed
if (!digitalRead(PTT_SENSE))
PTTsense_installed = true; //yes it's installed
else
PTTsense_installed = false; //no it's not installed
pinMode(PTT_SENSE, INPUT); //disable the internal pull-up
This way we get a nice zero volts on A0 during RX.
73 Allard PE1NWL
On Sun, October 1, 2017 23:46, Allard PE1NWL wrote:
Jerry,
Correct, we need the pullup on A0 for reasons of backward compatibility.
At startup the firmware detects whether or not the PTTsense line is
installed. When the PTTsense is NOT installed, input A0 will be open.
Without a pullup the digital level will be undefined so we won't be able
to reliably detect this condition.
With the pullup resistor enabled, and a 10K resistor in the PTTsense
line,
we typically get 1.25V on A0 during RX, which is well below the
threshold.
You could use a smaller resistor value but it shouldn't be necessary.
BTW, the 1.25V suggests that the internal pullup resistors are about
30K,
which is smaller than I expected (I've always thought they were at least
50K).
73 Allard PE1NWL
On Sun, October 1, 2017 20:01, Jerry Gaffke via Groups.Io wrote:
Allard,
You are writing your firmware in such a way that users need not apply
all
mods.
That might require a pullup or pulldown on A0, in which case it's best
to
ignore my previous post.
If thresholds at A0 become an issue, perhaps the recommended resistor
at
A0 could be reduced from 10k,
Perhaps as low as 1k?
Measurements are probably the best source of information here.
However, from the datasheet:
Figures 33.25 and 33.26 on pages 391 and 392 of ??
??
(
)
show the input threshold with Vcc at 5v to be somewhere between 2.1 and
2.7 volts for a digital input on the ATmega328p
Figure 33.17 on page 387 shows pullup current from a pin at 1.3v to be
around 100uA, so (5-1.3)/0.1mA = 37k
for the typical effective pullup resistance for an ATmega328p digital
input with Vcc at 5v.
Jerry
On Sun, Oct 1, 2017 at 10:39 am, Jerry Gaffke wrote:
Allard,
What you have works well enough.
But on the next rev of firmware, you might remove the pullup from A0.
(As you are likely already planning to do.)
|
Unplug the vol control from the board and see if touching the pin that would connect to the wiper gives you noise. That isolates the preamp from the circuit. If you get the noise you used to get, look at the preamp stage. If not, look at the LM386.
Do you have a scope?
Vince.
toggle quoted message
Show quoted text
On 10/01/2017 06:02 PM, Ken Macy wrote: On Sun, Oct 1, 2017 at 12:00 pm, Ashhar Farhan wrote:
audio preamp might be busted. the LM386 seems to be working (from
the test that you performed). check the voltages around the audio
preamp's base and collector.
if the LM386 gives you noise, does the volume control give you noise
too? trace the connectivity from pin 3 of the LM386 to the volume
control's middle lug. if the noise ensues when you touch a wire to
the middle lug of the volume control, then move to the upper lug
(not the one connected to the ground), if that works, then, check at
the collector of the audio preamp. essentially, you hve to get to
the point beyond with the audio doesn't pick up and you have located
the trouble.
Farhan, thanks for replying, thanks for your patience. Here are the
responses to your thoughts:
audio preamp might be busted.
/*Uh-Oh! Q16?
*/
the LM386 seems to be working (from the test that you performed). check
the voltages around the audio preamp's base and collector.
/*base: 0.7v collector: 1.6v emitter: 0v
*/
if the LM386 gives you noise,
/*just touching pin3 no longer gives noise, injecting a 1KHz audio tone
0dB there does appear out the speaker, the 386 is amplifying
*/
does the volume control give you noise too?
*/just touching middle lug no longer gives noise, injecting a 1KHz audio
tone 0dB there does appear out the speaker/*/, the 386 is amplifying/*/
/*
trace the connectivity from pin 3 of the LM386 to the volume control's
middle lug.
/*there is direct connection
*/
if the noise ensues when you touch a wire to the middle lug of the
volume control,
/*there is no noise touching wire here nor anywhere else
*/
then move to the upper lug (not the one connected to the ground),
/*there is no noise touching wire here nor anywhere else
*/
if that works, then, check at the collector of the audio preamp.
/*no noise there either
*/
essentially, you hve to get to the point beyond with the audio doesn't
pick up and you have located the trouble.
/*I agree, but there is no audio anywhere apparently*/
Given all this, should I attempt to replace Q16, audio pre-amp?
Watching your troubleshooting video, I ran into immediate fail starting
with touching the back of the BNC antenna connector - silence! Then
silence at each and every point that you highlight. But yet the
transmitter works!
-KG6PO
--
Michigan VHF Corp.
|
Allard PE1NWL
Brent Seres/ VE3CUS
N8DAH