Hardware 3 phase generator from sed - 3 phase generator.asc
Combined filter/coil driver functions and used a spare opamp to get
the Q3 inversion to feed back to D1. I used LT1677's 'cause they were in the LTspice database, and handy, but there are probably other parts out there that would work as well, for less money. Not a perfect sine wave, but not bad; take a look at the FFT. --- JF |
Hardware 3 phase generator from sed - 3 phase generator.asc
John Fields wrote:
Combined filter/coil driver functions and used a spare opamp to get the Q3 inversion to feed back to D1. I used LT1677's 'cause they were in the LTspice database, and handy, but there are probably other parts out there that would work as well, for less money. Not a perfect sine wave, but not bad; take a look at the FFT. --- JF Nice. This thing "simulates" nicely on breadboard, as well as spice. :-) I put it together with stuff I had on hand - the op amp is a 324, no matched caps or R's - and it actually looks a little better on the scope than in spice. Not sure if I can get clear waveform photos, but I'll try if you want. Ed |
Hardware 3 phase generator from sed - 3 phase generator.asc
On Wed, 24 Nov 2010 21:02:19 -0500, ehsjr
wrote: John Fields wrote: Combined filter/coil driver functions and used a spare opamp to get the Q3 inversion to feed back to D1. I used LT1677's 'cause they were in the LTspice database, and handy, but there are probably other parts out there that would work as well, for less money. Not a perfect sine wave, but not bad; take a look at the FFT. --- JF Nice. This thing "simulates" nicely on breadboard, as well as spice. :-) I put it together with stuff I had on hand - the op amp is a 324, no matched caps or R's - and it actually looks a little better on the scope than in spice. Not sure if I can get clear waveform photos, but I'll try if you want. Ed --- Sure, that would be great! Thanks :-) --- JF |
Hardware 3 phase generator from sed - 3 phase generator.asc
4 Attachment(s)
John Fields wrote:
On Wed, 24 Nov 2010 21:02:19 -0500, ehsjr wrote: John Fields wrote: Combined filter/coil driver functions and used a spare opamp to get the Q3 inversion to feed back to D1. I used LT1677's 'cause they were in the LTspice database, and handy, but there are probably other parts out there that would work as well, for less money. Not a perfect sine wave, but not bad; take a look at the FFT. --- JF Nice. This thing "simulates" nicely on breadboard, as well as spice. :-) I put it together with stuff I had on hand - the op amp is a 324, no matched caps or R's - and it actually looks a little better on the scope than in spice. Not sure if I can get clear waveform photos, but I'll try if you want. Ed --- Sure, that would be great! Thanks :-) --- JF Ok, here's my "photographic genius" ( :-( ) on display. I tried taking pictures in the dark last night at ~ 19Hz, but they were awful. In the daytime, I had to take the pictures under a towel to keep ambient light out - I would not be surprised to hear there's a better way. (See Daylight.jpg for no towel) Frequency was ~39 Hz (see Sine ph1 & 3 on the far right for frequency readout, and Sine ph1 & ph2 for sweep & V/div). Aside from the photographic issues, the sine looks pretty good. :-) I'll bet the op would be happy with your circuit if he tried it. Ed |
Hardware 3 phase generator from sed - 3 phase generator.asc
On Fri, 26 Nov 2010 14:13:42 -0500, ehsjr
wrote: John Fields wrote: On Wed, 24 Nov 2010 21:02:19 -0500, ehsjr wrote: John Fields wrote: Combined filter/coil driver functions and used a spare opamp to get the Q3 inversion to feed back to D1. I used LT1677's 'cause they were in the LTspice database, and handy, but there are probably other parts out there that would work as well, for less money. Not a perfect sine wave, but not bad; take a look at the FFT. --- JF Nice. This thing "simulates" nicely on breadboard, as well as spice. :-) I put it together with stuff I had on hand - the op amp is a 324, no matched caps or R's - and it actually looks a little better on the scope than in spice. Not sure if I can get clear waveform photos, but I'll try if you want. Ed --- Sure, that would be great! Thanks :-) --- JF Ok, here's my "photographic genius" ( :-( ) on display. I tried taking pictures in the dark last night at ~ 19Hz, but they were awful. In the daytime, I had to take the pictures under a towel to keep ambient light out - I would not be surprised to hear there's a better way. (See Daylight.jpg for no towel) Frequency was ~39 Hz (see Sine ph1 & 3 on the far right for frequency readout, and Sine ph1 & ph2 for sweep & V/div). Aside from the photographic issues, the sine looks pretty good. :-) I'll bet the op would be happy with your circuit if he tried it. Ed --- Not bad shots, they show what's going on... :-) Strange kinda guy; he only made two posts over the course of the entire thread. Thanks again for the photos and the real-world testing. --- JF |
Hardware 3 phase generator from sed - 3 phase generator.asc
In article ,
John Fields wrote: Combined filter/coil driver functions and used a spare opamp to get the Q3 inversion to feed back to D1. I used LT1677's 'cause they were in the LTspice database, and handy, but there are probably other parts out there that would work as well, for less money. Not a perfect sine wave, but not bad; take a look at the FFT. --- JF begin 644 3 phase generator.asc [Image] end Could you repost? Thanks Larry |
Hardware 3 phase generator from sed - 3 phase generator.asc - 3 phase generator.asc
On Tue, 16 Aug 2011 18:43:12 -0400, "Lawrance A. Schneider"
wrote: In article , John Fields wrote: Combined filter/coil driver functions and used a spare opamp to get the Q3 inversion to feed back to D1. I used LT1677's 'cause they were in the LTspice database, and handy, but there are probably other parts out there that would work as well, for less money. Not a perfect sine wave, but not bad; take a look at the FFT. --- JF |
All times are GMT +1. The time now is 12:46 AM. |
Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2014 DIYbanter