Well done for a first project with KiCAD and PCBWay. The BATC boards I have designed are all done with KiCAD, the Winterhill, Knucker, Minitiouner, Refbias etc. You can see my experience progressing if you know what to look for. E.g. Compare the minitiouner and the Knucker or Winterhill. I have done quite a few Nano bards for things like linear amplifiers etc. The 3D view is very useful with the components on and the case to ensure good layout from the build and use point of view.
If you are fine with cutting the dynamic range above 0 dBm and for large powers you would use an attenuator anyway, you can set R7 and R8 on the AD8318 board to increase slope some. I did that with 10k on each to get the slope 2. I also populated C9 to reduce the envelope bandwidth, because the ADC samples slow anyway. Finally I used an ADS1115 ADC board, about as cheap and large as an external reference, but 16 bit (15 above 0 V). The result is surprisingly precise as long as you keep the temperature stable and wait until the AD8318 is heated up (note its power consumption). The datasheet temperature drift is pretty high, so I use a second channel of the ADC to sample the AD8318 temperature, which the board provides as voltage. A few minutes after power up that signal often oscillates for a short time and always only once, like the AD8318 recalibrates something.
Very nice - I've been looking for a DIY meter for a while for my projects. You can buy HP test gear power meters very cheaply but the actual sensor heads are separate and go for $$$$ each
Check if that board has input compensation. For your next update consider a power tap (so that you can use it inline) and a digital attenuator, it comes in handy.
@Tech Minds It looks like you need to debounce the rotary switches 🤔 You can do that in software or hardware. Since this is a small project, I'd just do it in hardware with a capacitor across each switch. Jack Ganssle has some good information on debouncing switches.
That's cool! I've been looking into making a amplifier. But nervous about the voltages and layout! Just something with 10wish of drive and if 600w out... Nothing fancy
Cool project, I'm always interested in power supply or power meter projects. :) Only the autorouters always put also traces just next to each other, 5v and menu signal are unnecessary close to each other, no need for that and it can cause a couple if different problems/challenges. Next time try route your board yourself, will give much better and nicer result.
The commercially made power meters based on similar AD logarithmic converters require the user to enter the frequency because the response of the converter is not constant. How about this one? Also, some power meters do have a frequency counter for this, with or without actually displaying the frequency (what a waste..)
Oh sorry, my fault. It is interesting and a lot to be done here. I was referring to the Nissei power meter that is in almost every shack despite its price. It most probably has a built in frequency counter but doesn't display the result. For your QO-100 amp i guess the best approach is adding a directional coupler of -20 dB and leave it in place during TX. cheers
I just rx "RF363" unit from AliExpress. It is NOT accurate! 😂 At 50 MHz, the reading jumps around. Next to the input connector, there appears to be a 3-way band selector.
10:23 Why did you have to put the attenuator in line friend? By the way, proud Patreon supporter here... If you aren't a supporter ya oughta head on over and help out this esteemed UA-camr. :-)
The reason for the attenuator is because the max input of the meter is around 0dBm, so we add the attenuator between the meter and the radio and then configure the attenuator offset within the menu. Hope that makes sense! Cheeds
mate, that was such a smooth segway into pcbway that i am now a subscriber!
Welcome aboard!
Well done for a first project with KiCAD and PCBWay. The BATC boards I have designed are all done with KiCAD, the Winterhill, Knucker, Minitiouner, Refbias etc. You can see my experience progressing if you know what to look for. E.g. Compare the minitiouner and the Knucker or Winterhill. I have done quite a few Nano bards for things like linear amplifiers etc. The 3D view is very useful with the components on and the case to ensure good layout from the build and use point of view.
Thanks Mike!
Great result Mat, good work!
Cheers!
I admire you for this project. Great job and keep going.!
Thank you!
If you are fine with cutting the dynamic range above 0 dBm and for large powers you would use an attenuator anyway, you can set R7 and R8 on the AD8318 board to increase slope some. I did that with 10k on each to get the slope 2. I also populated C9 to reduce the envelope bandwidth, because the ADC samples slow anyway. Finally I used an ADS1115 ADC board, about as cheap and large as an external reference, but 16 bit (15 above 0 V). The result is surprisingly precise as long as you keep the temperature stable and wait until the AD8318 is heated up (note its power consumption). The datasheet temperature drift is pretty high, so I use a second channel of the ADC to sample the AD8318 temperature, which the board provides as voltage. A few minutes after power up that signal often oscillates for a short time and always only once, like the AD8318 recalibrates something.
Very nice - I've been looking for a DIY meter for a while for my projects. You can buy HP test gear power meters very cheaply but the actual sensor heads are separate and go for $$$$ each
I’ve also been looking at the same devices. The sensors are 4 x the price of the meter! lol thanks
Check if that board has input compensation. For your next update consider a power tap (so that you can use it inline) and a digital attenuator, it comes in handy.
@Tech Minds It looks like you need to debounce the rotary switches 🤔 You can do that in software or hardware. Since this is a small project, I'd just do it in hardware with a capacitor across each switch. Jack Ganssle has some good information on debouncing switches.
That's cool! I've been looking into making a amplifier. But nervous about the voltages and layout! Just something with 10wish of drive and if 600w out... Nothing fancy
Cool project, I'm always interested in power supply or power meter projects. :)
Only the autorouters always put also traces just next to each other, 5v and menu signal are unnecessary close to each other, no need for that and it can cause a couple if different problems/challenges. Next time try route your board yourself, will give much better and nicer result.
Thanks for the info!
For something like this I prefer a nice big analogue meter, changes are then far more obvious than a digital display.
Thank you very much for the review, very interesting design. And what board is used instead of the LM4040C20 ?
a bit of debounce code would fix the knob
Would like to see a DIY swr meter.
Hello, could you send the link to the board on PCBway? Thanks!
Ooh I really like this Matt!! Not a big enough meter for the amp you’re running on qo100 so best sell it to me 🤣 take care mate 73s Gm4zji Chris
I have a solution for the amp, just haven’t fitted it yet. I might do a video on it :)
@@TechMindsOfficial great Matt
The commercially made power meters based on similar AD logarithmic converters require the user to enter the frequency because the response of the converter is not constant. How about this one? Also, some power meters do have a frequency counter for this, with or without actually displaying the frequency (what a waste..)
Did you watch the video? I clearly show band selection.
Oh sorry, my fault. It is interesting and a lot to be done here. I was referring to the Nissei power meter that is in almost every shack despite its price. It most probably has a built in frequency counter but doesn't display the result. For your QO-100 amp i guess the best approach is adding a directional coupler of -20 dB and leave it in place during TX. cheers
I just rx "RF363" unit from AliExpress. It is NOT accurate! 😂
At 50 MHz, the reading jumps around.
Next to the input connector, there appears to be a 3-way band selector.
Can i have the modified code fore thats ad8317
10:23 Why did you have to put the attenuator in line friend?
By the way, proud Patreon supporter here... If you aren't a supporter ya oughta head on over and help out this esteemed UA-camr. :-)
The reason for the attenuator is because the max input of the meter is around 0dBm, so we add the attenuator between the meter and the radio and then configure the attenuator offset within the menu. Hope that makes sense! Cheeds
Sketch i²C ???
doesn't work! The program has an error. If you apply an HF level, the display goes negative. The program inverts the values!
The aliexpress links are broken. VK6ADA