danielm said:
Hey Russ, tell me about that amp.
You can read about it here:
http://www.diyaudio.com/forums/showthread.php?postid=1020886#post1020886
Here is how it looks with its new PS and trafos.
Cheers!
Russ
Attachments
With the same voltage on the primaries? Hook them up at the same time and check. Your line could have sagged when the fridge, heat... came on.
I checked them one after the other and did it several times in a row and ended up with the same results.
traw said:they came with the few i bought, already attached and bolt
Ditto.
Also, I replaced the battery in my DMM and the secondaries read a bit higher now, much more like I would expect.
Cheers!
Russ
No more Plitrons but,
Heatsinks:
http://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=11880&HS=1
Heatsinks:
http://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=11880&HS=1
Re: I need lower voltage!
Hmmmm, well one way to get it close would be to roll your own rectifier board and use two diodes in series for each diode position on the bridge.
FWIW I have a OPA549 amp that I have run with 31V rails without issues, but YMMV. It is of course beyond the 60V max Vs(max), but only by 2V.
Or you could build a simple regulator and get it down to 25V or so.
Good luck
Cheers!
Russ
jaudio said:I plan to use these transformer for 2 OPA549 bridged parallel amp with 8 chip in each amp. I need to lower the voltage to 28volts. What is the best way to lower the voltage?
Hmmmm, well one way to get it close would be to roll your own rectifier board and use two diodes in series for each diode position on the bridge.
FWIW I have a OPA549 amp that I have run with 31V rails without issues, but YMMV. It is of course beyond the 60V max Vs(max), but only by 2V.
Or you could build a simple regulator and get it down to 25V or so.
Good luck
Cheers!
Russ
delay circuit
With a few more pieces(resistor,fuses and bridge),would these make a good soft start circuit?
http://www.goldmine-elec-products.com/prodinfo.asp?number=G9651
http://www.goldmine-elec-products.com/prodinfo.asp?number=G16041
If so, would 4 seconds be a long enough delay?
With a few more pieces(resistor,fuses and bridge),would these make a good soft start circuit?
http://www.goldmine-elec-products.com/prodinfo.asp?number=G9651
http://www.goldmine-elec-products.com/prodinfo.asp?number=G16041
If so, would 4 seconds be a long enough delay?
Re: delay circuit
Sure 4 seconds is pleny long enough...if you want to start a fire!!!!
You really only need a short delay of a few ms running the mains through a properly sized power resistor to limit the inrush current, then switch on the relay to bypass the resistor. After 4 seconds at mains voltage your resistor would get hot....really hot! Check out Rod Elliots site and look at P39 http://sound.westhost.com/project39.htm Rod presents several approaches to adding a soft start and also goes through a method to calculate the current limiting resistor.
The relays you are looking at could work if you don't use the auxilliary transformer method. I would recomend something in the 12V to 24V range.
Sure 4 seconds is pleny long enough...if you want to start a fire!!!!
You really only need a short delay of a few ms running the mains through a properly sized power resistor to limit the inrush current, then switch on the relay to bypass the resistor. After 4 seconds at mains voltage your resistor would get hot....really hot! Check out Rod Elliots site and look at P39 http://sound.westhost.com/project39.htm Rod presents several approaches to adding a soft start and also goes through a method to calculate the current limiting resistor.
The relays you are looking at could work if you don't use the auxilliary transformer method. I would recomend something in the 12V to 24V range.
jaudio said:With a few more pieces(resistor,fuses and bridge),would these make a good soft start circuit?
http://www.goldmine-elec-products.com/prodinfo.asp?number=G9651
http://www.goldmine-elec-products.com/prodinfo.asp?number=G16041
If so, would 4 seconds be a long enough delay?
Gcollier
Thanks!
You save me alot of trouble.
mauropenasa has one with no transistors http://www.webalice.it/mauro.penasa/index.html
Thanks!
You save me alot of trouble.
mauropenasa has one with no transistors http://www.webalice.it/mauro.penasa/index.html
No problem...I would hate to see anybody blow something up...unless they were actually trying to
I actually just finished etching a board for the Rod Elliot design that uses the opamp. I have a 750VA Plitron that always manages to blow the breaker in my electrical panel. The soft start should help prevent this. I believe that Peranders also has a design you can look at.
G.
I actually just finished etching a board for the Rod Elliot design that uses the opamp. I have a 750VA Plitron that always manages to blow the breaker in my electrical panel. The soft start should help prevent this. I believe that Peranders also has a design you can look at.
G.
jaudio said:Gcollier
Thanks!
You save me alot of trouble.
mauropenasa has one with no transistors http://www.webalice.it/mauro.penasa/index.html
Yup, love those smilies!
impsick said:Gcollier, funny stuff man, i got a kick out of your last 2 replys.
i love running into a few laughs on here. and the smilies totally express the mood.
oh and your signiture thing is a crack up too. i saw that a few days ago.
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