In typical fashion, he made a video without exploring the functions of the unit. Had he done so, he would have found that pressing the IF button longer he could cycle through 3 different setting, 455khz IF, 10.7Mhz IF and no IF, straight generator mode. The nice thing with this unit is that the amplitude is pretty stable over the wide range not like other junk on the market and thus a step attenuator can be used to make a pretty good signal generator for sensitivity measurements. We bought 10 of them for a school project from different sources, every single one of them was maximal +- 1-5Hz off at 10Mhz. Pretty darn good for a device like this.
@@Guns_N_Gears It is run rom a package for pin XTAL osc chip that provides a reference to for the SI 5351 That's visible on the PCB. you have to find out what the freq is , normally 25 or 27 Mhz. Then build a drop in device that has quality scrver adj capacitor across the xtal and pull it up or down . Far easier said than done given you are partly working in the dark . The weird thing is that the SI supports a direct connected xtal . Perhaps it's not reliable that way ie the xtal has to be special quality to guarantee an OSC start. It's all the Mysteries of the DEEP.
@F_Tim1961 I have messed with one since my original post. I found 1 for 20 some bux and thought to try it out. While they work (kinda), they are quite usless. It seems these are a copy of someone else's work that originally had a calibration option in the menu. This unit does not. I also had it on a scope, and the signal is very dirty as there are no filters in the final stage .
@@Guns_N_Gears Thanks for update . Much appreciated. Perhaps they are using reject Si5351 devices however that chip does not produce even a clean square wave - there's no undertaking from the Si Labs that it has sine wave out. I know where I can get a 10.7 Mhz If SSB filter module so with a sq to sine clean up and that module there May be a future !! :-)) other than that they are pretty useless. Yes going rate on various internet sites is about 25 USD each That barely meets the cost of production. The unit cycles through three different offsets another poster has stated , one of those offsets being Zero.
@@Guns_N_Gears The following chip is a very nice do anything in the Osc cline up to 900 Mhz Osc chip that has complementary OP and can drive out up to -5 dbm into 50 R (both OP used ) as Sine . Obviously you have to square it up to run it into the Si 5135 or perhaps that just wants transitions and a sine wave will work fine as ref std for that. . it is designed to run either with LC or xtal in colpitts mode which can be pulled with a quality adj capacitor say 30 pf . Max2620 You can pick them up for order of 7 USD. from likes of Futurlec company a surplus disposal place. This means you can get the Osc right on frequency which is likely either 25 Mhz or 27 Mhz both defacto stds for the SiLabs line . The clean up of the OP signal is trivial if you mean squaring it up. The AC04 chip will do tha for you up to 50 Mhz, even higher. Above 70 Mhz you may have issues finding a drop in squarer. if you want sine then WEnzel assoc have published RF ccts to do that using a J310 in gnd Gate mode plus a simple LPF . that simulates out fine in LTSpice. BTW back in the day I believe idiots used the Max2620 as the basis for a local cell phone jammer.
the reason the front says transceiver is because it goes with a few other components to make a complete mini ham station, They sell the transmitter and receivers that match this cute lil box
This project is just a copy of the guy that has designed it, and put it on youtube one year ago, see below. Same display layout etc. 10kHz to 225MHz VFO / RF Generator with Si5351 and Arduino Nano, with Intermediate Frequency (IF) offset (+ or -), RX/TX Selector for QRP Transceivers, Band Presets and Bargraph S-Meter. See the schematics for wiring and README.txt for details. By J. CesarSound - ver 2.0 - Feb/2021.
Neat little product as the basis of a transceiver but it's an Arduino, Si5351 breakout, CH340 USB-Serial, TP4056 LiIon charger, SSD1306 OLED, that's what, $15-$20 if you buy them all as modules? That enclosure better be *real* nice for $60
I think it’s because not everyone is an engineer but they want the experience of building something. The VFO is the most complex part of a transceiver and with this it’s plug and play. You’re not spending hours screwing with incompatible sketches etc
A small correction: it is not Arduino based. Both (many of) Arduino's and this device are AVR-based. Atmel was taken over by Microchip several years ago.
So it's designed to be used as the front-panel of a wide-coverage transceiver with a 455 kHz IF, but for some reason it didn't sell, so they put the front-panels in boxes and are trying to sell them as VFO's. But you can't program it to match your IF and you have to make sure that the odd order harmonics are suppressed, at least on xmit. Oh, and they want close to a hundred bucks for them. Good luck with that.
@@stevec5000 itappears to have a a mode according to anohter poste r on ths thread. So if you use the push in button ON the tuning knob the unit displays a frequency + 455 kHz above what it is in infact producing. So if you use the VFO output as an exciter for an RF Mixer then the mixer OP is at 455 Khz. Thre are 455 kHz ceramic filter modules you can purchase - you need to to have an understanding of how the guts of a superhet receiver works for this to be meaningful.
@@IMSAIGuy thank you very much!! But I ask you because in Amazon say for this item (Power 0.1 mw) In dbm there is no logic!! Sorry for my bad English!! 😅
well for data modes you need a signal carrier and then in a second unit you can do the frequency shifting stuff...russia studiec every time 5-6 times the propagation of experimental carriers bevor the applied the MFSK XX stuff ....you can create your personal data mode on HF
I expect the "S-meter input" is meant to be *from* an S-meter, a linear analog voltage representing the signal strength for the display. The absent C7 would deliver another frequency from the synthesizer for a "BFO output" instead.
There could be. But if one wanted to mod the firmware (as opposed to accessing options from the software interface provided) then that could be a rabbit-hole project. I'm guessing that the manufacturers of this thing 'borrowed' the hardware and software design, from somewhere (maybe even from the chip set manufacturer) so there may be a lot of work to do to customize and work out bugs.
Thanks for the interesting video. This thing, with shipping, is the better part of 100 USD, on Prime. For 20 bucks, OK; but, for 20 or 30 dollars more, you can get a complete Chinese wide band SDR receiver. Maybe stuff like this wouldn't see the light of day, beyond China, if it wasn't reviewed, and implicitly recommended on TH-cam.
Here’s a silly question from someone with very little experience with RF stuff: Why do expensive HF radios exist? Given a stable clock, can’t any 300mhz microcontroller output a square wave at ~10mhz which can be amplified with a couple of cheap MOSFETs and filtered with a 2 pole low-pass filter to remove the harmonics and get a band limited signal you can broadcast?
You just described a simple transmitter, which is not the most difficult part of a transceiver. The receiver makes or breaks the performance for a ham operator, and the receiver is much more complicated. Some manufacturers do better jobs than others at that, and that is why expensive HF radios exist. But there are excellent receivers in some less expensive radios, depending on what your goals are.
@@IMSAIGuy Okay, Now that I think about it, I've got a Ham-It-Up up-converter and I think it uses a simple low-pass filter but that is a fixed frequency so that would be pretty easy.
@@IMSAIGuy I thought of it only because I'd just watched your video about protecting the tinysa. I'm expert in laziness and procrastination. I'd say you were just being complacent in this case. :-)
I know some guys are not really used to metric, so I’m already happy about not being confronted with an imperial frequency measurement. But there is big difference between mHz and MHz, as m and M are case sensitive in metric of about 10^9. milli and Mega is not exactly the same 😂
The link to the sales site provides a lot of information of what this little unit fan do. Tuning steps of 1Hz, adjustable IF + or - (so no real need to bodge the switch) The band change is 20 channel programmable The only problem is finding the instructions. It's a useful little box, but really rather too expensive when a simple 5351 and little ardunio / rPi pico wouod do the same job. Looks like a very similar project is on Project Hub by CesarSound published January 2, 2021 The code and circuit is all there. Andy
Good that you tested it. Real Bad harmonics, as a sine wave generator ! If it is square wave let's see it on oscilloscope and look at eye diagram and measure rise time, fall time, and probably jitter.
spotted this on amazonk cute lil box searching for ham radio stuff so off to you tube wondering what is it, this video left me more confused but thanks $75 for a cute lil box {VFO} that can't even sing "me chinese, me play joke, me put pee in your coke" is beyond me.
These sort of metrics I don’t understand. If everything were to break down, so to speak; I would like to have the utility of talking with people over distance. You seem like the person that would know that.
In typical fashion, he made a video without exploring the functions of the unit. Had he done so, he would have found that pressing the IF button longer he could cycle through 3 different setting, 455khz IF, 10.7Mhz IF and no IF, straight generator mode. The nice thing with this unit is that the amplitude is pretty stable over the wide range not like other junk on the market and thus a step attenuator can be used to make a pretty good signal generator for sensitivity measurements. We bought 10 of them for a school project from different sources, every single one of them was maximal +- 1-5Hz off at 10Mhz. Pretty darn good for a device like this.
Can you calibrate it at all, or is that locked out?
@@Guns_N_Gears It is run rom a package for pin XTAL osc chip that provides a reference to for the SI 5351 That's visible on the PCB. you have to find out what the freq is , normally 25 or 27 Mhz. Then build a drop in device that has quality scrver adj capacitor across the xtal and pull it up or down . Far easier said than done given you are partly working in the dark . The weird thing is that the SI supports a direct connected xtal . Perhaps it's not reliable that way ie the xtal has to be special quality to guarantee an OSC start. It's all the Mysteries of the DEEP.
@F_Tim1961 I have messed with one since my original post. I found 1 for 20 some bux and thought to try it out. While they work (kinda), they are quite usless. It seems these are a copy of someone else's work that originally had a calibration option in the menu. This unit does not.
I also had it on a scope, and the signal is very dirty as there are no filters in the final stage .
@@Guns_N_Gears Thanks for update . Much appreciated. Perhaps they are using reject Si5351 devices however that chip does not produce even a clean square wave - there's no undertaking from the Si Labs that it has sine wave out. I know where I can get a 10.7 Mhz If SSB filter module so with a sq to sine clean up and that module there May be a future !! :-)) other than that they are pretty useless. Yes going rate on various internet sites is about 25 USD each That barely meets the cost of production. The unit cycles through three different offsets another poster has stated , one of those offsets being Zero.
@@Guns_N_Gears The following chip is a very nice do anything in the Osc cline up to 900 Mhz Osc chip that has complementary OP and can drive out up to -5 dbm into 50 R (both OP used ) as Sine . Obviously you have to square it up to run it into the Si 5135 or perhaps that just wants transitions and a sine wave will work fine as ref std for that. . it is designed to run either with LC or xtal in colpitts mode which can be pulled with a quality adj capacitor say 30 pf . Max2620 You can pick them up for order of 7 USD. from likes of Futurlec company a surplus disposal place. This means you can get the Osc right on frequency which is likely either 25 Mhz or 27 Mhz both defacto stds for the SiLabs line .
The clean up of the OP signal is trivial if you mean squaring it up. The AC04 chip will do tha for you up to 50 Mhz, even higher. Above 70 Mhz you may have issues finding a drop in squarer. if you want sine then WEnzel assoc have published RF ccts to do that using a J310 in gnd Gate mode plus a simple LPF . that simulates out fine in LTSpice.
BTW back in the day I believe idiots used the Max2620 as the basis for a local cell phone jammer.
the reason the front says transceiver is because it goes with a few other components to make a complete mini ham station, They sell the transmitter and receivers that match this cute lil box
This project is just a copy of the guy that has designed it, and put it on youtube one year ago, see below.
Same display layout etc.
10kHz to 225MHz VFO / RF Generator with Si5351 and Arduino Nano, with Intermediate Frequency (IF) offset
(+ or -), RX/TX Selector for QRP Transceivers, Band Presets and Bargraph S-Meter. See the schematics for
wiring and README.txt for details. By J. CesarSound - ver 2.0 - Feb/2021.
Neat little product as the basis of a transceiver but it's an Arduino, Si5351 breakout, CH340 USB-Serial, TP4056 LiIon charger, SSD1306 OLED, that's what, $15-$20 if you buy them all as modules? That enclosure better be *real* nice for $60
I think it’s because not everyone is an engineer but they want the experience of building something. The VFO is the most complex part of a transceiver and with this it’s plug and play. You’re not spending hours screwing with incompatible sketches etc
@@justinelliott3529 😅
Nice little build and now you tidied it up even better...cheers.
It's only missing a single IC chip. Connect the output line to a Tayloe circuit and you have IQ for your sound card SDR apps.
How to change IF frequency to another one ?
A small correction: it is not Arduino based. Both (many of) Arduino's and this device are AVR-based. Atmel was taken over by Microchip several years ago.
Output port is mis-labeled. Frequencies in kelvin hertz (KHz) to mega hertz (MHz). Should be kilo hertz (kHz) to mega hertz (MHz).
It's ... I hate to say it... Chinese junk... part of some manufacturing, someone in China picked up, and decided to put in a case and sell.
you would like Kaplan America's channel!
✅😎kool vids …👍
Hello would this be good to use on the ubitx v3 to controll the frequencies ?? 🎉🎉
I have one of these. Is is possible to program a different IF shift? (I need 2.920 MHZ).
So it's designed to be used as the front-panel of a wide-coverage transceiver with a 455 kHz IF, but for some reason it didn't sell, so they put the front-panels in boxes and are trying to sell them as VFO's. But you can't program it to match your IF and you have to make sure that the odd order harmonics are suppressed, at least on xmit. Oh, and they want close to a hundred bucks for them. Good luck with that.
How does it work with a transceiver with a 455 kHz IF? Is it what you use to set the rec. frequency?
@@stevec5000 itappears to have a a mode according to anohter poste r on ths thread. So if you use the push in button ON the tuning knob the unit displays a frequency + 455 kHz above what it is in infact producing. So if you use the VFO output as an exciter for an RF Mixer then the mixer OP is at 455 Khz. Thre are 455 kHz ceramic filter modules you can purchase - you need to to have an understanding of how the guts of a superhet receiver works for this to be meaningful.
hello my friend!! i want to ask how much mV have the generator?
+12dBm is 0.9Vrms into 50 ohms
@@IMSAIGuy thank you very much!! But I ask you because in Amazon say for this item (Power 0.1 mw)
In dbm there is no logic!!
Sorry for my bad English!! 😅
@@IMSAIGuy
1V rms squared div 50 is 0.020 mW take 10* Logten of that as mW and you get 13 dBm yes you got it right...
well for data modes you need a signal carrier and then in a second unit you can do the frequency shifting stuff...russia studiec every time 5-6 times the propagation of experimental carriers bevor the applied the MFSK XX stuff ....you can create your personal data mode on HF
I expect the "S-meter input" is meant to be *from* an S-meter, a linear analog voltage representing the signal strength for the display. The absent C7 would deliver another frequency from the synthesizer for a "BFO output" instead.
For thr viewers, the IF is selectable by long pressing the IF button, and the display iaroind .96.
Its useless!!
220 mHz = 0.22Hz !!!!!!!!!!!!!
Seems like there would be software options for the direction and IF settings. Surely it can tune in finer steps than 5kc too.
There could be. But if one wanted to mod the firmware (as opposed to accessing options from the software interface provided) then that could be a rabbit-hole project. I'm guessing that the manufacturers of this thing 'borrowed' the hardware and software design, from somewhere (maybe even from the chip set manufacturer) so there may be a lot of work to do to customize and work out bugs.
Thanks for the interesting video. This thing, with shipping, is the better part of 100 USD, on Prime. For 20 bucks, OK; but, for 20 or 30 dollars more, you can get a complete Chinese wide band SDR receiver. Maybe stuff like this wouldn't see the light of day, beyond China, if it wasn't reviewed, and implicitly recommended on TH-cam.
can u make a video about ad 9851 dds i cant get a steady sine wave even in under 5 Mhz from it. tnx in advance
I did this video: th-cam.com/video/9_A-HeUK_5g/w-d-xo.html
actually a two part
My original project working in a superhet receiver: th-cam.com/video/72dXGVvUaE8/w-d-xo.html
excellent, looks like fun
For those with quadrature encoders, swap either the two phase A wires or the two phase B wires -- don't swap A wires for B wires.
there is only three wires
Here’s a silly question from someone with very little experience with RF stuff: Why do expensive HF radios exist? Given a stable clock, can’t any 300mhz microcontroller output a square wave at ~10mhz which can be amplified with a couple of cheap MOSFETs and filtered with a 2 pole low-pass filter to remove the harmonics and get a band limited signal you can broadcast?
You just described a simple transmitter, which is not the most difficult part of a transceiver. The receiver makes or breaks the performance for a ham operator, and the receiver is much more complicated. Some manufacturers do better jobs than others at that, and that is why expensive HF radios exist. But there are excellent receivers in some less expensive radios, depending on what your goals are.
Isn't the thing kind of worthless given all the harmonics? I was also wondering about jitter.
almost all the DDS chips are square waves, they are not useless, just require care and filtering to use.
@@IMSAIGuy Okay, Now that I think about it, I've got a Ham-It-Up up-converter and I think it uses a simple low-pass filter but that is a fixed frequency so that would be pretty easy.
PSA suggestion: Always show insertion of attenuator when testing unknown sources(though this battery powered thingy unlikely high power).
I should. I am very sloppy in my lab because the HP spectrum analyzer is protected to +30dBm.
@@IMSAIGuy I thought of it only because I'd just watched your video about protecting the tinysa.
I'm expert in laziness and procrastination. I'd say you were just being complacent in this case. :-)
Is it Okay to call a square wave generator "VFO" for a receiver?
Yes, it is. Doubly balanced diode mixers perform better with square wave LO input. It just requires filtering at the output, that is all.
I know some guys are not really used to metric, so I’m already happy about not being confronted with an imperial frequency measurement. But there is big difference between mHz and MHz, as m and M are case sensitive in metric of about 10^9.
milli and Mega is not exactly the same 😂
The link to the sales site provides a lot of information of what this little unit fan do.
Tuning steps of 1Hz, adjustable IF + or - (so no real need to bodge the switch)
The band change is 20 channel programmable
The only problem is finding the instructions.
It's a useful little box, but really rather too expensive when a simple 5351 and little ardunio / rPi pico wouod do the same job.
Looks like a very similar project is on Project Hub by CesarSound published January 2, 2021
The code and circuit is all there.
Andy
this gives me a headache!!!
You should connect that to the IC-245! Ha!
No Kiddin' . I might get one for mine.
STOP FUNDINGG THE CHINESE AND SUPPORT DL2MAN WHO DESIGNED THIS GREAT RIG......
Good that you tested it. Real Bad harmonics, as a sine wave generator ! If it is square wave let's see it on oscilloscope and look at eye diagram and measure rise time, fall time, and probably jitter.
It's got an Si5351, it's definitely square wave.
@@M0UAW_IO83 I think it is to be used for Ref. clock of PLL.
spotted this on amazonk cute lil box searching for ham radio stuff so off to you tube wondering what is it, this video left me more confused but thanks $75 for a cute lil box {VFO} that can't even sing "me chinese, me play joke, me put pee in your coke" is beyond me.
Put a toggle switch for PTT
These sort of metrics I don’t understand. If everything were to break down, so to speak; I would like to have the utility of talking with people over distance. You seem like the person that would know that.