Positive rail looks OK
Negative rail, not OK but some 79xx regulators need a minimum load in order to work, and so if this -25 volts is with it "open" then try connecting a 1k as a load. If there was smoke then its definitely zapped.l
The bulb should go in series with the mains as a means of protection against overcurrent and shorts.
Negative rail, not OK but some 79xx regulators need a minimum load in order to work, and so if this -25 volts is with it "open" then try connecting a 1k as a load. If there was smoke then its definitely zapped.l
The bulb should go in series with the mains as a means of protection against overcurrent and shorts.
~ Update
Replaced both regulators for safety, definately connected right this time.
How exactly am I measuring?
I have smallish resistors across both pos to gnd and neg to gnd... is a bulb necessary?
I'm not switching anyhting on untill I know this arrangement is ok
The resistors are actually the ones I'll be using for suggested CRC.
Once I'm done measuring, where should the resistors go/ I'm guessing one per rail, between each cap.
Regarding rest of system; this is the last stage.
hopefully I've assembled the xo boards correctly and not melted any components - reading the instructions most parts can resist 5seconds of heat ... fingers crossed.
I'll prolly plug the xo into a pc sound card to measure response of each band .
Replaced both regulators for safety, definately connected right this time.
How exactly am I measuring?
I have smallish resistors across both pos to gnd and neg to gnd... is a bulb necessary?
I'm not switching anyhting on untill I know this arrangement is ok
The resistors are actually the ones I'll be using for suggested CRC.
Once I'm done measuring, where should the resistors go/ I'm guessing one per rail, between each cap.
Regarding rest of system; this is the last stage.
hopefully I've assembled the xo boards correctly and not melted any components - reading the instructions most parts can resist 5seconds of heat ... fingers crossed.
I'll prolly plug the xo into a pc sound card to measure response of each band .
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That arrangement sounds OK. The resistors are just a small load across each rail to pull a few milliamps... nothing more. Each rail should measure correctly and correspond to the regulator type fitted. The bulb stops excess current and can prevent further damage, but if nothings gone up in smoke then your OK.
The resistors were only to load the regulators during testing (in case they were of a type/brand that needed a minimum current draw). If the outputs are correct then all is OK and in any event, once connected to the opamps then they would fulfil the same function and draw current.
So if the output from the regs is OK then all is well.
So if the output from the regs is OK then all is well.
OK Well, there are probably differing views on this but my thoughts would be that if you really want this then it has to go on the input side of the regulator. To add anything resistive on the output side will destroy the regulation of the rails and raise the output impedance (they will dip and be modulated as varying load current is drawn). That said, its very application specific though...
Ideally you should do real measurements and identify problems (or areas to improve) rather than just adding something in the hope it might better. Measurement is the key.
Well, there are probably differing views on this but my thoughts would be that if you really want this then it has to go on the input side of the regulator. To add anything resistive on the output side will destroy the regulation of the rails and raise the output impedance (they will dip and be modulated as varying load current is drawn). That said, its very application specific though...Ideally you should do real measurements and identify problems (or areas to improve) rather than just adding something in the hope it might better. Measurement is the key.
Yes
but on the input side of the reg. So you have bridge rectifier > reservoir cap > resistor > filter cap > regulator.
Still not tested anything as of yet but,
The crossover & HPF circuits have "GND" screws/ connections.
I lumped these to the ground in the below drawing.
You're saying PSU common should terminate and not be joined to anything else (as it does in the drawing).(?)
Also, silver plugs used for HPF (below) have grounds, wasn't sure what to connect them to so I left them ungrounded ...
cheers for any pointers,
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I wish you would attach your pics.Still not tested anything as of yet but,
The crossover & HPF circuits have "GND" screws/ connections.
I lumped these to the ground in the below drawing.
You're saying PSU common should terminate and not be joined to anything else (as it does in the drawing).(?)
Also, silver plugs used for HPF (below) have grounds, wasn't sure what to connect them to so I left them ungrounded ...
cheers for any pointers,
The barrel of an RCA is the SIGNAL Return.
It must be connected to the Source and it must be connected to the Receiver.
Lots of people use the general word "ground" to mean lots of different things.
One of these uses is what we stand on !
That word causes endless confusion in electronics.
I have put the idea forward that we should be more specific in "WHICH" ground we mean, whenever we refer to "it".
There are few, to no takers.
I would like to go further and ban the "ground" word, whenever it is used alone, from this site.
That proposal probably has even even takers. I would be throwing handkerchiefs into the wind.
Be specific and the confusion disappears.
I have listed the specifics in the past, but folk either don't like being told what to do or think I am bonkers, maybe both.
The SIGNAL has to be connected by two wires. They BOTH connect to the source. The signal connection MUST form a CIRCUIT. What comes out of the Source MUST Return to the Source. There are no exceptions.
The two wires are signal flow and signal return. No confusion and no use of the word "ground" !!!!!!!!!!!!!!
One of these uses is what we stand on !
That word causes endless confusion in electronics.
I have put the idea forward that we should be more specific in "WHICH" ground we mean, whenever we refer to "it".
There are few, to no takers.
I would like to go further and ban the "ground" word, whenever it is used alone, from this site.
That proposal probably has even even takers. I would be throwing handkerchiefs into the wind.
Be specific and the confusion disappears.
I have listed the specifics in the past, but folk either don't like being told what to do or think I am bonkers, maybe both.
The SIGNAL has to be connected by two wires. They BOTH connect to the source. The signal connection MUST form a CIRCUIT. What comes out of the Source MUST Return to the Source. There are no exceptions.
The two wires are signal flow and signal return. No confusion and no use of the word "ground" !!!!!!!!!!!!!!
post57 diagram helps with the confusion.
It shows a Signal Input with an in arrow.
This is the Signal Flow.
The Signal Return has been omitted.
The Signal Output is shown with an out arrow.
The Signal Return has been omitted.
There are two ground symbols. These are connected to nothing. How much more confusing can the diagram get?
It shows a Signal Input with an in arrow.
This is the Signal Flow.
The Signal Return has been omitted.
The Signal Output is shown with an out arrow.
The Signal Return has been omitted.
There are two ground symbols. These are connected to nothing. How much more confusing can the diagram get?
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