On a sunny day (Fri, 14 Dec 2012 22:28:33 -0500) it happened Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in <7qnnc854riik80b1ui4ldnoihl3o89s704@4ax.com>:>Microchip's Configurable Logic Cells are interesting- incorporating a >few gates or even a logic-level 555-equivalant onto the chip, though >I've not yet had occasion to use that functionality.I dunno, but for a function generator just use a FPGA with internal RAM loaded from the PC and any DAC you think suites the purpose. PWM ADC is suited only for very low frequencies. Somebody here from Germany already did such a project: http://www.frank-buss.de/SignalGenerator/
are all the function generators gone?
Started by ●December 12, 2012
Reply by ●December 15, 20122012-12-15
Reply by ●December 15, 20122012-12-15
On Sat, 15 Dec 2012 09:24:51 GMT, the renowned Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote:>On a sunny day (Fri, 14 Dec 2012 22:28:33 -0500) it happened Spehro Pefhany ><speffSNIP@interlogDOTyou.knowwhat> wrote in ><7qnnc854riik80b1ui4ldnoihl3o89s704@4ax.com>: > >>Microchip's Configurable Logic Cells are interesting- incorporating a >>few gates or even a logic-level 555-equivalant onto the chip, though >>I've not yet had occasion to use that functionality. > >I dunno, but for a function generator just use a FPGA with internal RAM loaded from the PC >and any DAC you think suites the purpose. >PWM ADC is suited only for very low frequencies.I suggested using a micro with a real DAC on board, but 125kHz 8-bit PWM should be more than okay for something like Bell 202 AFSK- so one <$2 chip and a very simple filter (and some tedious hours coding it).> >Somebody here from Germany already did such a project: > http://www.frank-buss.de/SignalGenerator/Nicely done. Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
Reply by ●December 15, 20122012-12-15
On a sunny day (Sat, 15 Dec 2012 11:10:53 -0500) it happened Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in <ij6pc8d0bsp98kjtm5mjd10p5mc9ca04o5@4ax.com>:>On Sat, 15 Dec 2012 09:24:51 GMT, the renowned Jan Panteltje ><pNaonStpealmtje@yahoo.com> wrote: > >>On a sunny day (Fri, 14 Dec 2012 22:28:33 -0500) it happened Spehro Pefhany >><speffSNIP@interlogDOTyou.knowwhat> wrote in >><7qnnc854riik80b1ui4ldnoihl3o89s704@4ax.com>: >> >>>Microchip's Configurable Logic Cells are interesting- incorporating a >>>few gates or even a logic-level 555-equivalant onto the chip, though >>>I've not yet had occasion to use that functionality. >> >>I dunno, but for a function generator just use a FPGA with internal RAM loaded from the PC >>and any DAC you think suites the purpose. >>PWM ADC is suited only for very low frequencies. > >I suggested using a micro with a real DAC on board, but 125kHz 8-bit >PWM should be more than okay for something like Bell 202 AFSK- so one ><$2 chip and a very simple filter (and some tedious hours coding it).Sure, I think I have a dial tones in PIC application note from Microchip. For a very simple PIC.>>Somebody here from Germany already did such a project: >> http://www.frank-buss.de/SignalGenerator/ > >Nicely done.He does really nice projects.
Reply by ●December 15, 20122012-12-15
On Wed, 12 Dec 2012 15:14:48 -0800 (PST), George Herold <gherold@teachspin.com> wrote:> >> MAX038 is gone, too. Jameco has some 2206 DIPs, which I could scoop >> up, I guess. > >Do you need a lot? We've got several tubes left over from a >discontinued >gizmo*. >Wow. i am surprised that there are any 2206 or 8038 types left anywhere.>> >> Anybody know of a classic analog sinewave generator chip? A uP and DDS >> would be a lot of hassle. And I'd like to be able to set the >> mark/space frequencies with pots. >> >> I guess I could make a triangle oscillator and sort of bend it into a >> sine wave. THD wouldn't matter much. > >You could use a clocked 4017 with different R's into a opamp summing >junction. (Phil or James suggested it a while back.) With ten steps >you move most of the 'distortion' out to the 9th and 11th harmonic. > >George H. > >*Teachscope, sold for a few hundred and put out 12 different 'signals' >that the students would have to 'go find' with a 'scope. I wish >someone would make the current day equivalent out of a uC.So do you have the specs on that teachscope thing? If it is within my grasp i might try it. I am not really sure what i may be getting myself into here, i could easily hit a hole (more likely a rot spot) in my edumacation. ?-)
Reply by ●December 15, 20122012-12-15
On Sat, 15 Dec 2012 09:16:36 -0800, josephkk <joseph_barrett@sbcglobal.net> wrote:>On Wed, 12 Dec 2012 15:14:48 -0800 (PST), George Herold ><gherold@teachspin.com> wrote: > >> >>> MAX038 is gone, too. Jameco has some 2206 DIPs, which I could scoop >>> up, I guess. >> >>Do you need a lot? We've got several tubes left over from a >>discontinued >>gizmo*.>Wow. i am surprised that there are any 2206 or 8038 types left anywhere.>>> Anybody know of a classic analog sinewave generator chip? A uP and DDS >>> would be a lot of hassle. And I'd like to be able to set the >>> mark/space frequencies with pots. >>> >>> I guess I could make a triangle oscillator and sort of bend it into a >>> sine wave. THD wouldn't matter much. >> >>You could use a clocked 4017 with different R's into a opamp summing >>junction. (Phil or James suggested it a while back.) With ten steps >>you move most of the 'distortion' out to the 9th and 11th harmonic. >> >>George H. >> >>*Teachscope, sold for a few hundred and put out 12 different 'signals' >>that the students would have to 'go find' with a 'scope. I wish >>someone would make the current day equivalent out of a uC. > >So do you have the specs on that teachscope thing? If it is within my >grasp i might try it. I am not really sure what i may be getting myself >into here, i could easily hit a hole (more likely a rot spot) in my >edumacation.George and I had exchanged some discussions about a year ago and he sent me a sample board (they made 12 different units -- variations on a theme -- but he sent no power supply or casing) to try out. I put some time into thinking about a few things, but other work has taken priority. (Our discussions were without any commitment either way, as I recall it.) George can speak for himself, obviously. But I think there is an interest, also, in updating the system so that it helps teach users aspects of using both analog and digital scopes. So there are lots of room for suggesting ideas, I suspect. In any case, if you decide to get moving on something like this I could certainly send you the unit that George sent to me (he may be in short supply.) And if you feel there is anything you may be able to accept, by way of help, I'd be happy to work with you on whatever basis you wanted. My only interest would be in furthering this for George's interest. I'd like to do that, if I can. But otherwise, if all I do is pass along some information then I'd be happy with that role, too. Let me know. Jon
Reply by ●December 17, 20122012-12-17
On Dec 15, 12:16=A0pm, josephkk <joseph_barr...@sbcglobal.net> wrote:> On Wed, 12 Dec 2012 15:14:48 -0800 (PST), George Herold > > <gher...@teachspin.com> wrote: > > >> MAX038 is gone, too. Jameco has some 2206 DIPs, which I could scoop > >> up, I guess. > > >Do you need a lot? =A0We've got several tubes left over from a > >discontinued > >gizmo*. > > Wow. i am surprised that there are any 2206 or 8038 types left anywhere. > > > > > > > > >> Anybody know of a classic analog sinewave generator chip? A uP and DDS > >> would be a lot of hassle. And I'd like to be able to set the > >> mark/space frequencies with pots. > > >> I guess I could make a triangle oscillator and sort of bend it into a > >> sine wave. THD wouldn't matter much. > > >You could use a clocked 4017 with different R's into a opamp summing > >junction. =A0(Phil or James suggested it a while back.) =A0With ten step=s> >you move most of the 'distortion' out to the 9th and 11th harmonic. > > >George H. > > >*Teachscope, sold for a few hundred and put out 12 different 'signals' > >that the students would have to 'go find' with a 'scope. =A0I wish > >someone would make the current day equivalent out of a uC. > > So do you have the specs on that teachscope thing? =A0If it is within my > grasp i might try it. =A0I am not really sure what i may be getting mysel=f> into here, i could easily hit a hole (more likely a rot spot) in my > edumacation. > > ?-)- Hide quoted text - > > - Show quoted text -Hi Joseph, Well there are no real 'specs'. The idea is a cheap device that spits out different waveforms. Students (moslty physics undergrads, for my market) learn how to use a 'scope by finding all the waveforms. So different time bases, vertical gains, AC and DC coupling, auto and normal triggering. Hmm, As I'm writing this, I wonder if the 'autoset' button on newer 'scopes makes all this moot? (I never use the auto set button so I've no idea how well it works.) OK, I dug an old board out of stock, today The autoset button on my TEK found everything but the very slow (few Hz.) waveforms. It'd be nice if the next version of teachscope had a few settings where there were two (or more?) signals at different levels/times. (Now I'm in an 'arms race' with the autoset button?) I hope I haven't misled you with talk of 1,000 of units. I'd like someone to make/sell thousands so I could ask my customers to buy them (at the tens to a hundred a year rate) We stopped making it because it was too big an expense to get another batch of boxes printed. (We were also getting low on cheap brick on a rope PS's) (Box, PS, switch, connector) As I've said before, the electronics inside is almost free. George H.
Reply by ●December 17, 20122012-12-17
On Dec 15, 1:53=A0pm, Jon Kirwan <j...@infinitefactors.org> wrote:> On Sat, 15 Dec 2012 09:16:36 -0800, josephkk > > > > > > <joseph_barr...@sbcglobal.net> wrote: > >On Wed, 12 Dec 2012 15:14:48 -0800 (PST), George Herold > ><gher...@teachspin.com> wrote: > > >>> MAX038 is gone, too. Jameco has some 2206 DIPs, which I could scoop > >>> up, I guess. > > >>Do you need a lot? =A0We've got several tubes left over from a > >>discontinued > >>gizmo*. > >Wow. i am surprised that there are any 2206 or 8038 types left anywhere. > >>> Anybody know of a classic analog sinewave generator chip? A uP and DD=S> >>> would be a lot of hassle. And I'd like to be able to set the > >>> mark/space frequencies with pots. > > >>> I guess I could make a triangle oscillator and sort of bend it into a > >>> sine wave. THD wouldn't matter much. > > >>You could use a clocked 4017 with different R's into a opamp summing > >>junction. =A0(Phil or James suggested it a while back.) =A0With ten ste=ps> >>you move most of the 'distortion' out to the 9th and 11th harmonic. > > >>George H. > > >>*Teachscope, sold for a few hundred and put out 12 different 'signals' > >>that the students would have to 'go find' with a 'scope. =A0I wish > >>someone would make the current day equivalent out of a uC. > > >So do you have the specs on that teachscope thing? =A0If it is within my > >grasp i might try it. =A0I am not really sure what i may be getting myse=lf> >into here, i could easily hit a hole (more likely a rot spot) in my > >edumacation. > > George and I had exchanged some discussions about a year ago > and he sent me a sample board (they made 12 different units > -- variations on a theme -- but he sent no power supply or > casing) to try out. I put some time into thinking about a few > things, but other work has taken priority. (Our discussions > were without any commitment either way, as I recall it.) > > George can speak for himself, obviously. But I think there is > an interest, also, in updating the system so that it helps > teach users aspects of using both analog and digital scopes. > So there are lots of room for suggesting ideas, I suspect. > > In any case, if you decide to get moving on something like > this I could certainly send you the unit that George sent to > me (he may be in short supply.) And if you feel there is > anything you may be able to accept, by way of help, I'd be > happy to work with you on whatever basis you wanted. My only > interest would be in furthering this for George's interest. > I'd like to do that, if I can. But otherwise, if all I do is > pass along some information then I'd be happy with that role, > too. > > Let me know. > > Jon- Hide quoted text - > > - Show quoted text -Grin, Thanks Jon, my interest is totally selfish, I wish more of my customers knew how to drive a 'scope. George H.
Reply by ●December 18, 20122012-12-18
On Mon, 17 Dec 2012 17:53:07 -0800 (PST), patricia herold <pmdherold@gmail.com> wrote:>On Dec 15, 12:16=A0pm, josephkk <joseph_barr...@sbcglobal.net> wrote: >> On Wed, 12 Dec 2012 15:14:48 -0800 (PST), George Herold >> >> <gher...@teachspin.com> wrote: >> >> >> MAX038 is gone, too. Jameco has some 2206 DIPs, which I could scoop >> >> up, I guess. >> >> >Do you need a lot? =A0We've got several tubes left over from a >> >discontinued >> >gizmo*. >> >> Wow. i am surprised that there are any 2206 or 8038 types left =anywhere.>> >> >> >> >> >> >> >> >> Anybody know of a classic analog sinewave generator chip? A uP and =DDS>> >> would be a lot of hassle. And I'd like to be able to set the >> >> mark/space frequencies with pots. >> >> >> I guess I could make a triangle oscillator and sort of bend it into=a>> >> sine wave. THD wouldn't matter much. >> >> >You could use a clocked 4017 with different R's into a opamp summing >> >junction. =A0(Phil or James suggested it a while back.) =A0With ten =steps>> >you move most of the 'distortion' out to the 9th and 11th harmonic. >> >> >George H. >> >> >*Teachscope, sold for a few hundred and put out 12 different ='signals'>> >that the students would have to 'go find' with a 'scope. =A0I wish >> >someone would make the current day equivalent out of a uC. >> >> So do you have the specs on that teachscope thing? =A0If it is within =my>> grasp i might try it. =A0I am not really sure what i may be getting =myself>> into here, i could easily hit a hole (more likely a rot spot) in my >> edumacation. >> >> ?-)- Hide quoted text - >> >> - Show quoted text - > >Hi Joseph, Well there are no real 'specs'. The idea is a cheap >device that spits out different waveforms. Students (moslty physics >undergrads, for my market) learn how to use a 'scope by finding all >the waveforms. >So different time bases, vertical gains, AC and DC coupling, auto and >normal triggering. > > > Hmm, As I'm writing this, I wonder if the 'autoset' button on newer >'scopes makes all this moot? (I never use the auto set button so >I've no idea how well it works.) > >OK, I dug an old board out of stock, today The autoset button on my >TEK found everything but the very slow (few Hz.) waveforms. It'd be >nice if the next version of teachscope had a few settings where there >were two (or more?) signals at different levels/times. (Now I'm in an >'arms race' with the autoset button?) > >I hope I haven't misled you with talk of 1,000 of units. I'd like >someone to make/sell thousands so I could ask my customers to buy them >(at the tens to a hundred a year rate) >We stopped making it because it was too big an expense to get another >batch of boxes printed. (We were also getting low on cheap brick on a >rope PS's) >(Box, PS, switch, connector) As I've said before, the electronics >inside is almost free. > >George H.Hmmmm. I think i have some beautiful ways to make autoset very challenging, a few modulated signals with the modulation signal appearing elsewhere. And we can produce many more signals easily so long as they = do not have to be really high quality of their type. Maybe 30 to 50 = signals? Indeed, low quality signals may be more challenging. +/- 12 and 15 V stuff is getting scarce, maybe we want to change to +/- 5 V analog and 3.3 V logic. As you say packaging and PS are major cost items, let's see what we can do about that. ?-)
Reply by ●December 18, 20122012-12-18
On Mon, 17 Dec 2012 22:53:12 -0800, josephkk <joseph_barrett@sbcglobal.net> wrote:>On Mon, 17 Dec 2012 17:53:07 -0800 (PST), patricia herold ><pmdherold@gmail.com> wrote: > >>On Dec 15, 12:16�pm, josephkk <joseph_barr...@sbcglobal.net> wrote: >>> On Wed, 12 Dec 2012 15:14:48 -0800 (PST), George Herold >>> >>> <gher...@teachspin.com> wrote: >>> >>> >> MAX038 is gone, too. Jameco has some 2206 DIPs, which I could scoop >>> >> up, I guess. >>> >>> >Do you need a lot? �We've got several tubes left over from a >>> >discontinued >>> >gizmo*. >>> >>> Wow. i am surprised that there are any 2206 or 8038 types left anywhere. >>> >>> >>> >>> >>> >>> >>> >>> >> Anybody know of a classic analog sinewave generator chip? A uP and DDS >>> >> would be a lot of hassle. And I'd like to be able to set the >>> >> mark/space frequencies with pots. >>> >>> >> I guess I could make a triangle oscillator and sort of bend it into a >>> >> sine wave. THD wouldn't matter much. >>> >>> >You could use a clocked 4017 with different R's into a opamp summing >>> >junction. �(Phil or James suggested it a while back.) �With ten steps >>> >you move most of the 'distortion' out to the 9th and 11th harmonic. >>> >>> >George H. >>> >>> >*Teachscope, sold for a few hundred and put out 12 different 'signals' >>> >that the students would have to 'go find' with a 'scope. �I wish >>> >someone would make the current day equivalent out of a uC. >>> >>> So do you have the specs on that teachscope thing? �If it is within my >>> grasp i might try it. �I am not really sure what i may be getting myself >>> into here, i could easily hit a hole (more likely a rot spot) in my >>> edumacation. >>> >>> ?-)- Hide quoted text - >>> >>> - Show quoted text - >> >>Hi Joseph, Well there are no real 'specs'. The idea is a cheap >>device that spits out different waveforms. Students (moslty physics >>undergrads, for my market) learn how to use a 'scope by finding all >>the waveforms. >>So different time bases, vertical gains, AC and DC coupling, auto and >>normal triggering. >> >> >> Hmm, As I'm writing this, I wonder if the 'autoset' button on newer >>'scopes makes all this moot? (I never use the auto set button so >>I've no idea how well it works.) >> >>OK, I dug an old board out of stock, today The autoset button on my >>TEK found everything but the very slow (few Hz.) waveforms. It'd be >>nice if the next version of teachscope had a few settings where there >>were two (or more?) signals at different levels/times. (Now I'm in an >>'arms race' with the autoset button?) >> >>I hope I haven't misled you with talk of 1,000 of units. I'd like >>someone to make/sell thousands so I could ask my customers to buy them >>(at the tens to a hundred a year rate) >>We stopped making it because it was too big an expense to get another >>batch of boxes printed. (We were also getting low on cheap brick on a >>rope PS's) >>(Box, PS, switch, connector) As I've said before, the electronics >>inside is almost free. >> >>George H. > >Hmmmm. I think i have some beautiful ways to make autoset very >challenging, a few modulated signals with the modulation signal appearing >elsewhere. And we can produce many more signals easily so long as they do >not have to be really high quality of their type. Maybe 30 to 50 signals? >Indeed, low quality signals may be more challenging. > >+/- 12 and 15 V stuff is getting scarce, maybe we want to change to +/- 5 >V analog and 3.3 V logic. As you say packaging and PS are major cost >items, let's see what we can do about that. > >?-)If you do move forward on this, I'd appreciate being kept in the loop at some level acceptable to you. I'm very interested if that's okay. Thanks, Jon
Reply by ●December 18, 20122012-12-18
On Tue, 18 Dec 2012 11:37:29 -0800, Jon Kirwan <jonk@infinitefactors.org> wrote:>On Mon, 17 Dec 2012 22:53:12 -0800, josephkk ><joseph_barrett@sbcglobal.net> wrote: > >>On Mon, 17 Dec 2012 17:53:07 -0800 (PST), patricia herold >><pmdherold@gmail.com> wrote: >> >>>On Dec 15, 12:16�pm, josephkk <joseph_barr...@sbcglobal.net> wrote: >>>> On Wed, 12 Dec 2012 15:14:48 -0800 (PST), George Herold >>>> >>>> <gher...@teachspin.com> wrote: >>>> >>>> >> MAX038 is gone, too. Jameco has some 2206 DIPs, which I could scoop >>>> >> up, I guess. >>>> >>>> >Do you need a lot? �We've got several tubes left over from a >>>> >discontinued >>>> >gizmo*. >>>> >>>> Wow. i am surprised that there are any 2206 or 8038 types left anywhere. >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >> Anybody know of a classic analog sinewave generator chip? A uP and DDS >>>> >> would be a lot of hassle. And I'd like to be able to set the >>>> >> mark/space frequencies with pots. >>>> >>>> >> I guess I could make a triangle oscillator and sort of bend it into a >>>> >> sine wave. THD wouldn't matter much. >>>> >>>> >You could use a clocked 4017 with different R's into a opamp summing >>>> >junction. �(Phil or James suggested it a while back.) �With ten steps >>>> >you move most of the 'distortion' out to the 9th and 11th harmonic. >>>> >>>> >George H. >>>> >>>> >*Teachscope, sold for a few hundred and put out 12 different 'signals' >>>> >that the students would have to 'go find' with a 'scope. �I wish >>>> >someone would make the current day equivalent out of a uC. >>>> >>>> So do you have the specs on that teachscope thing? �If it is within my >>>> grasp i might try it. �I am not really sure what i may be getting myself >>>> into here, i could easily hit a hole (more likely a rot spot) in my >>>> edumacation. >>>> >>>> ?-)- Hide quoted text - >>>> >>>> - Show quoted text - >>> >>>Hi Joseph, Well there are no real 'specs'. The idea is a cheap >>>device that spits out different waveforms. Students (moslty physics >>>undergrads, for my market) learn how to use a 'scope by finding all >>>the waveforms. >>>So different time bases, vertical gains, AC and DC coupling, auto and >>>normal triggering. >>> >>> >>> Hmm, As I'm writing this, I wonder if the 'autoset' button on newer >>>'scopes makes all this moot? (I never use the auto set button so >>>I've no idea how well it works.) >>> >>>OK, I dug an old board out of stock, today The autoset button on my >>>TEK found everything but the very slow (few Hz.) waveforms. It'd be >>>nice if the next version of teachscope had a few settings where there >>>were two (or more?) signals at different levels/times. (Now I'm in an >>>'arms race' with the autoset button?) >>> >>>I hope I haven't misled you with talk of 1,000 of units. I'd like >>>someone to make/sell thousands so I could ask my customers to buy them >>>(at the tens to a hundred a year rate) >>>We stopped making it because it was too big an expense to get another >>>batch of boxes printed. (We were also getting low on cheap brick on a >>>rope PS's) >>>(Box, PS, switch, connector) As I've said before, the electronics >>>inside is almost free. >>> >>>George H. >> >>Hmmmm. I think i have some beautiful ways to make autoset very >>challenging, a few modulated signals with the modulation signal appearing >>elsewhere. And we can produce many more signals easily so long as they do >>not have to be really high quality of their type. Maybe 30 to 50 signals? >>Indeed, low quality signals may be more challenging. >> >>+/- 12 and 15 V stuff is getting scarce, maybe we want to change to +/- 5 >>V analog and 3.3 V logic. As you say packaging and PS are major cost >>items, let's see what we can do about that. >> >>?-) > >If you do move forward on this, I'd appreciate being kept in >the loop at some level acceptable to you. I'm very interested >if that's okay. > >Thanks, >JonAn old (BC, before CAD) design of mine, a little hard to read... http://www.analog-innovations.com/SED/Function_Generator_OmniComp-GenRad.pdf Takes Analog Devices parts, with embellishment, to improve sine wave distortion; and methods to adjust frequency, etc, nicely. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
