Date   

Re: DDS Module is not functioning

William Kimber
 

Hi,

Jim I think you mean 4.95v

Cheers,
Will

On 12/12/15 13:39, n5ib@... [PHSNA] wrote:
 

Glad it's all working, John. It is a fun and useful tool in the shack.

As Will said - the trimmer is to set the reference voltage for the Arduino's A/D converter.
It normally is set as close to BUT NOT GREATER THAN  5.00 V
The Arduino is not happy seeing a voltage on any pin greater than its own 5 V supply.Other than that there is no real need for precision in setting that trimmer, it'll all come out in the calibration. I usually set mine at 5.95V just in case the Arduino's regulator is running a little low.

Speaking of calibration - yep, early on I didn't really try to calibrate my power meter to an absolute level because I didn't have a reliable reference source. I did calibrate it with a step attenuator so the slope would be correct. And as Will mentioned, many applications are just looking at relative changes over a narrow range of frequency. The slope part of the calibration is actually more important than the intercept, since that allows you to tell where 3 dB points are, etc.

Now that I have a decent sig gen and a better scope, and an M^3 RF calibration source, I have gone back and done a careful calibration on all three PHSNA that I've built. Even built  a decent 20 dB pad so I can check the output of some 500 mW VHF beacon transmitters.

Jim, N5IB






---In PHSNA@..., wrote :

I do have a couple of questions, if one or both of you would be so kind as to answer them.

First,there is an R17 variable resistor on the main board that appears to set a voltage for Aref, pin 30 on the Arduino.  What voltage should  this resistor be set for and what is its function?

Second, I think I remember that Jim said in one of his posts that he had never gotten around to calibrating his power meter because it was not necessary for the way he used the PHSNA.  Is that the case, and what uses did not require calibration?  I am thinking they were probably relative power output readings over a fairly narrow frequency range, resulting for example from measuring a crystal filter response.  If so, I may also delay the calibration procedure.


Re: DDS Module is not functioning

N5IB
 

Glad it's all working, John. It is a fun and useful tool in the shack.

As Will said - the trimmer is to set the reference voltage for the Arduino's A/D converter.
It normally is set as close to BUT NOT GREATER THAN  5.00 V
The Arduino is not happy seeing a voltage on any pin greater than its own 5 V supply.Other than that there is no real need for precision in setting that trimmer, it'll all come out in the calibration. I usually set mine at 5.95V just in case the Arduino's regulator is running a little low.

Speaking of calibration - yep, early on I didn't really try to calibrate my power meter to an absolute level because I didn't have a reliable reference source. I did calibrate it with a step attenuator so the slope would be correct. And as Will mentioned, many applications are just looking at relative changes over a narrow range of frequency. The slope part of the calibration is actually more important than the intercept, since that allows you to tell where 3 dB points are, etc.

Now that I have a decent sig gen and a better scope, and an M^3 RF calibration source, I have gone back and done a careful calibration on all three PHSNA that I've built. Even built  a decent 20 dB pad so I can check the output of some 500 mW VHF beacon transmitters.

Jim, N5IB






---In PHSNA@..., <jpking8@...> wrote :

I do have a couple of questions, if one or both of you would be so kind as to answer them.

First,there is an R17 variable resistor on the main board that appears to set a voltage for Aref, pin 30 on the Arduino.  What voltage should  this resistor be set for and what is its function?

Second, I think I remember that Jim said in one of his posts that he had never gotten around to calibrating his power meter because it was not necessary for the way he used the PHSNA.  Is that the case, and what uses did not require calibration?  I am thinking they were probably relative power output readings over a fairly narrow frequency range, resulting for example from measuring a crystal filter response.  If so, I may also delay the calibration procedure.


Re: DDS Module is not functioning

ad7jt@...
 

Hi John,

Here's a link to a white paper that discusses the topic of calibration:



 73,

Dave Collins - AD7JT



Re: DDS Module is not functioning

William Kimber
 

Hi John,

If I can step in here.

First: The Ared voltage uses separate regulator as it is more stable and less noisy than the Arduino power supply. Set to 5v or slightly below, assuming Arduino powered at 5V..

Second: As you say anything requiring just relative measurements does not require calibration. Things like crystal or hi/low/bandpass filters. Return loss, stage gain/loss.  In fact many of the uses of the PHSNA.

Cheers,
Wil,
ZL1TAO.

On 12/12/15 10:44, jpking8@... [PHSNA] wrote:
 

Jim, Nick:


Thought I would finish off this thread and let you know how things have come out at long last.  The amount of time required is largely due to my very limited shop time, which I hope to improve on next year.

As the main unit sits now, I am consistently getting output from the main board.  It does require a push of the reset button on the screen of Nick's Windows program to get the output started.  I understand that is normal behavior.  RF output is constant in power up to about 7 MHz, then falls at the rate of about 6 dB/octave out to 60 MHz.  This is consistent with the AD9851 frequency range. The fall rate is linear when expressed in dB with no large variations in rate.

In the end, it appears that there were two problems causing the original concern.  The first problem was the requirement for a jumper to  cause serial mode data entry to the AD9851.  The second issue was apparently with a bad solder joint somewhere on the main board.  I resoldered everything so I can't really say where the fault was.

Jim asked at one point if any of the traces had deliberately been cut on the main board.  The answer is no and the two places on the board indicating the possibility of a cut do show continuity.

In any event, it works and I'm now happy.

I do have a couple of questions, if one or both of you would be so kind as to answer them.

First,there is an R17 variable resistor on the main board that appears to set a voltage for Aref, pin 30 on the Arduino.  What voltage should  this resistor be set for and what is its function?

Second, I think I remember that Jim said in one of his posts that he had never gotten around to calibrating his power meter because it was not necessary for the way he used the PHSNA.  Is that the case, and what uses did not require calibration?  I am thinking they were probably relative power output readings over a fairly narrow frequency range, resulting for example from measuring a crystal filter response.  If so, I may also delay the calibration procedure.

Thanks for the help guys.  This is probably the slowest build on record.

John, W5IDA


Re: DDS Module is not functioning

John King
 

Jim, Nick:

Thought I would finish off this thread and let you know how things have come out at long last.  The amount of time required is largely due to my very limited shop time, which I hope to improve on next year.

As the main unit sits now, I am consistently getting output from the main board.  It does require a push of the reset button on the screen of Nick's Windows program to get the output started.  I understand that is normal behavior.  RF output is constant in power up to about 7 MHz, then falls at the rate of about 6 dB/octave out to 60 MHz.  This is consistent with the AD9851 frequency range. The fall rate is linear when expressed in dB with no large variations in rate.

In the end, it appears that there were two problems causing the original concern.  The first problem was the requirement for a jumper to  cause serial mode data entry to the AD9851.  The second issue was apparently with a bad solder joint somewhere on the main board.  I resoldered everything so I can't really say where the fault was.

Jim asked at one point if any of the traces had deliberately been cut on the main board.  The answer is no and the two places on the board indicating the possibility of a cut do show continuity.

In any event, it works and I'm now happy.

I do have a couple of questions, if one or both of you would be so kind as to answer them.

First,there is an R17 variable resistor on the main board that appears to set a voltage for Aref, pin 30 on the Arduino.  What voltage should  this resistor be set for and what is its function?

Second, I think I remember that Jim said in one of his posts that he had never gotten around to calibrating his power meter because it was not necessary for the way he used the PHSNA.  Is that the case, and what uses did not require calibration?  I am thinking they were probably relative power output readings over a fairly narrow frequency range, resulting for example from measuring a crystal filter response.  If so, I may also delay the calibration procedure.

Thanks for the help guys.  This is probably the slowest build on record.

John, W5IDA


Re: Problem compiling PHSNA_VB.ino

Jim Smith <jimandmargery@...>
 

Nick, 

Re(re)downloaded the files from Windows PHSNA folder, and this time no '#include Tone.h', and it compiled fine.  Don't understand what happened there. 

Thanks again. 

73

Jim - G3ZQC

On 11 December 2015 at 17:08, Nick Kennedy kennnick@... [PHSNA] <PHSNA@...> wrote:
 

Jim,

I downloaded the latest from the Yahoo group to make sure we are looking at the same files.  It looks like you have the wrong version of Morse.ino.  Based on what you said, I just checked the one I just got from the group and it does not have an include for tone.h and it does have morse_setup().

You should find the two files in the Windows PHSNA folder of the group.

73-

Nick, WA5BDU

On Fri, Dec 11, 2015 at 10:42 AM, Jim Smith jimandmargery@... [PHSNA] <PHSNA@...> wrote:
 

Hi Mike and Nick, 
Thanks for your responses. 
Mike I did a 'find' for the missing variables ignoring case, and didn't find them in morse.ino. 
Nick - the #include Tone.h is commented out in PHSNA_VB.ino, but still there in Morse.ino.  Which is why I added it.  Both ino files are in the same directory.  The variables it seems to be complaining about; morse_rf and morse_spkr are only declared in the conditional assembly - MORSE - which I set to zero.  morse_setup() doesn't exist in my copy of Morse.ino. 

73

Jim - G3ZQC

On 11 December 2015 at 14:41, Nick Kennedy kennnick@... [PHSNA] <PHSNA@...> wrote:
 

Hi Jim,

The tone.h library isn't required because PHSNA doesn't do Morse in audio - it does it in RF by keying the DDS on and off.

It sounds like you may not have the source file Morse.ino in the same folder as PHSNA_VB.ino.  Because that's where the missing functions your errors speak of are located.

73-

Nick, WA5BDU


On Fri, Dec 11, 2015 at 5:06 AM, jimandmargery@... [PHSNA] <PHSNA@...> wrote:
 

Hi, 

I guess this must be operator error(s), but I'm struggling with this. 

Using Arduino 1.6.6 with the .ino files downloaded from Windows PHSNA, rev 1.6 dated March 31.  I read the previous posts on this, the tone.h library has been installed, and appears to have been corrected. 

This is a sample of the errors i get: 

Define MORSE 1

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void setup()':
PHSNA_VB:422: error: 'morse_setup' was not declared in this scope
  morse_setup(); // IF MORSE IS USED
              ^
/home/jim/PHSNA_VB/Morse.ino: At global scope:
Morse:51: error: redefinition of 'unsigned int pitch'
 unsigned int pitch = 600; // local peak for CEM-1201(50)

etc etc..

Define MORSE 0

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void loop()':
PHSNA_VB:456: error: 'morse_rf' was not declared in this scope
  morse_rf = 1; // turn on rf sending
  ^
PHSNA_VB:457: error: 'morse_spkr' was not declared in this scope
  morse_spkr = 0; // turn on audio morse sending

etc...

Same result on my desktop PC running Windows 10, and this laptop running Ubuntu. 

Appreciate any help to straighten me out. 

73

Jim - G3ZQC






Re: Problem compiling PHSNA_VB.ino

Nick Kennedy
 

Jim,

I downloaded the latest from the Yahoo group to make sure we are looking at the same files.  It looks like you have the wrong version of Morse.ino.  Based on what you said, I just checked the one I just got from the group and it does not have an include for tone.h and it does have morse_setup().

You should find the two files in the Windows PHSNA folder of the group.

73-

Nick, WA5BDU

On Fri, Dec 11, 2015 at 10:42 AM, Jim Smith jimandmargery@... [PHSNA] <PHSNA@...> wrote:
 

Hi Mike and Nick, 
Thanks for your responses. 
Mike I did a 'find' for the missing variables ignoring case, and didn't find them in morse.ino. 
Nick - the #include Tone.h is commented out in PHSNA_VB.ino, but still there in Morse.ino.  Which is why I added it.  Both ino files are in the same directory.  The variables it seems to be complaining about; morse_rf and morse_spkr are only declared in the conditional assembly - MORSE - which I set to zero.  morse_setup() doesn't exist in my copy of Morse.ino. 

73

Jim - G3ZQC

On 11 December 2015 at 14:41, Nick Kennedy kennnick@... [PHSNA] <PHSNA@...> wrote:
 

Hi Jim,

The tone.h library isn't required because PHSNA doesn't do Morse in audio - it does it in RF by keying the DDS on and off.

It sounds like you may not have the source file Morse.ino in the same folder as PHSNA_VB.ino.  Because that's where the missing functions your errors speak of are located.

73-

Nick, WA5BDU


On Fri, Dec 11, 2015 at 5:06 AM, jimandmargery@... [PHSNA] <PHSNA@...> wrote:
 

Hi, 

I guess this must be operator error(s), but I'm struggling with this. 

Using Arduino 1.6.6 with the .ino files downloaded from Windows PHSNA, rev 1.6 dated March 31.  I read the previous posts on this, the tone.h library has been installed, and appears to have been corrected. 

This is a sample of the errors i get: 

Define MORSE 1

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void setup()':
PHSNA_VB:422: error: 'morse_setup' was not declared in this scope
  morse_setup(); // IF MORSE IS USED
              ^
/home/jim/PHSNA_VB/Morse.ino: At global scope:
Morse:51: error: redefinition of 'unsigned int pitch'
 unsigned int pitch = 600; // local peak for CEM-1201(50)

etc etc..

Define MORSE 0

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void loop()':
PHSNA_VB:456: error: 'morse_rf' was not declared in this scope
  morse_rf = 1; // turn on rf sending
  ^
PHSNA_VB:457: error: 'morse_spkr' was not declared in this scope
  morse_spkr = 0; // turn on audio morse sending

etc...

Same result on my desktop PC running Windows 10, and this laptop running Ubuntu. 

Appreciate any help to straighten me out. 

73

Jim - G3ZQC





Re: Problem compiling PHSNA_VB.ino

Jim Smith <jimandmargery@...>
 

Hi Mike and Nick, 
Thanks for your responses. 
Mike I did a 'find' for the missing variables ignoring case, and didn't find them in morse.ino. 
Nick - the #include Tone.h is commented out in PHSNA_VB.ino, but still there in Morse.ino.  Which is why I added it.  Both ino files are in the same directory.  The variables it seems to be complaining about; morse_rf and morse_spkr are only declared in the conditional assembly - MORSE - which I set to zero.  morse_setup() doesn't exist in my copy of Morse.ino. 

73

Jim - G3ZQC

On 11 December 2015 at 14:41, Nick Kennedy kennnick@... [PHSNA] <PHSNA@...> wrote:
 

Hi Jim,

The tone.h library isn't required because PHSNA doesn't do Morse in audio - it does it in RF by keying the DDS on and off.

It sounds like you may not have the source file Morse.ino in the same folder as PHSNA_VB.ino.  Because that's where the missing functions your errors speak of are located.

73-

Nick, WA5BDU


On Fri, Dec 11, 2015 at 5:06 AM, jimandmargery@... [PHSNA] <PHSNA@...> wrote:
 

Hi, 

I guess this must be operator error(s), but I'm struggling with this. 

Using Arduino 1.6.6 with the .ino files downloaded from Windows PHSNA, rev 1.6 dated March 31.  I read the previous posts on this, the tone.h library has been installed, and appears to have been corrected. 

This is a sample of the errors i get: 

Define MORSE 1

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void setup()':
PHSNA_VB:422: error: 'morse_setup' was not declared in this scope
  morse_setup(); // IF MORSE IS USED
              ^
/home/jim/PHSNA_VB/Morse.ino: At global scope:
Morse:51: error: redefinition of 'unsigned int pitch'
 unsigned int pitch = 600; // local peak for CEM-1201(50)

etc etc..

Define MORSE 0

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void loop()':
PHSNA_VB:456: error: 'morse_rf' was not declared in this scope
  morse_rf = 1; // turn on rf sending
  ^
PHSNA_VB:457: error: 'morse_spkr' was not declared in this scope
  morse_spkr = 0; // turn on audio morse sending

etc...

Same result on my desktop PC running Windows 10, and this laptop running Ubuntu. 

Appreciate any help to straighten me out. 

73

Jim - G3ZQC




Re: Problem compiling PHSNA_VB.ino

K5ESS
 

Make sure the case of the letters in the variable names match those where the variable is defined.  I’ve forgotten to capitalize some letters and gotten the “ ‘  ‘ was not declared in this scope “ error.  May not be the problem.  Just a suggestion.

Mike K5ESS  

 

From: PHSNA@... [mailto:PHSNA@...]
Sent: Friday, December 11, 2015 5:07 AM
To: PHSNA@...
Subject: [PHSNA] Problem compiling PHSNA_VB.ino

 

 

Hi, 

I guess this must be operator error(s), but I'm struggling with this. 

Using Arduino 1.6.6 with the .ino files downloaded from Windows PHSNA, rev 1.6 dated March 31.  I read the previous posts on this, the tone.h library has been installed, and appears to have been corrected. 

This is a sample of the errors i get: 

Define MORSE 1

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void setup()':
PHSNA_VB:422: error: 'morse_setup' was not declared in this scope
  morse_setup(); // IF MORSE IS USED
              ^
/home/jim/PHSNA_VB/Morse.ino: At global scope:
Morse:51: error: redefinition of 'unsigned int pitch'
 unsigned int pitch = 600; // local peak for CEM-1201(50)

etc etc..

Define MORSE 0

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void loop()':
PHSNA_VB:456: error: 'morse_rf' was not declared in this scope
  morse_rf = 1; // turn on rf sending
  ^
PHSNA_VB:457: error: 'morse_spkr' was not declared in this scope
  morse_spkr = 0; // turn on audio morse sending

etc...

Same result on my desktop PC running Windows 10, and this laptop running Ubuntu. 

Appreciate any help to straighten me out. 

73

Jim - G3ZQC


Re: Problem compiling PHSNA_VB.ino

Nick Kennedy
 

Hi Jim,

The tone.h library isn't required because PHSNA doesn't do Morse in audio - it does it in RF by keying the DDS on and off.

It sounds like you may not have the source file Morse.ino in the same folder as PHSNA_VB.ino.  Because that's where the missing functions your errors speak of are located.

73-

Nick, WA5BDU


On Fri, Dec 11, 2015 at 5:06 AM, jimandmargery@... [PHSNA] <PHSNA@...> wrote:
 

Hi, 

I guess this must be operator error(s), but I'm struggling with this. 

Using Arduino 1.6.6 with the .ino files downloaded from Windows PHSNA, rev 1.6 dated March 31.  I read the previous posts on this, the tone.h library has been installed, and appears to have been corrected. 

This is a sample of the errors i get: 

Define MORSE 1

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void setup()':
PHSNA_VB:422: error: 'morse_setup' was not declared in this scope
  morse_setup(); // IF MORSE IS USED
              ^
/home/jim/PHSNA_VB/Morse.ino: At global scope:
Morse:51: error: redefinition of 'unsigned int pitch'
 unsigned int pitch = 600; // local peak for CEM-1201(50)

etc etc..

Define MORSE 0

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void loop()':
PHSNA_VB:456: error: 'morse_rf' was not declared in this scope
  morse_rf = 1; // turn on rf sending
  ^
PHSNA_VB:457: error: 'morse_spkr' was not declared in this scope
  morse_spkr = 0; // turn on audio morse sending

etc...

Same result on my desktop PC running Windows 10, and this laptop running Ubuntu. 

Appreciate any help to straighten me out. 

73

Jim - G3ZQC



Problem compiling PHSNA_VB.ino

jimandmargery@...
 

Hi, 

I guess this must be operator error(s), but I'm struggling with this. 

Using Arduino 1.6.6 with the .ino files downloaded from Windows PHSNA, rev 1.6 dated March 31.  I read the previous posts on this, the tone.h library has been installed, and appears to have been corrected. 

This is a sample of the errors i get: 

Define MORSE 1

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void setup()':
PHSNA_VB:422: error: 'morse_setup' was not declared in this scope
  morse_setup(); // IF MORSE IS USED
              ^
/home/jim/PHSNA_VB/Morse.ino: At global scope:
Morse:51: error: redefinition of 'unsigned int pitch'
 unsigned int pitch = 600; // local peak for CEM-1201(50)

etc etc..

Define MORSE 0

/home/jim/PHSNA_VB/PHSNA_VB.ino: In function 'void loop()':
PHSNA_VB:456: error: 'morse_rf' was not declared in this scope
  morse_rf = 1; // turn on rf sending
  ^
PHSNA_VB:457: error: 'morse_spkr' was not declared in this scope
  morse_spkr = 0; // turn on audio morse sending

etc...

Same result on my desktop PC running Windows 10, and this laptop running Ubuntu. 

Appreciate any help to straighten me out. 

73

Jim - G3ZQC


Re: Experimenter board pin confusion

Nick Kennedy
 

Thanks Duwayne & Jim.  They're on the boat and headed this way.

73-

Nick, WA5BDU

On Wed, Dec 9, 2015 at 7:43 PM, n5ib@... [PHSNA] <PHSNA@...> wrote:
 

eBay item #

170842982053
Is where I got those pins pictured at "E"

They are round, and are designed to fit the round machined-pin sockets ("B" in the pic). Not the same size pin on opposite sides of the carrier. Note that the longer pins are slightly smaller in diameter. They are the "pins" that mate up with the socket. The other "things sticking out" are soldered into the PCB.

Not really a true double male connector, but can be made to work that way - the fatter pins are a tight fit into a socket. I have soldered wires to them to turn them into "plugs" for off-board connections.

Jim, N5IB



---In PHSNA@..., <kennnick@...> wrote :


I'm going through my junk boxes to see if I have the pins and sockets for this board. Those pins at E are my main confusion.  What they heck are they?  I've searched Mouser and eBay a little and haven't found any that look like that.  Are the pins round?  How come they go both directions like that?  In real life, are they a double-male connector?

I have some of the B sockets.  I think.  I believe they were SIMM or SIPP sockets that folks (like me) were using for HC49U crystal sockets.  Will they accept the pin?  Looks like a standard DIP chip will plug into them, but not a square (or rectangular) pin from a 0.1" header.

73-

Nick, WA5BDU



Re: Experimenter board pin confusion

N5IB
 

eBay item #
170842982053
Is where I got those pins pictured at "E"

They are round, and are designed to fit the round machined-pin sockets ("B" in the pic). Not the same size pin on opposite sides of the carrier. Note that the longer pins are slightly smaller in diameter. They are the "pins" that mate up with the socket. The other "things sticking out" are soldered into the PCB.

Not really a true double male connector, but can be made to work that way - the fatter pins are a tight fit into a socket. I have soldered wires to them to turn them into "plugs" for off-board connections.

Jim, N5IB



---In PHSNA@..., <kennnick@...> wrote :

I'm going through my junk boxes to see if I have the pins and sockets for this board. Those pins at E are my main confusion.  What they heck are they?  I've searched Mouser and eBay a little and haven't found any that look like that.  Are the pins round?  How come they go both directions like that?  In real life, are they a double-male connector?

I have some of the B sockets.  I think.  I believe they were SIMM or SIPP sockets that folks (like me) were using for HC49U crystal sockets.  Will they accept the pin?  Looks like a standard DIP chip will plug into them, but not a square (or rectangular) pin from a 0.1" header.

73-

Nick, WA5BDU


Re: Experimenter board pin confusion

DuWayne Schmidlkofer
 

I bought some of these from eBay.
http://www.ebay.com/itm/10-Pcs-Gold-Plated-2-54mm-Male-40-Pin-Single-Row-Straight-Round-Pin-Header-Strip-/170842982053?hash=item27c70906a5:g:~IwAAOSw-vlVkQOq

But for most projects I just use low profile IC sockets, and mount the standard header pins down from the top.
DuWayne

On 12/9/2015 8:05 PM, Nick Kennedy kennnick@... [PHSNA] wrote:
I'm going through my junk boxes to see if I have the pins and sockets
for this board. Those pins at E are my main confusion. What they heck
are they? I've searched Mouser and eBay a little and haven't found any
that look like that. Are the pins round? How come they go both
directions like that? In real life, are they a double-male connector?

I have some of the B sockets. I think. I believe they were SIMM or
SIPP sockets that folks (like me) were using for HC49U crystal sockets.
Will they accept the pin? Looks like a standard DIP chip will plug into
them, but not a square (or rectangular) pin from a 0.1" header.

73-

Nick, WA5BDU


Experimenter board pin confusion

Nick Kennedy
 

I'm going through my junk boxes to see if I have the pins and sockets for this board. Those pins at E are my main confusion.  What they heck are they?  I've searched Mouser and eBay a little and haven't found any that look like that.  Are the pins round?  How come they go both directions like that?  In real life, are they a double-male connector?

I have some of the B sockets.  I think.  I believe they were SIMM or SIPP sockets that folks (like me) were using for HC49U crystal sockets.  Will they accept the pin?  Looks like a standard DIP chip will plug into them, but not a square (or rectangular) pin from a 0.1" header.

73-

Nick, WA5BDU


Re: PHSNA Type II and Experimentors board T1

N5IB
 

The number of turns is a bit of a trade-off. More turns will be more efficient at low frequencies, but will introduce losses at high frequencies. Fewer turns will not couple well at low frequencies, but are good at the high end.

12 turns seems to be a decent compromise, but I wound mine (in the photo) with 16 because most of my use is fiddling with crystals below 10 MHz.

If you really wanted to use the full 1 to 60 MHz range with an AD-9851 you might need to experiment a bit to see what yields the flattest response. Possibly a high turns count, but on -61 mix ferrite, might be better.

Jim, N5IB




---In PHSNA@..., <k5ess.nothdurft@...> wrote :

Jim,

The schematics and parts list for these call out a 12 turn primary and secondary for T1 although the photo “PHSNA Type II Transformer T1 details” appears to show 16 turns on Pri. And Sec.  Maybe it’s not critical but which is correct/preferred?

Thanks,

Mike K5ESS


PHSNA Type II and Experimentors board T1

K5ESS
 

Jim,

The schematics and parts list for these call out a 12 turn primary and secondary for T1 although the photo “PHSNA Type II Transformer T1 details” appears to show 16 turns on Pri. And Sec.  Maybe it’s not critical but which is correct/preferred?

Thanks,

Mike K5ESS


Re: NPO Capacitor source

Alan McLennan
 

As soon as I posted the above, I knew it was wrong.  I paid only £4.50, which is the buy it now price.  This makes much more sense, and better value.
Cheers
Alan


Re: Can't write to parameters.txt file

Wayne Johnson
 

Gday Jim,
Yes thanks I did get your reply, very much appreciated, and I have confirmed the .txt rename etc but still having trouble.
its early AM here so I will drop you a more detailed off line report once I have COFFEE 😄
Thanks for the reply Jim

73
Wayne


Re: AD9850 DAC output current boost

K5ESS
 

Thanks Jim,

Yes I have the APP Note on using the FET to modulate the DDC output.

 

Mike K5ESS

 

From: PHSNA@... [mailto:PHSNA@...]
Sent: Tuesday, December 08, 2015 2:52 PM
To: PHSNA@...
Subject: [PHSNA] Re: AD9850 DAC output current boost

 

 

I haven't played with R-set. There is a graph in the data sheet showing that the best spurious free dynamic range is at an I-out of 10 mA. Going to 20 mA degrades SFDR by a couple of dB or so. Would only add 5 mA to the average current, so I doubt heating would be an issue. Given the I-supply is around 80 mA, it would be about a 10% increase in dissipation.

Look in the Links area here on the group for an app note about replacing R-set with an FET to amplitude modulate the output (could be the basis of AGC)

Jim, N5IB



---In PHSNA@..., <k5ess.nothdurft@...> wrote :
The AD9850 datasheet says that the max DAC output current is 20mA which can be achieved by reducing the value of the R-SET resistor from 3.9k to 1.95k ohms.  Has anyone tried this and if so were there any deleterious effects?