I will see if I can improve it, but it's doubtful using those switches. I wont be connecting it to any signal generator, they all have precision attenuators! This was just an exercise and will probably never be used.
@@ptronix I'd use it. Mind you, my sig gen doesn't go down low enough to test receivers without additional attenuation, and fiddling around with fixed attenuators tries my patience.
Nick: you've got to do it all again, and film all the soldering! Just kidding of course, nice work, a fine performer, as expected. 3dB difference at 100 Mhz with all four sections engaged adds up at least, yes? Caught me with the temperature conversion, too, mate, thanks! LOL
Thanks Joe, capacitance of the switch contacts of course at high frequency is significant. The RF would rather go the easy route than 60 db of resistors. I will look at it and see if it can be easily improved.
Very impressed with the result Nick. I’d say as you said up to 100Mhz is perfectly usable with a very good accuracy. If you improve the path with boars that help to keep the 50ohm impedance you can certainly go higher in freq if you need to. I was wondering why if you have precise attenuation with single cells you didn’t get the same precisione adding up cells. It might be the spectrum analyzer. Can you adjust the level of the spectrum analyzer in track gen mode? If not try spot measures with an external gen at higher level, perhaps the function gen that usually can give much higher levels. Well done Nick. My lab is still a mess and waiting for me to put it all together again in the new place. Bye Diego
Hello Diego, I'm going to try to improve it, but the main problem is the switches. The reason for the increasing error when more of the attenuator pads are connected together is I think due to the capacitance of the switch contacts. An RF signal will take the easiest route and rather than go through 60 db of resistors, it will leak through to the shorted switch contacts. The tracking generator was set to its maximum output of 0 dbm. This was only built as an exercise, doubt I'll ever use it! Hope you get your lab together again soon. Best wishes nick
Yes Timothy capacitance issues, may be able to improve it but probably not. Of course I set my standards high. But I've must learn to realise my limitations!
![Oasis - Oasis Live '25 [Official Trailer]](http://i.ytimg.com/vi/gol_JnuEtKM/mqdefault.jpg)
I watched this video and I highly approve of Nick's RF skills. He ain't no Plug & Play Guy.
❣️
Well done Nick. you in your shed again, keep warm my friend 😀
Thanks Mike, I miss the days when it was so hot I had to leave door open!
Nice one Nick. I declare your mojo well and truly restored. 😎
Thanks Bob, mojo temporarily restored!
I think you should be well pleased with that, Nick. Certainly more than usable in reducing the amplitude of your sig gen.
I will see if I can improve it, but it's doubtful using those switches. I wont be connecting it to any signal generator, they all have precision attenuators! This was just an exercise and will probably never be used.
@@ptronix I'd use it. Mind you, my sig gen doesn't go down low enough to test receivers without additional attenuation, and fiddling around with fixed attenuators tries my patience.
Nick: you've got to do it all again, and film all the soldering!
Just kidding of course, nice work, a fine performer, as expected. 3dB difference at 100 Mhz with all four sections engaged adds up at least, yes?
Caught me with the temperature conversion, too, mate, thanks! LOL
Thanks Joe, capacitance of the switch contacts of course at high frequency is significant. The RF would rather go the easy route than 60 db of resistors. I will look at it and see if it can be easily improved.
Very impressed with the result Nick. I’d say as you said up to 100Mhz is perfectly usable with a very good accuracy. If you improve the path with boars that help to keep the 50ohm impedance you can certainly go higher in freq if you need to. I was wondering why if you have precise attenuation with single cells you didn’t get the same precisione adding up cells. It might be the spectrum analyzer. Can you adjust the level of the spectrum analyzer in track gen mode? If not try spot measures with an external gen at higher level, perhaps the function gen that usually can give much higher levels.
Well done Nick.
My lab is still a mess and waiting for me to put it all together again in the new place.
Bye
Diego
Hello Diego, I'm going to try to improve it, but the main problem is the switches.
The reason for the increasing error when more of the attenuator pads are connected together is I think due to the capacitance of the switch contacts. An RF signal will take the easiest route and rather than go through 60 db of resistors, it will leak through to the shorted switch contacts. The tracking generator was set to its maximum output of 0 dbm. This was only built as an exercise, doubt I'll ever use it!
Hope you get your lab together again soon.
Best wishes nick
I think it's very good, but you do set the standard very high! Maybe capacitance effects come into it at the higher end.
Yes Timothy capacitance issues, may be able to improve it but probably not. Of course I set my standards high. But I've must learn to realise my limitations!