[geoff]

Does anybody know the actual current drain of an RNC off the top of
their head ? I have the 9vac version, and I know it *says* 500mA on the
back.

I am putting together a single power supply for all 3 and don't want to
unnecessarily overdo the current . But I am not where they actually are
at the moment so am unable to test for myself.

cheers

geoff

[Mike Rivers[_2_]]

On 5/7/2017 11:17 PM, geoff wrote:
Does anybody know the actual current drain of an RNC off the top of
their head ? I have the 9vac version, and I know it *says* 500mA on the
back.

I am putting together a single power supply for all 3 and don't want to
unnecessarily overdo the current .

You can't overdo the current. Get a 1.5A transformer. Or if you really
want to cut the corners as tight as you can, e-mail
and ask the man who designed it.



--

For a good time, call http://mikeriversaudio.wordpress.com

[[email protected]]

On Monday, May 8, 2017 at 7:27:59 AM UTC-4, Mike Rivers wrote:
On 5/7/2017 11:17 PM, geoff wrote:
Does anybody know the actual current drain of an RNC off the top of
their head ? I have the 9vac version, and I know it *says* 500mA on the
back.

I am putting together a single power supply for all 3 and don't want to
unnecessarily overdo the current .

You can't overdo the current. Get a 1.5A transformer. Or if you really
want to cut the corners as tight as you can, e-mail
and ask the man who designed it.



--

For a good time, call http://mikeriversaudio.wordpress.com

1.5A 9VDC supply, $6.95!
http://www.ebay.com/sch/i.html?_nkw=9v+dc+power+supply

A lot cheaper than a POS HP CD writer!

Jack

[Mike Rivers[_2_]]

On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.



--

For a good time, call http://mikeriversaudio.wordpress.com

[[email protected]]

On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

Sorry, had no idea what he had, not like a RNC can't be the Republican National Convention!

Here you go, 18VAC CT....

http://www.ebay.com/itm/18V-9V-Trans...AOSwcLxYEgx 0

Jack



--

For a good time, call http://mikeriversaudio.wordpress.com

[Scott Dorsey]

In article , Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

I can't say offhand how the numbers work out, but I have two of them running
off a (10V at 1.2A) Triad FP10-1200 flatpack transformer, along with some
crossover electronics that probably take a hundred mA. The Triads are pretty
conservatively rated, they fit into a 1U case, but I think the 1.2A is the
largest one available.

If I was looking for 9 or 10 volts at 1.5A, I would look at the Amveco
(formerly Talema) toroids.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

On Monday, May 8, 2017 at 9:22:43 AM UTC-4, Scott Dorsey wrote:
In article , Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

I can't say offhand how the numbers work out, but I have two of them running
off a (10V at 1.2A) Triad FP10-1200 flatpack transformer, along with some
crossover electronics that probably take a hundred mA. The Triads are pretty
conservatively rated, they fit into a 1U case, but I think the 1.2A is the
largest one available.

If I was looking for 9 or 10 volts at 1.5A, I would look at the Amveco
(formerly Talema) toroids.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

I used to buy standard 12V Xfmrs, and removed secondary turns to whatever I needed. Costly to buy non-standard voltages, 18V CT makes more sense.

Jack

[Don Pearce[_3_]]

On Mon, 8 May 2017 06:34:38 -0700 (PDT), wrote:

On Monday, May 8, 2017 at 9:22:43 AM UTC-4, Scott Dorsey wrote:
In article , Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

I can't say offhand how the numbers work out, but I have two of them running
off a (10V at 1.2A) Triad FP10-1200 flatpack transformer, along with some
crossover electronics that probably take a hundred mA. The Triads are pretty
conservatively rated, they fit into a 1U case, but I think the 1.2A is the
largest one available.

If I was looking for 9 or 10 volts at 1.5A, I would look at the Amveco
(formerly Talema) toroids.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

I used to buy standard 12V Xfmrs, and removed secondary turns to whatever I needed. Costly to buy non-standard voltages, 18V CT makes more sense.

Jack

Switchers are dead cheap these days, and frankly they are pretty much
as clean as linears.

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[[email protected]]

On Monday, May 8, 2017 at 9:34:40 AM UTC-4, wrote:
On Monday, May 8, 2017 at 9:22:43 AM UTC-4, Scott Dorsey wrote:
In article , Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

I can't say offhand how the numbers work out, but I have two of them running
off a (10V at 1.2A) Triad FP10-1200 flatpack transformer, along with some
crossover electronics that probably take a hundred mA. The Triads are pretty
conservatively rated, they fit into a 1U case, but I think the 1.2A is the
largest one available.

If I was looking for 9 or 10 volts at 1.5A, I would look at the Amveco
(formerly Talema) toroids.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

I used to buy standard 12V Xfmrs, and removed secondary turns to whatever I needed. Costly to buy non-standard voltages, 18V CT makes more sense.

Jack

Now, you may ask, how do you know how many turns to remove.
Good question.
Plug in transformer, measure secondary voltage open circuit.
Fish a small wire through each window of the transformer, as (1) turn.
Plug in transformer and measure voltage of that one turn, that will give us volts per turn.
Say it measures 0.4 volts
Divide secondary winding by .4V and that tells us how many secondary turns.
Elementary after that.
A decent rule for transformers, square-root of kVA = Volts Per Turn

Jack

[[email protected]]

On Monday, May 8, 2017 at 9:48:31 AM UTC-4, Don Pearce wrote:
On Mon, 8 May 2017 06:34:38 -0700 (PDT), wrote:

On Monday, May 8, 2017 at 9:22:43 AM UTC-4, Scott Dorsey wrote:
In article , Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

I can't say offhand how the numbers work out, but I have two of them running
off a (10V at 1.2A) Triad FP10-1200 flatpack transformer, along with some
crossover electronics that probably take a hundred mA. The Triads are pretty
conservatively rated, they fit into a 1U case, but I think the 1.2A is the
largest one available.

If I was looking for 9 or 10 volts at 1.5A, I would look at the Amveco
(formerly Talema) toroids.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

I used to buy standard 12V Xfmrs, and removed secondary turns to whatever I needed. Costly to buy non-standard voltages, 18V CT makes more sense.

Jack

Switchers are dead cheap these days, and frankly they are pretty much
as clean as linears.

I'll admit that true, but I've seen more problems (failures) with switchers than linear.

Jack

d

---
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[Mike Rivers[_2_]]

On 5/8/2017 9:48 AM, Don Pearce wrote:
Switchers are dead cheap these days, and frankly they are pretty much
as clean as linears.

But, relative to the problem at hand here, all that's needed is a
transformer. There's a bridge rectifier inside the RNC (Really Nice
Compressor for those who don't know), and that feeds separate regulators
for the positive and negative voltages required by the internal workings.

Geoff asked for the right thing - a transformer. And since he was
planning on powering three units with it, one that he could mount in a
box is more appropriate for the job than a wall wart with a single
output cable.

--

For a good time, call http://mikeriversaudio.wordpress.com

[Scott Dorsey]

Don Pearce wrote:
On Mon, 8 May 2017 06:34:38 -0700 (PDT), wrote:
On Monday, May 8, 2017 at 9:22:43 AM UTC-4, Scott Dorsey wrote:
In article , Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

I can't say offhand how the numbers work out, but I have two of them running
off a (10V at 1.2A) Triad FP10-1200 flatpack transformer, along with some
crossover electronics that probably take a hundred mA. The Triads are pretty
conservatively rated, they fit into a 1U case, but I think the 1.2A is the
largest one available.

If I was looking for 9 or 10 volts at 1.5A, I would look at the Amveco
(formerly Talema) toroids.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

I used to buy standard 12V Xfmrs, and removed secondary turns to whatever I needed. Costly to buy non-standard voltages, 18V CT makes more sense.

Jack

Switchers are dead cheap these days, and frankly they are pretty much
as clean as linears.


Fortunately or unfortunately, the RNC uses a trick supply to generate +/-15V
from an unreferenced AC input. So it really does need 60 Hz going in.

I'm not big fan of switchers; it's possible to make them quiet, or reliable,
or cheap, but I am not sure you can do all three. But sometimes you need
density and there's no way around it.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

On Monday, May 8, 2017 at 11:19:42 AM UTC-4, Mike Rivers wrote:
On 5/8/2017 9:48 AM, Don Pearce wrote:
Switchers are dead cheap these days, and frankly they are pretty much
as clean as linears.

But, relative to the problem at hand here, all that's needed is a
transformer. There's a bridge rectifier inside the RNC (Really Nice
Compressor for those who don't know), and that feeds separate regulators
for the positive and negative voltages required by the internal workings.

Compressor? Brick-walled Geoff! :-)

Jack

Geoff asked for the right thing - a transformer. And since he was
planning on powering three units with it, one that he could mount in a
box is more appropriate for the job than a wall wart with a single
output cable.

--

For a good time, call http://mikeriversaudio.wordpress.com

[John Williamson]

On 08/05/2017 13:34, wrote:
On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

Sorry, had no idea what he had, not like a RNC can't be the Republican National Convention!

Here you go, 18VAC CT....

Still not reading the message, then. The OP was asking for a 9 volt
alternating current supply, you have offered a 9 volt direct current one
and an 18 volt alternating current, albeit with a centre tap, so you are
throwing away half the cost. Still, with luck, you may get there in the
end....


--
Tciao for Now!

John.

[[email protected]]

On Monday, May 8, 2017 at 4:01:39 PM UTC-4, John Williamson wrote:
On 08/05/2017 13:34, wrote:
On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.

Sorry, had no idea what he had, not like a RNC can't be the Republican National Convention!

Here you go, 18VAC CT....

Still not reading the message, then. The OP was asking for a 9 volt
alternating current supply, you have offered a 9 volt direct current one
and an 18 volt alternating current, albeit with a centre tap, so you are
throwing away half the cost. Still, with luck, you may get there in the
end....


--
Tciao for Now!

John.

Look, listen, read lips. You take wrapper off, untwist centertap, connect two windings in parallel for a whopping 9VAC at 6A!

Run nice and cool!

Jack

[geoff]

On 9/05/2017 7:09 AM, Gareth Magennis wrote:



9v AC "Wall Warts" are cheap and available. I buy a few a year.


Indeed.

Why I want to know the *actual* current requirement is that one
possibility is running all 3 off a single wall-wart, but not if real
current requirement is 1.5A, in which case I'll build a box with a
xformer. Ideally with isolated 9v windings.

FMR (as they state) are not great at checking and replying to their
email quickly.

geoff

[Mike Rivers[_2_]]

On 5/8/2017 6:23 PM, geoff wrote:
Why I want to know the *actual* current requirement is that one
possibility is running all 3 off a single wall-wart, but not if real
current requirement is 1.5A, in which case I'll build a box with a
xformer. Ideally with isolated 9v windings.

I'll bet that a transformer with three 9v secondaries is going to be
pretty hard to find. But I suspect that running them off the same
single-winding transformer isn't going to be a problem. The RNC inputs
and outputs are single-ended (unbalanced) so any two that connect to the
same piece of equipment, like two channels of a mixer, will have their
grounds tied together anyway.



--

For a good time, call http://mikeriversaudio.wordpress.com

[geoff]

On 9/05/2017 11:44 a.m., Gareth Magennis wrote:





I'm not sure you want to know the "actual" current requirements, but
rather the worst case sudden demand requirements that is not going to
crash the unit(s).
Particularly when several boot up on a single supply.


Gareth



Yep. That's part of 'actual'.

geoff

[[email protected]]

On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.



--

For a good time, call http://mikeriversaudio.wordpress.com

You know, you scream at me, but it's Geoff failing to tell what RNC he has!

"rear panel view shows 600mA"...
https://www.gearslutz.com/board/low-...er-supply.html

Not sure why people continue with electronic stuff [rather than digital], guess they like turning knobs!! Like a pacifier.

Jack :-)

[[email protected]]

On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
On 5/8/2017 8:01 AM, wrote:
1.5A 9VDC supply, $6.95!

RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.



--

For a good time, call http://mikeriversaudio.wordpress.com

Geoff dials: (01) 512 352 3290

Ring ring.
Hello, FMR Audio, may I help you?
I'd like to know average and max current draw for RNC blah, blah, blah...
Why certainly, it is blah, blah, blah.
Thank you, blah, *click*

Geez!

Jack

[Scott Dorsey]

Gareth Magennis wrote:
Nobody here is going to be able to, or be bothered to, measure that peak
demand though.

Lots of folks should be able to. I can do it with my Simpson 260, the
latest in current metering technology.

Asking on here what the current draw is under steady state conditions is not
going to help you choose your transformer.

When in doubt, always use a larger power supply than you ever think you will
need. Then use one size larger than that.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

On Monday, May 8, 2017 at 8:05:29 PM UTC-4, Scott Dorsey wrote:
Gareth Magennis wrote:
Nobody here is going to be able to, or be bothered to, measure that peak
demand though.

Lots of folks should be able to. I can do it with my Simpson 260, the
latest in current metering technology.

Asking on here what the current draw is under steady state conditions is not
going to help you choose your transformer.

When in doubt, always use a larger power supply than you ever think you will
need. Then use one size larger than that.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Scott does have one of the early 260's with pin, not banana jacks!

Jack

[[email protected]]

On Monday, May 8, 2017 at 8:05:29 PM UTC-4, Scott Dorsey wrote:
Gareth Magennis wrote:
Nobody here is going to be able to, or be bothered to, measure that peak
demand though.

Lots of folks should be able to. I can do it with my Simpson 260, the
latest in current metering technology.

Asking on here what the current draw is under steady state conditions is not
going to help you choose your transformer.

When in doubt, always use a larger power supply than you ever think you will
need. Then use one size larger than that.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Fluke multimeters can even record the Peak AC current!!

Jack

[Mike Rivers[_2_]]

On 5/8/2017 8:02 PM, Gareth Magennis wrote:
Nobody here is going to be able to, or be bothered to, measure that peak
demand though.

Asking on here what the current draw is under steady state conditions is
not going to help you choose your transformer.

This is so simple. The official power supply is 500 mA for one unit.
Three units all working as hard as they can will draw no more than 1.5
A. Get a transformer that's capable of at least 1.5 A, put it in a box,
make up cables to plug into each of your three RNCs, and Bob's your uncle.

Don't try to shave a couple of milliamps and not be sure.



--

For a good time, call http://mikeriversaudio.wordpress.com

[Trevor]

On 9/05/2017 6:01 AM, John Williamson wrote:
On 08/05/2017 13:34, wrote:
On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.


Here you go, 18VAC CT....

Still not reading the message, then. The OP was asking for a 9 volt
alternating current supply, you have offered a 9 volt direct current one
and an 18 volt alternating current, albeit with a centre tap, so you are
throwing away half the cost.


But to be fair, many CT transformers can easily be wired for parallel
windings giving half the voltage and twice the current.

Trevor.

[Trevor]

On 9/05/2017 10:55 AM, Mike Rivers wrote:
On 5/8/2017 8:02 PM, Gareth Magennis wrote:
Nobody here is going to be able to, or be bothered to, measure that peak
demand though.

Asking on here what the current draw is under steady state conditions is
not going to help you choose your transformer.

This is so simple. The official power supply is 500 mA for one unit.
Three units all working as hard as they can will draw no more than 1.5
A. Get a transformer that's capable of at least 1.5 A, put it in a box,
make up cables to plug into each of your three RNCs, and Bob's your uncle.



Right, but I bet his dilemma is whether he really needs a 2A transformer
or can get away with a 1A one. (1.5A not usually a stock size)
Personally I'd just go for 2A and be done with it, but that's me.

Trevor.

[John Williamson]

On 09/05/2017 05:32, Trevor wrote:
On 9/05/2017 6:01 AM, John Williamson wrote:
On 08/05/2017 13:34, wrote:
On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.


Here you go, 18VAC CT....

Still not reading the message, then. The OP was asking for a 9 volt
alternating current supply, you have offered a 9 volt direct current one
and an 18 volt alternating current, albeit with a centre tap, so you are
throwing away half the cost.


But to be fair, many CT transformers can easily be wired for parallel
windings giving half the voltage and twice the current.

If it is truly centre tapped, the outputs will be out of phase. Only 9+9
volt transformer with two isolated windings can do that.


--
Tciao for Now!

John.

[Don Pearce[_3_]]

On Tue, 9 May 2017 06:23:35 +0100, John Williamson
wrote:

On 09/05/2017 05:32, Trevor wrote:
On 9/05/2017 6:01 AM, John Williamson wrote:
On 08/05/2017 13:34, wrote:
On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.


Here you go, 18VAC CT....

Still not reading the message, then. The OP was asking for a 9 volt
alternating current supply, you have offered a 9 volt direct current one
and an 18 volt alternating current, albeit with a centre tap, so you are
throwing away half the cost.


But to be fair, many CT transformers can easily be wired for parallel
windings giving half the voltage and twice the current.

If it is truly centre tapped, the outputs will be out of phase. Only 9+9
volt transformer with two isolated windings can do that.

Once you unwind the centre tap connections from each other you have
two separate windings which can be connected in whatever phase you
choose.

d

---
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[John Williamson]

On 09/05/2017 07:17, Don Pearce wrote:
On Tue, 9 May 2017 06:23:35 +0100, John Williamson
wrote:

If it is truly centre tapped, the outputs will be out of phase. Only 9+9
volt transformer with two isolated windings can do that.

Once you unwind the centre tap connections from each other you have
two separate windings which can be connected in whatever phase you
choose.

True, but that's not exactly a straight out of the box solution. If you
want to go that far, I used to be able to get transformer kits, with the
HT winding safely shielded and instruction for the number of turns per
volt on the secondary. and room for more than one secondary winding, so
3 secondaries was within easy reach.


--
Tciao for Now!

John.

[Scott Dorsey]

In article , Trevor wrote:

But to be fair, many CT transformers can easily be wired for parallel
windings giving half the voltage and twice the current.

Those are "dual winding" transformers and not center-tapped ones. They are
very popular these days now that transformers aren't as large production items
as they once were and tend to be made on standardized bobbins and frames.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

On Tuesday, May 9, 2017 at 5:38:01 AM UTC-4, John Williamson wrote:
On 09/05/2017 07:17, Don Pearce wrote:
On Tue, 9 May 2017 06:23:35 +0100, John Williamson
wrote:

If it is truly centre tapped, the outputs will be out of phase. Only 9+9
volt transformer with two isolated windings can do that.

Once you unwind the centre tap connections from each other you have
two separate windings which can be connected in whatever phase you
choose.

True, but that's not exactly a straight out of the box solution. If you
want to go that far, I used to be able to get transformer kits, with the
HT winding safely shielded and instruction for the number of turns per
volt on the secondary. and room for more than one secondary winding, so
3 secondaries was within easy reach.


--
Tciao for Now!

John.

True, it requires a bit of work, but since the asking person exhausts time in usenet, I'm sure he has time avaible. Also, I have no clue where he resides. So, when asking Alternating Current questions, it's nice to know the frequency of the mains or service. While I'm sure most transformers are now designed for international use, when using a 60Hz transformer at 50Hz, you risk saturating the core.

Sure, I bet you can buy bobbins and EI (scrapless) laminations and magnet wire and design and wind your own! :-)

Jack

[[email protected]]

On Tuesday, May 9, 2017 at 12:33:06 AM UTC-4, Trevor wrote:
On 9/05/2017 6:01 AM, John Williamson wrote:
On 08/05/2017 13:34, wrote:
On Monday, May 8, 2017 at 8:16:07 AM UTC-4, Mike Rivers wrote:
RTFMessage! This is a DC power supply (about a hundred of 'em - you
could have linked to the one you thought was the right one). A DC power
supply won't power a device that expects an AC input, at least not with
considerable modification.


Here you go, 18VAC CT....

Still not reading the message, then. The OP was asking for a 9 volt
alternating current supply, you have offered a 9 volt direct current one
and an 18 volt alternating current, albeit with a centre tap, so you are
throwing away half the cost.


But to be fair, many CT transformers can easily be wired for parallel
windings giving half the voltage and twice the current.

I wouldn't go as far to say they equally share then same amount of current draw, since the windings themselves may be asymmetrical.

Jack


Trevor.

[geoff]

On 8/05/2017 3:17 PM, geoff wrote:
Does anybody know the actual current drain of an RNC off the top of
their head ? I have the 9vac version, and I know it *says* 500mA on the
back.

I am putting together a single power supply for all 3 and don't want to
unnecessarily overdo the current . But I am not where they actually are
at the moment so am unable to test for myself.

cheers

geoff



Heard back from Mark @ FMR.

350mA each with the disclaimers 'closer to' and 'in normal circumstances'.

So trying to power 3 off a 1A rated plug-pack daisy-chained would be
stretching things, so I'll go with the next-size-up transformer built
into a case option.

geoff

[[email protected]]

On Tuesday, May 9, 2017 at 4:15:05 PM UTC-4, geoff wrote:
On 8/05/2017 3:17 PM, geoff wrote:
Does anybody know the actual current drain of an RNC off the top of
their head ? I have the 9vac version, and I know it *says* 500mA on the
back.

I am putting together a single power supply for all 3 and don't want to
unnecessarily overdo the current . But I am not where they actually are
at the moment so am unable to test for myself.

cheers

geoff



Heard back from Mark @ FMR.

350mA each with the disclaimers 'closer to' and 'in normal circumstances'.

So trying to power 3 off a 1A rated plug-pack daisy-chained would be
stretching things, so I'll go with the next-size-up transformer built
into a case option.

But it is Music, not a stable load.

Jack

geoff

[Trevor]

On 9/05/2017 10:22 PM, Scott Dorsey wrote:
In article , Trevor wrote:

But to be fair, many CT transformers can easily be wired for parallel
windings giving half the voltage and twice the current.

Those are "dual winding" transformers and not center-tapped ones.

Yes, dual windings when the centre tap loop is removed. But ANY centre
tap transformer that has access to the winding where it is centre tap
looped can be cut and rewired just as I said. Not all, but "many" as I said.

Trevor.

[[email protected]]

On Tuesday, May 9, 2017 at 8:22:53 AM UTC-4, Scott Dorsey wrote:
In article , Trevor wrote:

But to be fair, many CT transformers can easily be wired for parallel
windings giving half the voltage and twice the current.

Those are "dual winding" transformers and not center-tapped ones.



True. They are known as Auto Transformers. Dual, Double Wound, same thing.

Jack

They are
very popular these days now that transformers aren't as large production items
as they once were and tend to be made on standardized bobbins and frames.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."