Simon

As a user of that Arduino sketch for both 4351 and 5355 devices I would be interested to know the changes you have made to update the Lock status

My only fix is to switch the Arduino off then switch on again...... 

Thanks in advance

Dave

G4IDR 

On Mon, 4 Jan 2021, 19:14 G0FCU, <simon@...> wrote:

Robin,

I have no experience of reading SMD component values so looking on Google it seems my R7 (code 74B) is 5.76k ohms and R9 (code 810) is 680R (see attached picture).

Calculating the value of Rset using 5.76k gives a value of Icp of 4.427mA. Reading the datasheet I should set the charge pump current registers to '1101' for Icp=4.38mA.

Having done this I can still get lock from 35 MHz to 4400 MHz and I have corrected a bug in F1CJN's sketch that meant that the lock status was not being updated correctly on the LCD.

73

Simon.

On Mon, 4 Jan 2021 at 16:19, Robin Szemeti - G1YFG <robin@...> wrote:

I just went to the shack to actually check mine ... I was guess at the 5K1 from memory

Mine has 680R for R9 just like the Chinese diagram, I think most of the "normal" software is set up for 1K0 ... it is marked here on the upper row, second one in.

Robin,

I have no experience of reading SMD component values so looking on Google it seems my R7 (code 74B) is 5.76k ohms and R9 (code 810) is 680R (see attached picture).

Calculating the value of Rset using 5.76k gives a value of Icp of 4.427mA. Reading the datasheet I should set the charge pump current registers to '1101' for Icp=4.38mA.

Having done this I can still get lock from 35 MHz to 4400 MHz and I have corrected a bug in F1CJN's sketch that meant that the lock status was not being updated correctly on the LCD.

73

Simon.

On Mon, 4 Jan 2021 at 16:19, Robin Szemeti - G1YFG <robin@...> wrote:

I just went to the shack to actually check mine ... I was guess at the 5K1 from memory

Mine has 680R for R9 just like the Chinese diagram, I think most of the "normal" software is set up for 1K0 ... it is marked here on the upper row, second one in.

I just went to the shack to actually check mine ... I was guess at the 5K1 from memory

Mine has 680R for R9 just like the Chinese diagram, I think most of the "normal" software is set up for 1K0 ... it is marked here on the upper row, second one in.

You may be aware of this already but there is a schematic diagram of the "black" ADF4351 boards. I found it on a Chinese and downloaded it. I have it and the one for the ADF5355 PCB on my website at:
http://gm8bjf.joomla.com/images/pdf/ADF4351.pdf
I found that the topology and component numbering agrees with boards I have. Some of the component values deviate from the diagram. ;-)

73s
Brian GM8BJF.

It's difficult to tell, probably 5.1k. The pin at the bottom of the attached photo is pin 6 of the ADF4351 which seems to be connected to the resistor marked 510 although it is indistinct.

On Sun, 3 Jan 2021 at 23:26, Robin Szemeti - G1YFG <robin@...> wrote:

Glad it is working, out of interest, what value did you find for the charge pump resistor on your board?

On Sun, 3 Jan 2021 at 21:48, G0FCU <simon@...> wrote:

Thanks for your help Robin, all working fine now. I had to amend F1CJN's Arduino sketch to set the charge pump value as you suggested. The recharge pump resistor is not R7 as far as I can work out but could be a seemingly unlabelled resistor next to R3.

Thanks

Simon.

On Sun, 3 Jan 2021 at 08:26, G0FCU <simon@...> wrote:

That's the one. So I need to remove R5 and L1 and thanks for the heads up about the charge pump resistor.

Many thanks

Simon.

G0FCU.

On Sun, 3 Jan 2021, 07:44 Robin Szemeti - G1YFG, <robin@...> wrote:

This one?

https://img.fasttechcdn.com/935/9355700/9355700-7.jpg

R5 is the signal from the onboard xtal

R8 is the signal from the SMA socket

L1 is the power to the onboard xtal

Check also the value of the charge pump resistor and make sure it matches the value set in the software you use to calculate the numbers ... I *think* it is R7 on that board, but please check.  It connects between pins 7 and 20.  Most of the software is set up to expect a value of 1K ... these boards often have 5.1K  in that position ...  if the numbers don't match the software, you'll run out of tuning range.

On Sun, 3 Jan 2021 at 07:14, G0FCU <simon@...> wrote:

Could someone tell me the components that need to be changed on the ADF4351 (black eBay) board to enable a 10 MHz reference input?

I can't find a circuit diagram on-line. Earlier in this thread Andy mentioned an inductor to be removed (L1?) and some other links to be changed.

Thanks
Simon
G0FCU (new to microwaves so bear with me!)

--
Robin Szemeti - G1YFG

--
Robin Szemeti - G1YFG

Glad it is working, out of interest, what value did you find for the charge pump resistor on your board?

On Sun, 3 Jan 2021 at 21:48, G0FCU <simon@...> wrote:

Thanks for your help Robin, all working fine now. I had to amend F1CJN's Arduino sketch to set the charge pump value as you suggested. The recharge pump resistor is not R7 as far as I can work out but could be a seemingly unlabelled resistor next to R3.

Thanks

Simon.

On Sun, 3 Jan 2021 at 08:26, G0FCU <simon@...> wrote:

That's the one. So I need to remove R5 and L1 and thanks for the heads up about the charge pump resistor.

Many thanks

Simon.

G0FCU.

On Sun, 3 Jan 2021, 07:44 Robin Szemeti - G1YFG, <robin@...> wrote:

This one?

https://img.fasttechcdn.com/935/9355700/9355700-7.jpg

R5 is the signal from the onboard xtal

R8 is the signal from the SMA socket

L1 is the power to the onboard xtal

Check also the value of the charge pump resistor and make sure it matches the value set in the software you use to calculate the numbers ... I *think* it is R7 on that board, but please check.  It connects between pins 7 and 20.  Most of the software is set up to expect a value of 1K ... these boards often have 5.1K  in that position ...  if the numbers don't match the software, you'll run out of tuning range.

On Sun, 3 Jan 2021 at 07:14, G0FCU <simon@...> wrote:

Could someone tell me the components that need to be changed on the ADF4351 (black eBay) board to enable a 10 MHz reference input?

I can't find a circuit diagram on-line. Earlier in this thread Andy mentioned an inductor to be removed (L1?) and some other links to be changed.

Thanks
Simon
G0FCU (new to microwaves so bear with me!)

--
Robin Szemeti - G1YFG

--
Robin Szemeti - G1YFG

Thanks for your help Robin, all working fine now. I had to amend F1CJN's Arduino sketch to set the charge pump value as you suggested. The recharge pump resistor is not R7 as far as I can work out but could be a seemingly unlabelled resistor next to R3.

Thanks

Simon.

On Sun, 3 Jan 2021 at 08:26, G0FCU <simon@...> wrote:

That's the one. So I need to remove R5 and L1 and thanks for the heads up about the charge pump resistor.

Many thanks

Simon.

G0FCU.

On Sun, 3 Jan 2021, 07:44 Robin Szemeti - G1YFG, <robin@...> wrote:

This one?

https://img.fasttechcdn.com/935/9355700/9355700-7.jpg

R5 is the signal from the onboard xtal

R8 is the signal from the SMA socket

L1 is the power to the onboard xtal

Check also the value of the charge pump resistor and make sure it matches the value set in the software you use to calculate the numbers ... I *think* it is R7 on that board, but please check.  It connects between pins 7 and 20.  Most of the software is set up to expect a value of 1K ... these boards often have 5.1K  in that position ...  if the numbers don't match the software, you'll run out of tuning range.

On Sun, 3 Jan 2021 at 07:14, G0FCU <simon@...> wrote:

Could someone tell me the components that need to be changed on the ADF4351 (black eBay) board to enable a 10 MHz reference input?

I can't find a circuit diagram on-line. Earlier in this thread Andy mentioned an inductor to be removed (L1?) and some other links to be changed.

Thanks
Simon
G0FCU (new to microwaves so bear with me!)

--
Robin Szemeti - G1YFG

That's the one. So I need to remove R5 and L1 and thanks for the heads up about the charge pump resistor.

Many thanks

Simon.

G0FCU.

On Sun, 3 Jan 2021, 07:44 Robin Szemeti - G1YFG, <robin@...> wrote:

This one?

https://img.fasttechcdn.com/935/9355700/9355700-7.jpg

R5 is the signal from the onboard xtal

R8 is the signal from the SMA socket

L1 is the power to the onboard xtal

Check also the value of the charge pump resistor and make sure it matches the value set in the software you use to calculate the numbers ... I *think* it is R7 on that board, but please check.  It connects between pins 7 and 20.  Most of the software is set up to expect a value of 1K ... these boards often have 5.1K  in that position ...  if the numbers don't match the software, you'll run out of tuning range.

On Sun, 3 Jan 2021 at 07:14, G0FCU <simon@...> wrote:

Could someone tell me the components that need to be changed on the ADF4351 (black eBay) board to enable a 10 MHz reference input?

I can't find a circuit diagram on-line. Earlier in this thread Andy mentioned an inductor to be removed (L1?) and some other links to be changed.

Thanks
Simon
G0FCU (new to microwaves so bear with me!)

--
Robin Szemeti - G1YFG

This one?

https://img.fasttechcdn.com/935/9355700/9355700-7.jpg

R5 is the signal from the onboard xtal

R8 is the signal from the SMA socket

L1 is the power to the onboard xtal

Check also the value of the charge pump resistor and make sure it matches the value set in the software you use to calculate the numbers ... I *think* it is R7 on that board, but please check.  It connects between pins 7 and 20.  Most of the software is set up to expect a value of 1K ... these boards often have 5.1K  in that position ...  if the numbers don't match the software, you'll run out of tuning range.

On Sun, 3 Jan 2021 at 07:14, G0FCU <simon@...> wrote:

Could someone tell me the components that need to be changed on the ADF4351 (black eBay) board to enable a 10 MHz reference input?

I can't find a circuit diagram on-line. Earlier in this thread Andy mentioned an inductor to be removed (L1?) and some other links to be changed.

Thanks
Simon
G0FCU (new to microwaves so bear with me!)

--
Robin Szemeti - G1YFG

Could someone tell me the components that need to be changed on the ADF4351 (black eBay) board to enable a 10 MHz reference input?

I can't find a circuit diagram on-line. Earlier in this thread Andy mentioned an inductor to be removed (L1?) and some other links to be changed.

Thanks
Simon
G0FCU (new to microwaves so bear with me!)

I just took delivery of an ADF5355 synth (against all my principles, from China) and it had the same really poor 25MHz CXO on board.   I tried it, before doing the mod and it was unbelievably off freq - some 1000 ppm.

After converting for external 10MHz source (which is not really optimum frequency for that chip, but does work if you enable the ref-doubler) seems to work fine, but will benefit from the DC supply decoupling mods.

Andy

www.g4jnt.com

On Sat, 26 Dec 2020 at 11:54, Andy Talbot <andy.g4jnt@...> wrote:

You have to remove the L feeding DC to the on board OCXO.   Then move a link or two to get your external input

Andy

www.g4jnt.com

On Sat, 26 Dec 2020 at 11:41, Richard Ferryman via groups.io <g4bbh=btinternet.com@groups.io> wrote:

The main problem I have with this module is that it does not have an input for external 25MHz source.  There is an SMA connctor marked MCLK but this turns out to be an output from the internal (crap) 25MHz reference which is a mile off 25MHz and not very clean..
Otherwise ist seems useable.
Dick

You have to remove the L feeding DC to the on board OCXO.   Then move a link or two to get your external input

Andy

www.g4jnt.com

On Sat, 26 Dec 2020 at 11:41, Richard Ferryman via groups.io <g4bbh=btinternet.com@groups.io> wrote:

The main problem I have with this module is that it does not have an input for external 25MHz source.  There is an SMA connctor marked MCLK but this turns out to be an output from the internal (crap) 25MHz reference which is a mile off 25MHz and not very clean..
Otherwise ist seems useable.
Dick

The main problem I have with this module is that it does not have an input for external 25MHz source.  There is an SMA connctor marked MCLK but this turns out to be an output from the internal (crap) 25MHz reference which is a mile off 25MHz and not very clean..
Otherwise ist seems useable.
Dick

Depends on ref frequency but yes, you're correct, it's not always 'very' small, I should have said 'smaller' however, they're still limited by the on-board controller firmware on some of the boards which have OLED/TFT display and a UI, I'm not sure if you can bypass that with the serial/USB ports though?

On Mon, 23 Nov 2020 at 15:57, Andy G4JNT <andy.g4jnt@...> wrote:

Well, not very small.  Teh ADF4351 has a maximum Denominator register of just 4096, so your minimum step is going to be afew kHz  or so at 10MHz type reference frequencies and OPdiv = 1

If you want REALLY fine step size, use the ADF5355 with a double Fract-N set for mHz resolution   at GHz frequencies

See http://g4jnt.com/ADF5355_Synthesizer_Control.pdf for programming info for that device

Andy

www.g4jnt.com

On Mon, 23 Nov 2020 at 15:39, Clint Sharp <cjaysharp@...> wrote:

Think that's the thing, the ADF4351 chip itself is programmable in very small steps but on the boards with control interface sometimes have a minimum step size enforced in the firmware amd the only way to solve that is to reprogram the MCU

On Mon, 23 Nov 2020, 14:43 Robin Szemeti - G1YFG, <robin@...> wrote:

The chinese modules have the ADF4351 so will have the same steps as any other ADF4351 system ... how you program it is what matters, there are low spur modes, many parameters can affect output quality .. but, in terms of step size, they will behave just like any other ADF4351. I tend to stick to "integer N" modes as the spurs appear to be lower than running in fractional N ... so I pick my references to be an integer division of the output frequency.

On Mon, 23 Nov 2020 at 14:37, Richard Ferryman via groups.io <g4bbh=btinternet.com@groups.io> wrote:

I think it will be useful. Most of my external references are 10MHz which are GPS locked and based on 10MHz double oven.  I now hace a Leo Bodnar GPSDO so I should be able to set up the second output for whatever reference I need whils the output 1 runs 10MHz for my IC-9700.
I have a gut feeling that the Chinese module will have very big frequency steps.
Dick

--
Robin Szemeti - G1YFG

--

Clint. M0UAW IO83

No trees were harmed in the sending of this mail. However, a large number of electrons were greatly inconvenienced.

Well, not very small.  Teh ADF4351 has a maximum Denominator register of just 4096, so your minimum step is going to be afew kHz  or so at 10MHz type reference frequencies and OPdiv = 1

If you want REALLY fine step size, use the ADF5355 with a double Fract-N set for mHz resolution   at GHz frequencies

See http://g4jnt.com/ADF5355_Synthesizer_Control.pdf for programming info for that device

Andy

www.g4jnt.com

On Mon, 23 Nov 2020 at 15:39, Clint Sharp <cjaysharp@...> wrote:

Think that's the thing, the ADF4351 chip itself is programmable in very small steps but on the boards with control interface sometimes have a minimum step size enforced in the firmware amd the only way to solve that is to reprogram the MCU

On Mon, 23 Nov 2020, 14:43 Robin Szemeti - G1YFG, <robin@...> wrote:

The chinese modules have the ADF4351 so will have the same steps as any other ADF4351 system ... how you program it is what matters, there are low spur modes, many parameters can affect output quality .. but, in terms of step size, they will behave just like any other ADF4351. I tend to stick to "integer N" modes as the spurs appear to be lower than running in fractional N ... so I pick my references to be an integer division of the output frequency.

On Mon, 23 Nov 2020 at 14:37, Richard Ferryman via groups.io <g4bbh=btinternet.com@groups.io> wrote:

I think it will be useful. Most of my external references are 10MHz which are GPS locked and based on 10MHz double oven.  I now hace a Leo Bodnar GPSDO so I should be able to set up the second output for whatever reference I need whils the output 1 runs 10MHz for my IC-9700.
I have a gut feeling that the Chinese module will have very big frequency steps.
Dick

--
Robin Szemeti - G1YFG

Think that's the thing, the ADF4351 chip itself is programmable in very small steps but on the boards with control interface sometimes have a minimum step size enforced in the firmware amd the only way to solve that is to reprogram the MCU

On Mon, 23 Nov 2020, 14:43 Robin Szemeti - G1YFG, <robin@...> wrote:

The chinese modules have the ADF4351 so will have the same steps as any other ADF4351 system ... how you program it is what matters, there are low spur modes, many parameters can affect output quality .. but, in terms of step size, they will behave just like any other ADF4351. I tend to stick to "integer N" modes as the spurs appear to be lower than running in fractional N ... so I pick my references to be an integer division of the output frequency.

On Mon, 23 Nov 2020 at 14:37, Richard Ferryman via groups.io <g4bbh=btinternet.com@groups.io> wrote:

I think it will be useful. Most of my external references are 10MHz which are GPS locked and based on 10MHz double oven.  I now hace a Leo Bodnar GPSDO so I should be able to set up the second output for whatever reference I need whils the output 1 runs 10MHz for my IC-9700.
I have a gut feeling that the Chinese module will have very big frequency steps.
Dick

--
Robin Szemeti - G1YFG