Date   
MMIC Amplifier Bias calculation

Alfredo Mendiola Loyola
 

Good Morning,

I'm using this calculator (https://www.changpuak.ch/electronics/mar_era_bias.php) to get the values of
the Capacitors, Resistance and Inductor for my Minicircuits MAV-11BSM amplifier.

The calculator gives me a capacitor value of 68pF and an inductor of 1.6 uH.

What I don't understand is this statement in the calculator:
*******************************************************************
" Make sure the inductance does not saturate at the current of operation "

The calculated current is 60 mA, and the inductance calculated is 1.6uH.
How do I know if the inductor saturates at 60 mA of Current ?


Parameters:
**********
Supply Voltage: 8
Amp Type: MAV-11BSM
Min Freq: 50 Mhz

Output:
*******
R = 41.67 Ohms
L >= 1.592 uH
C >= 0.0637 nf ( 64pF => 68pF) {Usar 0.1uF}
P = 0.15W
I = 60 mA

Re: MMIC Amplifier Bias calculation

Ambro IW2FVO
 

hi Alfredo,
is your si570 working well with the sketch ?
Just to know .
regards,
Ambro
iw2fvo

Re: MMIC Amplifier Bias calculation

Alfredo Mendiola Loyola
 

I'm still designing the schematic before buyinh the components.
RegardsAlfredo Mendiola Loyola

On Friday, May 3, 2019, 9:25:22 AM GMT-5, Ambro IW2FVO <ambrogio.riboli@...> wrote:

hi Alfredo,
is your si570 working well with the sketch ?
Just to know .
regards,
Ambro
iw2fvo

Re: MMIC Amplifier Bias calculation

Nick Kennedy
 

If the inductor has a core material other than air, such as powdered iron
or ferrite (and it probably does), the DC current through it could saturate
the core material. That would cause the inductor to become non-linear or
have much lower than marked inductance.

If you know the manufacturer and part number of the inductor you might be
able to look up what value of current would cause it to saturate. Otherwise
you could wind your own inductor on a toroid and use published values of
its properties to be sure you're avoiding saturation.

73-

Nick, WA5BDU

On Fri, May 3, 2019 at 8:17 AM Alfredo Mendiola Loyola via Groups.Io
<mendiola_loyola=yahoo.com@groups.io> wrote:

Good Morning,

I'm using this calculator (
https://www.changpuak.ch/electronics/mar_era_bias.php) to get the values
of
the Capacitors, Resistance and Inductor for my Minicircuits MAV-11BSM
amplifier.

The calculator gives me a capacitor value of 68pF and an inductor of 1.6
uH.

What I don't understand is this statement in the calculator:
*******************************************************************
" Make sure the inductance does not saturate at the current of operation "

The calculated current is 60 mA, and the inductance calculated is 1.6uH.
How do I know if the inductor saturates at 60 mA of Current ?


Parameters:
**********
Supply Voltage: 8
Amp Type: MAV-11BSM
Min Freq: 50 Mhz

Output:
*******
R = 41.67 Ohms
L >= 1.592 uH
C >= 0.0637 nf ( 64pF => 68pF) {Usar 0.1uF}
P = 0.15W
I = 60 mA



Re: Si570 Set Frequency

Alfredo Mendiola Loyola
 

Ambrogio,

The Arduino Sketch Worked with my si570 Circuit.
I had to use the i2c scanner to find the I2C address of the Si570.

I'm including the picture Links:

https://drive.google.com/open?id=1eaepnqMvr9jU9u9dDs_Uxtw8UiF0xC7R
https://drive.google.com/open?id=1sHBZsVVM_Zjp2s6jpDltEgoaVwspGlh_

The modified source code is in:
https://github.com/oa4ajp/Si570_v5

Thank you for your help.
73
Alfredo Mendiola
OA4AJP

AD9851 Multiplier and Frequency Accuracy

Alfredo Mendiola Loyola
 

Hello,

If I use a TCXO oscillator with a frequency accuracy of 1ppm with an AD9851 which have activated the 6x Multiplier, will the multiplied frequency have the same accuracy of 1ppm?

Example:
Input: TCXO 10 Mhz with 1ppm
Output: AD9851 60 Mhz with X ppm

Will the value of X be 1 ppm ?

Regards
Alfredo
OA4AJP

Re: AD9851 Multiplier and Frequency Accuracy

Clifford Heath
 

Same frequency accuracy because that's locked to your source, but will have
some additional phase noise because that depends on the multiplication
method (the VCO, the phase comparator and the loop filter). The data sheet
will tell you more.


On Mon, 27 May 2019, 04:12 Alfredo Mendiola Loyola via Groups.Io
<mendiola_loyola=yahoo.com@groups.io> wrote:

Hello,

If I use a TCXO oscillator with a frequency accuracy of 1ppm with an
AD9851 which have activated the 6x Multiplier, will the multiplied
frequency have the same accuracy of 1ppm?

Example:
Input: TCXO 10 Mhz with 1ppm
Output: AD9851 60 Mhz with X ppm

Will the value of X be 1 ppm ?

Regards
Alfredo
OA4AJP



Re: AD9851 Multiplier and Frequency Accuracy

Alfredo Mendiola Loyola
 

Thank you for the information Clifford.
Alfredo Mendiola Loyola OA4AJP

On Sunday, May 26, 2019, 5:35:12 PM GMT-5, Clifford Heath <clifford.heath@...> wrote:

Same frequency accuracy because that's locked to your source, but will have
some additional phase noise because that depends on the multiplication
method (the VCO, the phase comparator and the loop filter). The data sheet
will tell you more.


On Mon, 27 May 2019, 04:12 Alfredo Mendiola Loyola via Groups.Io
<mendiola_loyola=yahoo.com@groups.io> wrote:

Hello,

If I use a TCXO oscillator with a frequency accuracy of 1ppm with an
AD9851 which have activated the 6x Multiplier, will the multiplied
frequency have the same accuracy of 1ppm?

Example:
Input: TCXO 10 Mhz with 1ppm
Output: AD9851 60 Mhz with X ppm

Will the value of X be 1 ppm ?

Regards
Alfredo
OA4AJP



WB6OGD Local and Sweep Version

tanveerriaz70pk
 

hi
wich win software i use for your code for si5351?
if you made a software pls up load.
thanks

Re: WB6OGD Local and Sweep Version

wb6ogd
 

Everything is already uploaded.
Look in the Files section for folder:
WB6OGD Local and Sweep Version WithSi5351

https://groups.io/g/PHSNA/files/WB6OGD%20Local%20and%20Sweep%20Version/WithSi5351

See the ReadMe file. The version with the si5351 has excess code, may require some experimentation
and edits, though it does work for me. It includes an antenna analyzer that doesn't work correctly,
SDR 4xfrequency, etc.

Note: this code is not supported by this group, only by me!
On the PC side, you just use Nick's supported code but possibly the older versions?
You can of course run it standalone but things like LCD address, etc might need edits.
Let me know if you need help,
73,
Gary
WB6OGD

Re: Power Meter

Joerg - exDB2OO
 

There is a very nice power calibrator design available from a German ham. Just google for "dl7av calibration". Use a translator, to translate the German text. It creates a 0 dBm sine output. I built it myself (cost approx. 10 EUR) and the harmonics are >30 dB suppressed.

Re: Power Meter

Hans Summers
 

Hi JoergU

There is a very nice power calibrator design available from a German ham.
Just google for "dl7av calibration". Use a translator, to translate the
German text.
It creates a 0 dBm sine output. I built it myself (cost approx. 10 EUR)
and the
harmonics are >30 dB suppressed.
Many thanks for this. Very rare for this to happen, but it happened to be
exactly WHAT I needed and WHEN I needed it... so I googled DL7AV
calibration and found several pages, of which the main one I followed was
http://dl6gl.de/station/selbstregelnder-kurzwellen-kalibrierungsgenerator

So I built my own version from entirely junkbox parts yesterday afternoon
and I have made a YouTube video about it see https://youtu.be/732ESoul088

This will be very useful in my case - thanks again!

73 Hans G0UPL
http://qrp-labs.com

Re: Power Meter

Alfredo Mendiola Loyola
 

I will try it LAter, I have bought a power meter LadyBug LB478.
RegardsAlfredo Mendiola Loyola

On Thursday, September 12, 2019, 07:46:20 AM GMT-5, Hans Summers <hans.summers@...> wrote:

Hi JoergU

There is a very nice power calibrator design available from a German ham.
Just google for "dl7av calibration". Use a translator, to translate the
German text.
It creates a 0 dBm sine output. I built it myself (cost approx. 10 EUR)
and the
harmonics are >30 dB suppressed.
Many thanks for this. Very rare for this to happen, but it happened to be
exactly WHAT I needed and WHEN I needed it... so I googled DL7AV
calibration and found several pages, of which the main one I followed was
http://dl6gl.de/station/selbstregelnder-kurzwellen-kalibrierungsgenerator

So I built my own version from entirely junkbox parts yesterday afternoon
and I have made a YouTube video about it see https://youtu.be/732ESoul088

This will be very useful in my case - thanks again!

73 Hans G0UPL
http://qrp-labs.com

Re: Power Meter

Nick Kennedy
 

Very nice circuit Hans, and a great video to describe it in detail. I'd be
tempted to try to duplicate it but I've already got several "watches" that
give me a well defined RF level.

73-

Nick, WA5BDU

On Thu, Sep 12, 2019 at 7:46 AM Hans Summers <hans.summers@...> wrote:

Hi JoergU

There is a very nice power calibrator design available from a German ham.
Just google for "dl7av calibration". Use a translator, to translate the
German text.
It creates a 0 dBm sine output. I built it myself (cost approx. 10 EUR)
and the
harmonics are >30 dB suppressed.
Many thanks for this. Very rare for this to happen, but it happened to be
exactly WHAT I needed and WHEN I needed it... so I googled DL7AV
calibration and found several pages, of which the main one I followed was
http://dl6gl.de/station/selbstregelnder-kurzwellen-kalibrierungsgenerator

So I built my own version from entirely junkbox parts yesterday afternoon
and I have made a YouTube video about it see https://youtu.be/732ESoul088

This will be very useful in my case - thanks again!

73 Hans G0UPL
http://qrp-labs.com



Re: Power Meter

Glen Leinweber
 

Hans,
This little item begs its "0dbm" output to be christened with a QSO. Seems its
harmonic content may require a bit more filtering for this use.

I wonder if its -30dBm 2nd harmonic might be useful as an amplitude
calibration signal for 20M as well as its 40M 0dBm output?

Re: Power Meter

Nick Kennedy
 

Well, I did go and try the circuit described in the video. I wanted to see
that feedback circuit work to control output level. I had to fool with some
components to get the loop to control. I was only going to build enough to
see that part in action but wound up adding the LPF and attenuator
eventually.

I cheated on the LPF by using molded chokes instead of toroids. The
performance (using PHSNA, of course) looked decent though. For others
experimenting with this circuit, my changes included:

CA3160 for CA3140
74HC86 for 74AC86
6.2 k for 12 k from MOSFET gate to ground
Added a second diode in series with 5 V to lower the reference voltage to
the op-amp
LPF used molded chokes 1.8, 2.2, 1.8 uH for the LPF
Used a 7.030 crystal
Didn't want to fight with building shielding so I just did the 0 dBm output
My attenuator is a tee, 200 ohms, 27 ohms, 25 ohms
(Attenuator shows 220 ohms to the amplifier and 50 ohms toward the load)

It hit 0 dBm right on the money the first time - I was amazed.

I was intrigued by that integrating capacitor feedback. What's its
function? Is it needed? Well, it seems to work better with than without. I
guess it has a stabilizing effect.

It was interesting that when I'd experiment with lowering supply voltage,
the mosfet drain current would take off going to over 100 mA versus typical
35 mA when voltage went below 7.5 or so.

I could not get the "battery low" LED scheme to work. My LEDs may be too
sensitive, if that's the word for it.

Thanks again Hans for an informative video.

73-

Nick, WA5BDU

On Fri, Sep 13, 2019 at 8:52 AM Nick Kennedy <kennnick@...> wrote:

Very nice circuit Hans, and a great video to describe it in detail. I'd
be tempted to try to duplicate it but I've already got several "watches"
that give me a well defined RF level.

73-

Nick, WA5BDU


On Thu, Sep 12, 2019 at 7:46 AM Hans Summers <hans.summers@...>
wrote:

Hi JoergU

There is a very nice power calibrator design available from a German
ham.
Just google for "dl7av calibration". Use a translator, to translate the
German text.
It creates a 0 dBm sine output. I built it myself (cost approx. 10 EUR)
and the
harmonics are >30 dB suppressed.
Many thanks for this. Very rare for this to happen, but it happened to be
exactly WHAT I needed and WHEN I needed it... so I googled DL7AV
calibration and found several pages, of which the main one I followed was
http://dl6gl.de/station/selbstregelnder-kurzwellen-kalibrierungsgenerator

So I built my own version from entirely junkbox parts yesterday afternoon
and I have made a YouTube video about it see https://youtu.be/732ESoul088

This will be very useful in my case - thanks again!

73 Hans G0UPL
http://qrp-labs.com



OT: Yahoo Groups is going away

Terry VK5TM
 

Yahoo Groups is going away.

If you need any files, photo's or other data from any group you are member of, get it now, by the end of December it will all be gone.

Terry VK5TM