Pioneer's SA500 Blowing protection fuse
#77
The out of focus effect is just a reduced size image, click on the image and you will see the full size one.ah that hasn't worked image out of focus
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#78
Using a choke is all very well but so far the currents quoted are just the quiescent idling, when the amplifier's are driving speakers to any decent kind of power they will be pulling AMPERES.... which will all have to come from the charge on the last supply cap, and then replaced, through a choke ~ it will have to be a high current one then
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#79
Ha Well it was just an idea to be a bit different high current sounds expensive maybe better to just use new 30volt TX with good diodes and double up on the capacitance
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#80
Or, but more complicated, could be a 2x18VAC (36VAC) so can use a Voltage regulator churning out 42V DC.
Bu-ut, means reservoir will have to be rated for 63V or higher.
Bu-ut, means reservoir will have to be rated for 63V or higher.
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#81
Well now looking to build a regulated single rail x2 psu Supply for the pioneer SA 500 And a Preamp kinda based on the naim hi capMike H wrote:Or, but more complicated, could be a 2x18VAC (36VAC) so can use a Voltage regulator churning out 42V DC.
Bu-ut, means reservoir will have to be rated for 63V or higher.
Psu Pre amp requires 30V and the amp requires 42v
Parts I have to hand are an 18-0-18-0 volt 300VA plus 10.000uf 63v x2 and three LM338K 1.5 to 32 volts 5 amp regulators TO 3 case types plus heat sinks would anyone care to come up with a suitably circuit in spice with parts list
pioneer SA500 Sch only the power amps is being used
thanks
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#83
Well my main system is solid state so want a good PSU to run a clone Naim 32.5 single ended pre amp and also to run the pioneer SA 500 Singe ended push pull amp so a clone version of the naim Hi cap psu is the way to go with this I thinkGreg wrote:Now why would you want to do that?colin.hepburn wrote:....................And a Preamp kinda based on the naim hi cap
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#85
Hi GregGreg wrote:OK, if you like what the Naim does, so be it. Sorry, when it comes to anything Naim, I'm a total sceptic
I'd be interested in your views on why you are a total sceptic about naim gear I have read that some don't like the naim stuff
I have the naim clone pre amp well will have when it arrives it was cheap of ebay so thought I would just try it
The naim hi cap Psu clone seems like a logical way of running both the pre amp and my SA500 pioneer which has a vibrating Transformer which i will be changing
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#86
Colin, how's the EL34 amp coming along.
When that gets going you will want to forget about sand amps.
When that gets going you will want to forget about sand amps.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
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#87
It's only a power supply Greg
Oh what a coincidence
This is a single-sided supply I presume? By which I mean, just ground 0V, a plus 30V and a plus 42V?
If so could have separate bridge rectifier cap & reg for each power amp.
Can look into it shortly
Well would you believe it just so happens I've got a LM338 model.colin.hepburn wrote:Psu Pre amp requires 30V and the amp requires 42v.
Parts I have to hand are an 18-0-18-0 volt 300VA plus 10.000uf 63v x2 and three LM338K 1.5 to 32 volts 5 amp regulators TO 3 case types plus heat sinks would anyone care to come up with a suitably circuit in spice with parts list
Oh what a coincidence
This is a single-sided supply I presume? By which I mean, just ground 0V, a plus 30V and a plus 42V?
If so could have separate bridge rectifier cap & reg for each power amp.
Can look into it shortly
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
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#88
Second question ~ originally the 30V pre-amp part is just taken off the main 42V rail via a 1.8k resistor, do you still want it like that or have it with its own separate regulator?
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
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#89
Hi MikeMike H wrote:Second question ~ originally the 30V pre-amp part is just taken off the main 42V rail via a 1.8k resistor, do you still want it like that or have it with its own separate regulator?
Yep single rail ground 0V, plus 30V and a plus 42V adjustably
It's a different pre amp it is in fact a naim clone 42.5 needs its own 30 volt reg psu and the amp need its own reg feed 42 volts but which can be reverse back to unregulated off the same psu if it changes the sound in the wrong way ???
Parts I got
18-0-18-0 @330VA
10.000uf@63voltsX2
Three LM338KX3 plus heat sinks
PS may be good to have two separate reg 30v supplies for the pre amp it thats possible see pre sch
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#90
Yep can do, need to get on with finishing some web pages first then can have a look
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."