Manuel, excellent Not only is this an excellent project for the community, that you touch all basis in your presentation. Document the circuitry given enough information that others can modify into their own requirements. Your 3-D printing skills are well displayed as well in the housing.
This would be more balanced over using a NE555. Yes Elliot is very creative, and has come great circuits. Another 'Premium' EO&N circuit. Well done! 👍 --- Giving out the file to create the case is very kind 💚of you since it takes time to do that! You can also buy Aluminum tape as well for shielding.
@ Well of course it can its an oscillator. I thought you were talking about op amps now I see that you are in fact suggesting that the timer be used to generate an audio tone ! have you missed the point here ? If it was an NE555 circuit that was wanted there would be no video ! "This would be more balanced over using a NE555 " I see what your getting at now LOL! I don't know about age but based on the topic and your comment I have spent my 40 years as an EE far more productively than you Sir....Good Evening.
Great project! Simple and lots of ways to experiment. One thing to try as an experiment is to look at the fft and adjust one of the trimmer pots to see if you can lower the distortion by balancing out the two phase shift circuits.
@@electronicsoldandnew If you have a decent audio input into your computer, they are actually surprisingly capable of doing great FFTs for your signals - in the audio band (for which they were designed for). There's some good nice software around to use them for that. Just make sure not to put any huge voltage into them :D
Very good. Probably my senility showing, but I seem to remember a conventional dial lamp (3:48) is PTC (ergo dim bulb concept), not NTC. Some LED lamps are NTC, allegedly.
I built a device based on the Wien Bridge Bulb Stabilised oscillator as well for same reasons. I stayed original and used a 12v CH731 bulb a OPA1656 op amp and a couple of LIPO batteries from an old Vape to give a dual supply for the op amp I did use good quality for the 2 resistors and 2 capacitors I made a PCB. I fixed the output at 800mV @1Khz and I have THD+N of 0.003% so about 90db down which is fine I think, but might be improved. Also I have used some of Rod's work too !! he is awesome and I pinched bits of his headphone amp design and that sounds epic ! That's a fantastic enclosure. I use my Siglent FFT as well but I measured it with ARTA as well, the scope is on the edge of its abilities right where you are but great video gonna sub you !.....cheers.
véry interesting projet, 18:56 i never thought of printing "face plate" i'm gonna think about for my next projet nice closing enclosure 23:23 there are 9V battery with usb charger, if you had those kind of battery and add a hole for the usb port, you dont even need to open it to change the battery thx for the video
The 9V battery with USB charger, they are usually a lithium rechargeable battery and a tiny switching power supply inside to raise the voltage to 9V. If you want a low noise, low distortion analogue circuit, then stay the hell away from tiny switching power supplies. In this case, unfortunately good ol' alkaline is likely better for operation. It would be better to use a 1S or 2S lipo battery straight up if you wanted to go the rechargeable route.
Potencjometr działa w dobrą stronę. Zobacz, jak są budowane generatory analogowe, np. GW instek GAG-810. Skala częstotliwości nie jest na obudowie, tylko na osi potencjometru. Wtedy wygląda PRO;) Wszystkiego dobrego.
3:44 A (incandescent) lamp is a PTC, not an NTC. 16:35 Mouser sells Inverse Log Potentiometers. 25:10 Look at the loop that your ground makes to connect. It acts like an antenna. Better use BNC cables. Not so important for the frequenties you use there, but when looking for harmonics maybe it differs.
I cheat and use a XR2206, my PCB is on Manuel's sponsors site. Use a 9V battery or a 12V stack of AAAs. Can add a small 8DIP 1W+ amp for checking speakers etc. Makes a great small portable bit of test gear.
While the XR2206 is a nice chip to work with, there is one big problem; EXAR stopped production of this chip long ago. Last order date was April 2011 as per the official EXAR bulletin. And as such are no longer available from big trustworthy suppliers. Yes, the EXAR branded ICs are still widely available on the bay, but lots of people are having problems with them. I too had ordered some XR labelled XR2206CP with datecodes F0919 and F0911 from various chinese suppliers, and all of those showed faults; ranging from to the IC being stuck on the second internal VCO despite an open FSK shift input, to excessive current draw, to totally distorted sine wave. So be cautious buying "XR" labelled XR2206 chips nowadays unless you have a reliable source with NOS stock. There is however one version of this chip I got hands on, which was made by HLF (Shenzhen honglifa Electronics); "XR2206CP HLF A8". Clearly a clone but on spec to the original XR2206 datasheet. So maybe try sourcing those HLF clones instead of getting burned by the original XR branded ones.
There is a better design possible. I will explain: You are after a phase shift. If you take an integrator, you will see that it phase shifts. With two integrations, you can make a two stage low pass filter that has a really high Q. This is not an oscillator but if you could feed in a signal at that frequency, it will clean it up and amplify a lot. In the classic 3 opamp, integrator based filter, one op-amp is not an integrator. It is simply an inverting amplifier. Instead of limiting to control amplitude in an oscillator, a tiny positive feedback makes that amplifier stage cause the system to oscillate. The up side to this method is that you have very little distortion in the resulting signal.
Sure, but as you’ve guessed … where’s the fun in that? 😊 Actually, since we can listen to practically any radio station on the planet using a phone app, why restore tune radios at all? It’s all in the fun of the hobby for me.
@@electronicsoldandnewWell you are right, then again it is a bit of a skewd argumentation. Until now, and probably still in the future, you will be using ur modern signal generator. That is as high tech as using an old phone with an app.- With maybe a opamp buffer on the headphone output for protection. And even using an old phone as audio frequency scope is a valid approach. And about your argumentation on using phone to listen to webradio, why repair old radios; you are lucky to still have AM radio stations. Here AM radio was shut down in 2015. And some northern european countries have even done away with analog FM. So for many of us, it is a must to use webradio reception and rebroadcast it to AM unless you want all AM radios to be shelf queens or just be useable at night.
I don't understand, NTC thermistors are common as all hell and cheap as chips? There's 11 68k thermistors on LCSC at the moment, and 21 50ks, hundreds of 10k and 100ks, etc
You could label that control 'wavelength' rather than 'frequency', then it would increase with clockwise rotation!
True
Awesome :)
Nice project. Greatings from South Africa.
Howzitttt 😊
Lekker 😂@@electronicsoldandnew
😊
Manuel, excellent
Not only is this an excellent project for the community, that you touch all basis in your presentation. Document the circuitry given enough information that others can modify into their own requirements. Your 3-D printing skills are well displayed as well in the housing.
Thank you 🙏
@@electronicsoldandnew Tell us what 3D Printer you are using...
It’s a bambu lab a1 combo
Thanks for sharing your knowledge 🙏🏾
My pleasure
This would be more balanced over using a NE555. Yes Elliot is very creative, and has come great circuits. Another 'Premium' EO&N circuit. Well done! 👍
---
Giving out the file to create the case is very kind 💚of you since it takes time to do that! You can also buy Aluminum tape as well for shielding.
👍
NE555 is a timer! you mean NE5532 and that is a good choice.
@@andymouse - That's true, but it can also run at a particular frequency. You must be too young!
@ Well of course it can its an oscillator. I thought you were talking about op amps now I see that you are in fact suggesting that the timer be used to generate an audio tone ! have you missed the point here ? If it was an NE555 circuit that was wanted there would be no video !
"This would be more balanced over using a NE555 " I see what your getting at now
LOL! I don't know about age but based on the topic and your comment I have spent my 40 years as an EE far more productively than you Sir....Good Evening.
@@andymouse - I;m a retired EE in 2005, now at the age of 76. I know main work with Pi Pico's.
Very nice project! thanks for sharing.
My pleasure
Great project! Simple and lots of ways to experiment. One thing to try as an experiment is to look at the fft and adjust one of the trimmer pots to see if you can lower the distortion by balancing out the two phase shift circuits.
Yes, I’m playing with that now actually 😊 This FFT isn’t very good though.
@@electronicsoldandnew If you have a decent audio input into your computer, they are actually surprisingly capable of doing great FFTs for your signals - in the audio band (for which they were designed for). There's some good nice software around to use them for that. Just make sure not to put any huge voltage into them :D
I’ve used one of those packages before quite successfully.
Very good. Probably my senility showing, but I seem to remember a conventional dial lamp (3:48) is PTC (ergo dim bulb concept), not NTC. Some LED lamps are NTC, allegedly.
True. The lamp would be connected in the lower end of the opamp circuit in a Wien bridge, while the ntc goes on the feedback path.
Regarding the pot direction, Print a small gear box even with reduction if you so wish!
👍
Another solution would have been a fully differential output with blocking capacitors.
But nice project 👍🏻
:)
@andymouse cheese 🧀
@@p_mouse8676 SQUEAK !!!!!!!
@ Squeak ! :)
I built a device based on the Wien Bridge Bulb Stabilised oscillator as well for same reasons. I stayed original and used a 12v CH731 bulb a OPA1656 op amp and a couple of LIPO batteries from an old Vape to give a dual supply for the op amp I did use good quality for the 2 resistors and 2 capacitors I made a PCB. I fixed the output at 800mV @1Khz and I have THD+N of 0.003% so about 90db down which is fine I think, but might be improved. Also I have used some of Rod's work too !! he is awesome and I pinched bits of his headphone amp design and that sounds epic ! That's a fantastic enclosure. I use my Siglent FFT as well but I measured it with ARTA as well, the scope is on the edge of its abilities right where you are but great video gonna sub you !.....cheers.
👍
Clever chap! Well done.
Thanks
@@electronicsoldandnew BTW new caps in the AF board of the FRG 7 have made a HUGE difference! Also bought a new SG and scope.
👍
Perhaps you could use a pair of gears to reverce direction of the pot. Even make it fine tunning. Or a tunning cord.
👍
Great project .
👍
Great! Maybe next project will be an RF Sig-Gen with fixed 10.7Mhz and 455Khz
Not a bad idea, but the 455 must extend to 460, because most of the German sets I work on use that frequency.
thank you sir for the work I downloaded the files but they do not open. what types of files. concerning the diagram by which software did you do it
PDF, and 3d print files
1 idea.
You can reverse the characteristic of the pot with two gears. One should be mounted on the pot, the other on the rotary knob.
👍
véry interesting projet,
18:56 i never thought of printing "face plate" i'm gonna think about for my next projet
nice closing enclosure
23:23 there are 9V battery with usb charger, if you had those kind of battery and add a hole for the usb port, you dont even need to open it to change the battery
thx for the video
👍
The 9V battery with USB charger, they are usually a lithium rechargeable battery and a tiny switching power supply inside to raise the voltage to 9V. If you want a low noise, low distortion analogue circuit, then stay the hell away from tiny switching power supplies. In this case, unfortunately good ol' alkaline is likely better for operation. It would be better to use a 1S or 2S lipo battery straight up if you wanted to go the rechargeable route.
👍 I personally stay away from boost converters precisely because of noise.
Potencjometr działa w dobrą stronę. Zobacz, jak są budowane generatory analogowe, np. GW instek GAG-810. Skala częstotliwości nie jest na obudowie, tylko na osi potencjometru. Wtedy wygląda PRO;) Wszystkiego dobrego.
Thanks
3:44 A (incandescent) lamp is a PTC, not an NTC.
16:35 Mouser sells Inverse Log Potentiometers.
25:10 Look at the loop that your ground makes to connect. It acts like an antenna. Better use BNC cables. Not so important for the frequenties you use there, but when looking for harmonics maybe it differs.
The lamp is used in the base leg of the opamp circuit, while the ntc goes on the feedback path.
@@electronicsoldandnew Sorry, I thought NTC and lamp were both used as NTC, I have not read the article itself.
👍
I cheat and use a XR2206, my PCB is on Manuel's sponsors site. Use a 9V battery or a 12V stack of AAAs. Can add a small 8DIP 1W+ amp for checking speakers etc. Makes a great small portable bit of test gear.
👍
While the XR2206 is a nice chip to work with, there is one big problem; EXAR stopped production of this chip long ago. Last order date was April 2011 as per the official EXAR bulletin. And as such are no longer available from big trustworthy suppliers. Yes, the EXAR branded ICs are still widely available on the bay, but lots of people are having problems with them. I too had ordered some XR labelled XR2206CP with datecodes F0919 and F0911 from various chinese suppliers, and all of those showed faults; ranging from to the IC being stuck on the second internal VCO despite an open FSK shift input, to excessive current draw, to totally distorted sine wave. So be cautious buying "XR" labelled XR2206 chips nowadays unless you have a reliable source with NOS stock. There is however one version of this chip I got hands on, which was made by HLF (Shenzhen honglifa Electronics); "XR2206CP HLF A8". Clearly a clone but on spec to the original XR2206 datasheet. So maybe try sourcing those HLF clones instead of getting burned by the original XR branded ones.
Suggestion: Design a SABA Radio Test Socket Break-Out Box.
A good idea for when I get another SABA to work on.
Nice!
Simple fix maybe to gear the knob? Turn the gear and the pod goes the other way
Yes, that would work.
Here is a crazy idea! Dismantle the pot and put the shaft from the other end. No idea how you can mount it though :-(
May not be as crazy as that 😊
I would have used a bridge rectifier instead of d5 diode. Then polarity is not an issue
There is a better design possible. I will explain:
You are after a phase shift. If you take an integrator, you will see that it phase shifts.
With two integrations, you can make a two stage low pass filter that has a really high Q. This is not an oscillator but if you could feed in a signal at that frequency, it will clean it up and amplify a lot.
In the classic 3 opamp, integrator based filter, one op-amp is not an integrator. It is simply an inverting amplifier. Instead of limiting to control amplitude in an oscillator, a tiny positive feedback makes that amplifier stage cause the system to oscillate. The up side to this method is that you have very little distortion in the resulting signal.
You can make a lniear pot log with a resistor to ground ratio depends on the resistor you choose
Graphite works two layers gifs a few K 🙃
👍
I apreciate you having some fun but could one just use a signal generator app on an old smartphone?
Sure, but as you’ve guessed … where’s the fun in that? 😊
Actually, since we can listen to practically any radio station on the planet using a phone app, why restore tune radios at all? It’s all in the fun of the hobby for me.
I Know, I know. You could at least ad a lcd with a frequency counter:)
I may actually do just that. Right now I’m reading up on digital pots, and have just received an Amazon pack with 5 arduino nanos 😊
@@electronicsoldandnewWell you are right, then again it is a bit of a skewd argumentation. Until now, and probably still in the future, you will be using ur modern signal generator. That is as high tech as using an old phone with an app.- With maybe a opamp buffer on the headphone output for protection. And even using an old phone as audio frequency scope is a valid approach.
And about your argumentation on using phone to listen to webradio, why repair old radios; you are lucky to still have AM radio stations. Here AM radio was shut down in 2015. And some northern european countries have even done away with analog FM. So for many of us, it is a must to use webradio reception and rebroadcast it to AM unless you want all AM radios to be shelf queens or just be useable at night.
👍
I don't understand, NTC thermistors are common as all hell and cheap as chips? There's 11 68k thermistors on LCSC at the moment, and 21 50ks, hundreds of 10k and 100ks, etc
The problem is getting the correct value for this setup. Try it, by all means. You may get better results than I did.