¿ªÔÆÌåÓý

  1. BITX20
  2. Messages
Expanded Topics Messages Polls
Date
Re: Nano on-board regulator...was: I made a mistake

 

There are clearly a few items of ebay electronics about which some fear, uncertainty and doubt is in order.

For example, good luck getting 20 AH at 12v out of this:
? ?

Or getting the maximum rated amps out of any $2 switching (or linear) power supply
across the entire claimed input and output voltage ranges. ?Or even half of the rated amps.
For more than a few milliseconds.

Ebay RD16HHF1 RF power FET's are often some random switcher FET with fresh ink.
That can even happen with the relatively cheap IRF510, why anybody would bother is beyond me.

But many have had surprisingly good luck with the $3 Nano's.
Including most Bitx40 owners.
Though they must be cutting corners where they can off the design of the $30 original.
?
And I did just order 50pcs of the AD8307 for less than I could get two out of Mouser
as per the last paragraph of this post: ?/g/BITX20/message/32675
Got my fingers crossed.

Jerry


On Sun, Oct 22, 2017 at 02:40 pm, Arv Evans wrote:
Regardless of what has been said about the on-board regulator being questionable, it is a pretty
standard 3-terminal regulator it is usually good for at least 100 ma.? I have used a couple dozen
of the Asian manufactured NANO boards with +13.6 volts input and they all worked just fine.??

I suspect that your concern about exceeding current limits may be valid though because there is
no heat sink on those on-board regulators.? Most of my Arduino based test equipment uses the
on-board regulator for NANO and an attached LCD.? Other circuitry is powered from a 7805L or
higher current capable 7805 equivalent.?

There is a lot of not-invented-here and not-manufactured-here sentiment among the ham radio
fraternity.? Some of it justified and some is just myth and FUD (Fear, Uncertainty, and Doubt).
Re: I made a mistake

 

Hi Dale,

I'm hopeful that maybe you got a poorly done batch of clone boards.

I'll do some more testing.

Thanks for your feedback!

73, David KB4FXC

On Sun, 22 Oct 2017, Master Ice wrote:

Nope they didn't survive because the failure of the regulator meant that, when they blew, they went short circuit and slammed full 12V onto the Atmega.
The ones that I have had fail were all fitted with supposedly genuine (ha ha ha ) AMS1117-5 5V versions of the regulator.
Luckily the problem was dealt with by me before the product went to the client by the simple expedient of kludging a better 5V supply and ignoring the Nano regulator completely.
As an aside I puchased a few sacrificial batches of Chinese AMS1117-5 regulators and found that, on test, less than 50% were capable of handling more than 9V input safely.
Some manufacturers claim an input of <=12V while other claim 15V.
The joys of the game.

Dale G4IPZ


----- Original Message -----
From: Dexter N Muir
To: [email protected]
Sent: Sunday, October 22, 2017 9:24 PM
Subject: Re: [BITX20] I made a mistake


Dale me ol' Chin-wah, commiserations - though if the rest of the chip survives you'll have a ready stock of Nanos to hand! That flaky reg is the reason for the Raduino's 78LM7805 regulator - that and the Nano's current drain being either too close to or over the max spec of a 78L05.
p.s. I've taken my 7805 to the other face of the PCB for heatsink clearance and accessibility. It allows me to sit stuff close to that side of the Raduino
Re: Nano on-board regulator...was: I made a mistake

 

Hi Arv,

Thanks for the comments. The Nano's I've got have a (clone, I'm sure)
AM1117-5.0 regulator. I noticed the datasheet says the ABS MAX input
voltage is 15VDC, a stark contrast to 26+ VDC MAX for LM2940 in the
"stock" Nano design, or even the 35VDC limit for 78xx series regulators.

I'll do some additional testing and make sure "LDO" doesn't stand for Low
Dropout OSCILLATOR! HiHI.

73, David KB4FXC

On Sun, 22 Oct 2017, Arv Evans wrote:

David KB4FXC

Regardless of what has been said about the on-board regulator being
questionable, it is a pretty
standard 3-terminal regulator it is usually good for at least 100 ma. I
have used a couple dozen
of the Asian manufactured NANO boards with +13.6 volts input and they all
worked just fine.

I suspect that your concern about exceeding current limits may be valid
though because there is
no heat sink on those on-board regulators. Most of my Arduino based test
equipment uses the
on-board regulator for NANO and an attached LCD. Other circuitry is
powered from a 7805L or
higher current capable 7805 equivalent.

There is a lot of *not-invented-here* and *not-manufactured-here* sentiment
among the ham radio
fraternity. Some of it justified and some is just myth and FUD (Fear,
Uncertainty, and Doubt).

Arv K7HKL
_._


On Sun, Oct 22, 2017 at 3:11 PM, David McGough <kb4fxc@...> wrote:

Hi Dale,

I'm designing a NANO project right now that uses the on-board regulator at
about +12v input. I'm only powering the atmega328p chip and 6 digital
outputs, consisting of low-current LEDs/opto-isolators. I've had no
problems, so far, with a random sampling of about a dozen cheapo
boards....My max current draw is perhaps 25mA. How much current were you
drawing from the regulator where it popped??

....Now I'm concerned that I may need to consider an external regulator.

Thanks,

73, David KB4FXC
Re: I made a mistake

Master Ice
 

?
Nope they didn't survive because the failure of the regulator?meant that, when they blew, they went short circuit and slammed full 12V onto the Atmega.
The ones that I have had fail were all fitted with supposedly genuine (ha ha ha )?AMS1117-5 5V versions of the regulator.
Luckily the problem was dealt with by me before the product went to the client by the simple expedient of kludging a better 5V supply and ignoring the Nano?regulator completely.
As an aside I puchased a few sacrificial?batches of Chinese AMS1117-5 regulators and found that, on test, less than 50% were capable of handling more than 9V input safely.
Some manufacturers claim an input of <=12V while other claim 15V.
The joys of the game.
?
Dale G4IPZ
?
?
----- Original Message -----
Sent: Sunday, October 22, 2017 9:24 PM
Subject: Re: [BITX20] I made a mistake

Dale me ol' Chin-wah, commiserations - though if the rest of the chip survives you'll have a ready stock? of Nanos to hand! That flaky reg is the reason for the Raduino's 78LM7805 regulator - that and the Nano's current drain being either too close to or over the max spec of a 78L05.
p.s. I've taken my 7805 to the other face of the PCB for heatsink clearance and accessibility. It allows me to sit stuff close to that side of the Raduino

Virus-free.

Re: Nano on-board regulator...was: I made a mistake

 

David KB4FXC

Regardless of what has been said about the on-board regulator being questionable, it is a pretty
standard 3-terminal regulator it is usually good for at least 100 ma.? I have used a couple dozen
of the Asian manufactured NANO boards with +13.6 volts input and they all worked just fine.??

I suspect that your concern about exceeding current limits may be valid though because there is
no heat sink on those on-board regulators.? Most of my Arduino based test equipment uses the
on-board regulator for NANO and an attached LCD.? Other circuitry is powered from a 7805L or
higher current capable 7805 equivalent.?

There is a lot of not-invented-here and not-manufactured-here sentiment among the ham radio
fraternity.? Some of it justified and some is just myth and FUD (Fear, Uncertainty, and Doubt).

Arv? K7HKL
_._


On Sun, Oct 22, 2017 at 3:11 PM, David McGough <kb4fxc@...> wrote:
Hi Dale,

I'm designing a NANO project right now that uses the on-board regulator at about +12v input. I'm only powering the atmega328p chip and? 6 digital outputs, consisting of low-current LEDs/opto-isolators. I've had no problems, so far, with a random sampling of about a dozen cheapo boards....My max current draw is perhaps 25mA. How much current were you drawing from the regulator where it popped??

....Now I'm concerned that I may need to consider an external regulator.

Thanks,

73, David KB4FXC


Re: Nano on-board regulator...was: I made a mistake

 

On the raduino, the si5351 is sucking as much as 35ma+5.6ma=40.6ma of 3.3v from the Nano assembly
as per table 3 on p5 of ?https://www.silabs.com/documents/public/data-sheets/Si5351-B.pdf
That 3.3v comes from a regulator tucked inside the USB chip at U2, whatever the clones are stuffing there.
? ??
That's a very significant extra load on U2.

The USB chip at U2 is powered from the Nano's 5v rail which could come from 12v vin through the
dinky 5v regulator at U3, though on the Raduino we instead have a separate 5v LM7805 in a TO220. ?
The Raduino's TO220 can get quite hot.
The Raduino would likely blow U3 if it didn't have a separate TO220 LM7805,
even if U3 was an honest ua78m05 in the sot223

Unless shaving pennies, I'd tend to just feed the Nano 5v and not borrow any 3.3v from it.
Especially if getting pot-luck Nano clones from Ebay.


On Sun, Oct 22, 2017 at 02:11 pm, David McGough wrote:
I'm designing a NANO project right now that uses the on-board regulator at about +12v input. I'm only powering the atmega328p chip and? 6 digital outputs, consisting of low-current LEDs/opto-isolators. I've had no problems, so far, with a random sampling of about a dozen cheapo boards....My max current draw is perhaps 25mA. How much current were you drawing from the regulator where it popped??

....Now I'm concerned that I may need to consider an external regulator.
Re: Nano on-board regulator...was: I made a mistake

 

Hi Dale,

I'm designing a NANO project right now that uses the on-board regulator at about +12v input. I'm only powering the atmega328p chip and? 6 digital outputs, consisting of low-current LEDs/opto-isolators. I've had no problems, so far, with a random sampling of about a dozen cheapo boards....My max current draw is perhaps 25mA. How much current were you drawing from the regulator where it popped??

....Now I'm concerned that I may need to consider an external regulator.

Thanks,

73, David KB4FXC
Re: I made a mistake

 

Dale me ol' Chin-wah, commiserations - though if the rest of the chip survives you'll have a ready stock? of Nanos to hand! That flaky reg is the reason for the Raduino's 78LM7805 regulator - that and the Nano's current drain being either too close to or over the max spec of a 78L05.
p.s. I've taken my 7805 to the other face of the PCB for heatsink clearance and accessibility. It allows me to sit stuff close to that side of the Raduino
Re: Quantum Indians

Simon Thompson
 

¿ªÔÆÌåÓý

When you come right down to it, radio is math and physics¡­and not much else.

On Oct 22, 2017, at 12:52 PM, Steve Black via Groups.Io <kb1chu@...> wrote:

Theres a couple guys over there who know a little bit about radio too (pun intended). Steve kb1chu
On 10/22/2017 03:41 PM, Simon Thompson wrote:
Thanks for sharing these anecdotes. There are many people in North America who do not know about the contribution of South Asian physicists and mathematicians to our understanding of the universe, and the Bitx group¡¯s sharing of these stories will help to spread awareness.
On Oct 22, 2017, at 4:24 AM, Raj vu2zap <rajendrakumargg@...> wrote:

Thanks for the Video Bill!

In '69 I met Sir Raman and along with Balu Balakrishnan attended many lectures on Radio Astronomy. Mrs. Raman was related
to Balu and she called us over when there was anything "radio" in lectures. We also were allowed to borrow tubes and parts
from their labs.. a great encouragement.

A year of so later he passed away. Sir Raman's son Dr. Radhakrishna became vu3fly and allowed our club to use their halls
etc for lectures and such.

Balu became vu2rvb, went to US did masters and was in National Semi.. got a lot of patents and started his own very
successful company Power Intergrations. They made chips for wall warts that went to sleep when you did not draw power.
Eventually he got the environmentalist of the year in 1999 as I remember. The US govt. I believe mandated all equipment
supplied to them should have this tech in it and the US saves a lot of power due to the chip.

Raj

At 22/10/2017, you wrote:
I met chandrashekhar once
? I had no idea who he was my elmer arun, VU2OZ introduced me to him as 'the astronomer guy'. He sat on the sofa drinking his south indian filter coffee from a steel tumbler, chattering away in tamil. What do i care? It was my time with the AR88 in his shack.
- f

On 21 Oct 2017 9:44 am, "Keith VE7GDH" <ve7gdh@...> wrote:
Bill N2CQR wrote...

> I thought you would all be interested in this
> beautiful video. The Quantum Indians



So, if half of the BITX40 is made of Bosons, does
it mean the other half is made of Fermions? It's
all over my head. I just turn it on and it works.
All the electrons know exactly how they are supposed
to jiggle and when.

Bose, Raman, Saha and their fellow scientists were
very smart cookies. We should probably include
Ramanujan in that group.

"The chief thing is to take some pleasure in your
work."

Ummm... was it Raman or Farhan that said that? hi!

--
73 Keith VE7GDH
st
Re: Quantum Indians

Steve Black
 

¿ªÔÆÌåÓý

Theres a couple guys over there who know a little bit about radio too (pun intended). Steve kb1chu
On 10/22/2017 03:41 PM, Simon Thompson wrote:

Thanks for sharing these anecdotes. There are many people in North America who do not know about the contribution of South Asian physicists and mathematicians to our understanding of the universe, and the Bitx group¡¯s sharing of these stories will help to spread awareness.
On Oct 22, 2017, at 4:24 AM, Raj vu2zap <rajendrakumargg@...> wrote:

Thanks for the Video Bill!

In '69 I met Sir Raman and along with Balu Balakrishnan attended many lectures on Radio Astronomy. Mrs. Raman was related
to Balu and she called us over when there was anything "radio" in lectures. We also were allowed to borrow tubes and parts
from their labs.. a great encouragement.

A year of so later he passed away. Sir Raman's son Dr. Radhakrishna became vu3fly and allowed our club to use their halls
etc for lectures and such.

Balu became vu2rvb, went to US did masters and was in National Semi.. got a lot of patents and started his own very
successful company Power Intergrations. They made chips for wall warts that went to sleep when you did not draw power.
Eventually he got the environmentalist of the year in 1999 as I remember. The US govt. I believe mandated all equipment
supplied to them should have this tech in it and the US saves a lot of power due to the chip.

Raj

At 22/10/2017, you wrote:
I met chandrashekhar once
? I had no idea who he was my elmer arun, VU2OZ introduced me to him as 'the astronomer guy'. He sat on the sofa drinking his south indian filter coffee from a steel tumbler, chattering away in tamil. What do i care? It was my time with the AR88 in his shack.
- f

On 21 Oct 2017 9:44 am, "Keith VE7GDH" <ve7gdh@...> wrote:
Bill N2CQR wrote...

> I thought you would all be interested in this
> beautiful video. The Quantum Indians



So, if half of the BITX40 is made of Bosons, does
it mean the other half is made of Fermions? It's
all over my head. I just turn it on and it works.
All the electrons know exactly how they are supposed
to jiggle and when.

Bose, Raman, Saha and their fellow scientists were
very smart cookies. We should probably include
Ramanujan in that group.

"The chief thing is to take some pleasure in your
work."

Ummm... was it Raman or Farhan that said that? hi!

--
73 Keith VE7GDH
st
Re: Bandpass filter

 

Hi Farhan,

Forgive me if I do not understand- you're speaking just about bandpass filters, correct? Or are you suggesting doing this for both the band pass and the low pass filters??
--
Ryan Flowers W7RLF

?

?<-- Learn how to go digital on the BITX40
Re: Quantum Indians

Simon Thompson
 

¿ªÔÆÌåÓý

Thanks for sharing these anecdotes. There are many people in North America who do not know about the contribution of South Asian physicists and mathematicians to our understanding of the universe, and the Bitx group¡¯s sharing of these stories will help to spread awareness.

On Oct 22, 2017, at 4:24 AM, Raj vu2zap <rajendrakumargg@...> wrote:

Thanks for the Video Bill!

In '69 I met Sir Raman and along with Balu Balakrishnan attended many lectures on Radio Astronomy. Mrs. Raman was related
to Balu and she called us over when there was anything "radio" in lectures. We also were allowed to borrow tubes and parts
from their labs.. a great encouragement.

A year of so later he passed away. Sir Raman's son Dr. Radhakrishna became vu3fly and allowed our club to use their halls
etc for lectures and such.

Balu became vu2rvb, went to US did masters and was in National Semi.. got a lot of patents and started his own very
successful company Power Intergrations. They made chips for wall warts that went to sleep when you did not draw power.
Eventually he got the environmentalist of the year in 1999 as I remember. The US govt. I believe mandated all equipment
supplied to them should have this tech in it and the US saves a lot of power due to the chip.

Raj

At 22/10/2017, you wrote:
I met chandrashekhar once
? I had no idea who he was my elmer arun, VU2OZ introduced me to him as 'the astronomer guy'. He sat on the sofa drinking his south indian filter coffee from a steel tumbler, chattering away in tamil. What do i care? It was my time with the AR88 in his shack.
- f

On 21 Oct 2017 9:44 am, "Keith VE7GDH" <ve7gdh@...> wrote:
Bill N2CQR wrote...

> I thought you would all be interested in this
> beautiful video. The Quantum Indians



So, if half of the BITX40 is made of Bosons, does
it mean the other half is made of Fermions? It's
all over my head. I just turn it on and it works.
All the electrons know exactly how they are supposed
to jiggle and when.

Bose, Raman, Saha and their fellow scientists were
very smart cookies. We should probably include
Ramanujan in that group.

"The chief thing is to take some pleasure in your
work."

Ummm... was it Raman or Farhan that said that? hi!

--
73 Keith VE7GDH
st
Re: Quantum Indians

 

We all stand on the shoulders of giants. So many of our greatest scientists and artists are obscure until after their passing.

A friend, Bill W6FA was a prof @ CalTech when Nobel winner Richard Feynman was hired to lecture at lunchtime on any topic he wished.? What amazing good fortune!

Thanks for sharing that link. I've passed it to others who share my fascination with India - esp Indian food<grin>.? So glad I now know whom to blame for Bosons.

Thanks for all you do for us!
Re: BITX40 PTT Noise

Robert Ogburn
 

?Has anyone tried changing C115 and C122 from 1uF to 100nF??? (C115 for receive pop, C122 for carrier issue?)
Re: I made a mistake

Master Ice
 

?
Certainly forget the Chinese Nano clones working much above 9V despite many sellers saying they're good for 12V and even 15V.
I had several release the magic smoke when running them on 12V as the regulators simply popped their tops before I realised the problem was they all had rubbish regulators.
Either run with 9V maximum or preferably go in with a good known 5V supply into the 5V in connection.
?
Dale G4IPZ
?
----- Original Message -----
Sent: Sunday, October 22, 2017 6:36 PM
Subject: Re: [BITX20] I made a mistake

You're probably right.?

But I would not count on a $2 Nano clone dealing with 12v at vin.
Depends on what regulator these clones have.
Some cheaper regulators may not be good beyond 5v.
And at 12v it will be dissipating a bunch of power,
if the regulator does not incorporate a thermal shutdown mode it will be toast.


On Sat, Oct 21, 2017 at 07:42 pm, K5ESS wrote:

Well that¡¯s not strictly correct.? There is one exception.? Although it¡¯s apparently not connected in the Raduino configuration the Vin pin on the Nano goes to a voltage regulator that can take an input of up to a typical value of 15 v.?

?


Virus-free.

W8TEE B40 real time clock connections #w8tee

 

Jack,
I have the 1.08 version of your code and everything is working great, except the connections for the real time clock module have me stumped. I see the reference to pin 53 in the code, but it seems like the RTC module requires 3 pin connections in addition to Vcc and Gnd. I have the same Keyestudio DS3234 module you have pictured in v.04 of the manual. Am I missing something simple?

73 Loren KA5U
Re: ?Raduino v1.26 (eliminate carrier burst, improved calibration method) released

 

Very cool, Allard!
We all much appreciate the time you are putting into this.
I hope some are contributing a few bucks to the charity you show on your github page.

I'm not convinced that just multiplicative correction will be a win when using v1 firmware,
it all depends on whether it is errors in the bfo crystal or errors in the 25mhz si5351 reference
that predominate. ?Will be interesting to see reports in this forum about how v1.26
has affected calibration accuracy for most users.

However, multiplicative correction will definitely be a big win when we go to Allard's v2 firmware,
which will also drive the bfo from the si5351.
Though there may be issues with crosstalk, as Jean Matthieu points out:
? ??/g/BITX20/message/33741
Using only CLK0 and CLK2, holding CLK1 at ground, should somewhat alleviate the crosstalk.
If some users feel that still isn't good enough, perhaps we could cook up a Raduino with two Si5351 chips,
preferably using the same 25mhz reference to simplify these calibration issues..

Jerry, KE7ER


On Sat, Oct 21, 2017 at 04:09 pm, Allard PE1NWL wrote:
  • For VFO calibration, use multiplicative correction (ppm) for better accuracy over a wide frequency range (tks Jerry KE7ER)
Re: I made a mistake

 

You're probably right.?

But I would not count on a $2 Nano clone dealing with 12v at vin.
Depends on what regulator these clones have.
Some cheaper regulators may not be good beyond 5v.
And at 12v it will be dissipating a bunch of power,
if the regulator does not incorporate a thermal shutdown mode it will be toast.


On Sat, Oct 21, 2017 at 07:42 pm, K5ESS wrote:

Well that¡¯s not strictly correct.? There is one exception.? Although it¡¯s apparently not connected in the Raduino configuration the Vin pin on the Nano goes to a voltage regulator that can take an input of up to a typical value of 15 v.?

?
Re: More questions

 

Allard,

The issue is not with your software. I am using a stripped down version of code that I don't think was even for the Raduino (originally from Ron PA3FAT) that uses a rotary encoder and I borrowed the ideas from your CheckTX routine.? What I discovered was that I was using an old version of NT7S's library that was not recognising the command to turn the clock off. I updated the library and it worked fine for the PTT ON cycle but not for the PTT OFF cycle, where I am still getting a burst.

I duplicated the IF routine in checkTX used for the on cycle for use in the off cycle but that did not work.? I was wondering if the PTT_SENSE voltage was dropping too slowly to get back to a false state before the burst came through so rather than using a Boolean function for PTT_SENSE I changed it to an analogread function and set the thresholds at various levels to experiment, hoping to recognise the RX state sooner. The on cycle worked with the analog version of PTT_SENSE (ie no carrier burst) but the off cycle did not. There is still a burst during the off cycle of the PTT switch.? It's late here and I will have to take this up tomorrow. I am a hack when it comes to coding, its pretty much trial by error so there could be something in my code that is making it too slow.

Thanks to Dave, and you for code only version for getting me this far. The carrier burst (and the speaker pop - solved separately) have bothered me since day one and this is the first thing that has worked.

73

Simon VK3ELH
Re: Quantum Indians

 

Thanks for the Video Bill!

In '69 I met Sir Raman and along with Balu Balakrishnan attended many lectures on Radio Astronomy. Mrs. Raman was related
to Balu and she called us over when there was anything "radio" in lectures. We also were allowed to borrow tubes and parts
from their labs.. a great encouragement.

A year of so later he passed away. Sir Raman's son Dr. Radhakrishna became vu3fly and allowed our club to use their halls
etc for lectures and such.

Balu became vu2rvb, went to US did masters and was in National Semi.. got a lot of patents and started his own very
successful company Power Intergrations. They made chips for wall warts that went to sleep when you did not draw power.
Eventually he got the environmentalist of the year in 1999 as I remember. The US govt. I believe mandated all equipment
supplied to them should have this tech in it and the US saves a lot of power due to the chip.

Raj

At 22/10/2017, you wrote:

I met chandrashekhar once
? I had no idea who he was my elmer arun, VU2OZ introduced me to him as 'the astronomer guy'. He sat on the sofa drinking his south indian filter coffee from a steel tumbler, chattering away in tamil. What do i care? It was my time with the AR88 in his shack.
- f

On 21 Oct 2017 9:44 am, "Keith VE7GDH" <ve7gdh@...> wrote:
Bill N2CQR wrote...

> I thought you would all be interested in this
> beautiful video. The Quantum Indians



So, if half of the BITX40 is made of Bosons, does
it mean the other half is made of Fermions? It's
all over my head. I just turn it on and it works.
All the electrons know exactly how they are supposed
to jiggle and when.

Bose, Raman, Saha and their fellow scientists were
very smart cookies. We should probably include
Ramanujan in that group.

"The chief thing is to take some pleasure in your
work."

Ummm... was it Raman or Farhan that said that? hi!

--
73 Keith VE7GDH
82881 - 82900 of 116681