transformers in parallel

[Phil Allison]

"Jamie"

Bad idea,,..
The diodes in the rectifier will not allow for even load distribution.

** Course they will - long as the transformers have the same voltage on
each secondary.

You may even have a bridge sitting there doing nothing while another is
doing all the work and over loading if self along with the single Xformer
it's connected to.

** Take a big error in the secondary voltages to cause that.

Please take good advise and combined all the xformers in parallel into a
single bridge rated for the combined load.

** What a fucking moron you are - Jamie.

You have just assumed that the transformers are not identical - THEN you
say to connect them in parallel is best.

Got a clue what that results in - dickwad ?

Massive current flow from one to another.

Then the smoke gets out.

You bullshitting ASS !



....... Phil

 

[Phil Allison]

"Jamie"

Phil Allison wrote:

Bad idea,,..
The diodes in the rectifier will not allow for even load distribution.


** Course they will - long as the transformers have the same voltage on
each secondary.

Incorrect!.

** You are a stupid ASS - Jaimie.

Diodes must be matched for that to happen even if the xformers were
perfectly matched.

** That is total BOLLOCKS - Jamie.

You are a stupid ASS - Jaimie.

And it's a fat chance that either will happen.

** There is every chance that BOTH would happen.

You stupid, lying ASS.

and if you were following the thread, all xformers are the same part #.

** Irrelevant what the part number is - you pathetic fuckwit.

You may even have a bridge sitting there doing nothing while another is
doing all the work and over loading if self along with the single Xformer
it's connected to.


** Take a big error in the secondary voltages to cause that.

** Lack of reply noted.

You are a stupid LYING ASS Jaimie.

If you knew anything at all, it was stated that all xformers were the
same part #. still does not mean they will perform equally. and yes
they can connect in parallel seeing they are the same type and the
little miss balance is not going to cause issues like bridges/diodes.

** That is total *** BOLLOCKS *** - Jaimie.

Where do you get these IDIOT idea from ??

Do the maths, stop your dumb guessing.


You are a pathetic, LYING stupid ASS Jaimie.

You are a criminal liar and a bullshitting ASS !




...... Phil

 

[Jamie]

Phil Allison wrote:

"Jamie"

Bad idea,,..
The diodes in the rectifier will not allow for even load distribution.



** Course they will - long as the transformers have the same voltage on
each secondary.
Incorrect!.

Diodes must be matched for that to happen even if the xformers were
perfectly matched.. And it's a fat chance that either will happen.
and if you were following the thread, all xformers are the same part #.

You may even have a bridge sitting there doing nothing while another is
doing all the work and over loading if self along with the single Xformer
it's connected to.



** Take a big error in the secondary voltages to cause that.



Please take good advise and combined all the xformers in parallel into a
single bridge rated for the combined load.



** What a fucking moron you are - Jamie.

You have just assumed that the transformers are not identical - THEN you
say to connect them in parallel is best.

Got a clue what that results in - dickwad ?

And as I said before.
If you knew anything at all, it was stated that all xformers were the
same part #. still does not mean they will perform equally. and yes
they can connect in parallel seeing they are the same type and the
little miss balance is not going to cause issues like bridges/diodes.

Pull your dick out of your ass if you have one.. This is obviously
beyond you .

Massive current flow from one to another.

Then the smoke gets out.

You bullshitting ASS !



...... Phil

Read Below Please, it suits you.

"Daily Thought:

SOME PEOPLE ARE LIKE SLINKIES. NOT REALLY GOOD FOR ANYTHING BUT
THEY BRING A SMILE TO YOUR FACE WHEN PUSHED DOWN THE STAIRS LIKE "PHIL"
FOR EXAMPLE.
http://webpages.charter.net/jamie_5"

 

[John Fields]

Jamie wrote:

Diodes must be matched for that to happen even if the xformers were
perfectly matched.

Phil Allison wrote:

** That is total BOLLOCKS - Jamie.

You are a stupid ASS - Jaimie.

---
Phil:

news:qatuu3prg7k4mcgqgdtq5r72k5lbl9dk3f@4ax.com

JF

 

[Ray]

To phase the transformers, connect them together one at a time and apply
voltage

If you connect them correctly there will be No change in voltage, when you
add a transformer (only in current capacity) Not in a voltage doubling as
stated above,

If you add one in the wrong direction, the voltages will cancel, and there
should be close to Zero volts.
<root114@gmail.com> wrote in message
news:3dfd08d2-598e-4492-ab90-b27719455d0d@s37g2000prg.googlegroups.com...
On 3ÔÂ29ČŐ, ÉĎÎç7Ęą41ˇÖ, mrdarr...@gmail.com wrote:

Let's say I've got a transformer, 110VAC primary, 24V secondary, 1A.

Let's say I've got 4 of them actually, same type, same manufacturer,
and want to wire them in parallel so I get 4A out, 24V.

Is this a bad idea?

Do I have to worry about connecting the outputs "in phase", or does it
matter?

I plan to rectify and filter the AC to get DC.

I suppose I could buy 4 bridge rectifiers and 4 filter caps to get the
DC out, but this gets expensive.

Thanks,

Michael

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wholesaler & drop-shipper: seriouswholesale. com

 

[Phil Allison]

"Ray from planet Ratbag "


** Another top posting dung head.

To phase the transformers, connect them together one at a time and apply
voltage

** Madness.

If you connect them correctly there will be No change in voltage, when
you add a transformer (only in current capacity) Not in a voltage doubling
as stated above,

If you add one in the wrong direction, the voltages will cancel, and there
should be close to Zero volts.

** Plus crackling noises and smoke in about 10 seconds.

100% stupid.

Never do it.



...... Phil

 

[Paul E. Schoen]

"Ray" <argyle1nospams@hotmail.com> wrote in message
newscYHj.141231$pM4.82648@pd7urf1no...
[deleted spam]

To phase the transformers, connect them together one at a time and apply
voltage

If you connect them correctly there will be No change in voltage, when
you add a transformer (only in current capacity) Not in a voltage
doubling as stated above,

If you add one in the wrong direction, the voltages will cancel, and
there should be close to Zero volts.

Why did you reply to spam?

Paul

 

[Phil Allison]

"Paul E. Schoen"
"Ray"

Why did you reply to spam?

** Same reason dogs piss on lamp poles.



....... Phil

 

[James Beck]

In article <5617e3c9-b9e9-42ec-80b8-c76d3b332631
@d4g2000prg.googlegroups.com>, mrdarrett@gmail.com says...

Let's say I've got a transformer, 110VAC primary, 24V secondary, 1A.

Let's say I've got 4 of them actually, same type, same manufacturer,
and want to wire them in parallel so I get 4A out, 24V.

Is this a bad idea?

Do I have to worry about connecting the outputs "in phase", or does it
matter?

I plan to rectify and filter the AC to get DC.

I suppose I could buy 4 bridge rectifiers and 4 filter caps to get the
DC out, but this gets expensive.

Thanks,

Michael

It is easy enough to figure out the phasing with a basic meter.

If you connect the secondaries of two of your transformers in series and
measure the voltage on the outside two legs, you should get double the
voltage if they are in phase and almost nothing if they aren't. You can
then move the wires to put them in parallel.
Like this

Connections :
1---------->
2-|
3-|
4---------->

2 * V on 1 and 4 means you can then connect 3 to 1 and 4 to 2 and get
double the I. Obviously YOU will need to mark the wires as you discover
what is what. I would use one transformer as a base and mark all the
rest to match it. Make sure to mark and track the primaries too! In
act do that first. Just any old AC1 and AC2 will do, you will then use
the secondaries to match the phasing.

Jim

 

On Mar 31, 6:46 am, James Beck <j...@reallykillersystems.com> wrote:

In article <5617e3c9-b9e9-42ec-80b8-c76d3b332631
@d4g2000prg.googlegroups.com>, mrdarr...@gmail.com says...

Let's say I've got a transformer, 110VAC primary, 24V secondary, 1A.

Let's say I've got 4 of them actually, same type, same manufacturer,
and want to wire them in parallel so I get 4A out, 24V.

Is this a bad idea?

Do I have to worry about connecting the outputs "in phase", or does it
matter?

I plan to rectify and filter the AC to get DC.

I suppose I could buy 4 bridge rectifiers and 4 filter caps to get the
DC out, but this gets expensive.

Thanks,

Michael

It is easy enough to figure out the phasing with a basic meter.
If you connect the secondaries of two of your transformers in series and
measure the voltage on the outside two legs, you should get double the
voltage if they are in phase and almost nothing if they aren't. You can
then move the wires to put them in parallel.
Like this

Connections :
1----------
2-|
3-|
4----------

2 * V on 1 and 4 means you can then connect 3 to 1 and 4 to 2 and get
double the I. Obviously YOU will need to mark the wires as you discover
what is what. I would use one transformer as a base and mark all the
rest to match it. Make sure to mark and track the primaries too! In
act do that first. Just any old AC1 and AC2 will do, you will then use
the secondaries to match the phasing.

Jim

Thanks for the replies, y'all. Looks like I was outbid for the
transformers anyway...
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180226894560&ssPageName=ADME:B:EOIBUAA:US:1123

I thought no one would raise the bid much above $6.

Thanks anyway. Learned a lot in this thread.

Michael

 

[Paul E. Schoen]

<mrdarrett@gmail.com> wrote in message
news:7b0ddbd1-00a6-4c5b-9c21-31e2bde23133@i29g2000prf.googlegroups.com...

On Mar 31, 6:46 am, James Beck <j...@reallykillersystems.com> wrote:
In article <5617e3c9-b9e9-42ec-80b8-c76d3b332631
@d4g2000prg.googlegroups.com>, mrdarr...@gmail.com says...

Let's say I've got a transformer, 110VAC primary, 24V secondary, 1A.

Let's say I've got 4 of them actually, same type, same manufacturer,
and want to wire them in parallel so I get 4A out, 24V.

Is this a bad idea?

Do I have to worry about connecting the outputs "in phase", or does it
matter?

I plan to rectify and filter the AC to get DC.

I suppose I could buy 4 bridge rectifiers and 4 filter caps to get the
DC out, but this gets expensive.

Thanks,

Michael

It is easy enough to figure out the phasing with a basic meter.
If you connect the secondaries of two of your transformers in series and
measure the voltage on the outside two legs, you should get double the
voltage if they are in phase and almost nothing if they aren't. You can
then move the wires to put them in parallel.
Like this

Connections :
1----------
2-|
3-|
4----------

2 * V on 1 and 4 means you can then connect 3 to 1 and 4 to 2 and get
double the I. Obviously YOU will need to mark the wires as you discover
what is what. I would use one transformer as a base and mark all the
rest to match it. Make sure to mark and track the primaries too! In
act do that first. Just any old AC1 and AC2 will do, you will then use
the secondaries to match the phasing.

Jim



Thanks for the replies, y'all. Looks like I was outbid for the
transformers anyway...
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180226894560&ssPageName=ADME:B:EOIBUAA:US:1123

I thought no one would raise the bid much above $6.

Thanks anyway. Learned a lot in this thread.

Michael

Probably just as well you lost that bid. It would have been a very
cumbersome and inefficient way to get the power supply you need on the
cheap. But if you really want to do it that way, I'll give you a full flat
rate box of transformers equivalent to Signal 241-6-16, which are 16 VCT at
2A. Just send me $10 by PayPal and I'll send you as many as will fit in the
box. I have at least 100 pieces surplus. They are a little rusty but work
fine. You can hook them up FWCT and get about 10-12 VDC at 2A from each,
and you can add them up in series to get any voltage you want. I'll also
throw in a bag of 100 1N4004 diodes. Same offer for anyone else. I need to
get rid of them, along with about 1/2 ton of other parts. Some are listed
on www.pstech-inc.com.

But I still wonder why you are trying so many different approaches. I gave
you links to some good deals on transformers and switching supplies. Why
don't you buy one of these switching supplies from this guy:
http://stores.ebay.com/semielectric. He also has some audio amp ICs, PCBs
for same, and other cool stuff.

You should have been at the HamFest in Timonium this past weekend. Some of
the vendors had nice switching supplies, linear supplies, and transformers
that would work for your needs, for only a few dollars, and trash cans full
of freebies that were being hauled to the dump with a front end loader.
It's a shame what gets thrown out, but the expense to advertise on eBay and
then ship especially heavy stuff is just prohibitive. And now it costs a
lot for these guys to load down their vans and drive 100-200 miles to sell
$50 of stuff in a day.

Two years ago I bought a 5 HP motor-generator set designed to teach motor
fundamantals, and they can be wired in various ways. They were about 200 lb
each, and I bought them for $30 each. If there is a HamFest near you,
that's the place to go for bargains, and also to meet other people who have
solid experience and/or wild and crazy ideas. Find your most local one at:
http://www.arrl.org/hamfests.html.

Paul

 

On Mar 31, 10:28 pm, "Paul E. Schoen" <pst...@smart.net> wrote:

mrdarr...@gmail.com> wrote in message

news:7b0ddbd1-00a6-4c5b-9c21-31e2bde23133@i29g2000prf.googlegroups.com...



On Mar 31, 6:46 am, James Beck <j...@reallykillersystems.com> wrote:
In article <5617e3c9-b9e9-42ec-80b8-c76d3b332631
@d4g2000prg.googlegroups.com>, mrdarr...@gmail.com says...

Let's say I've got a transformer, 110VAC primary, 24V secondary, 1A.

Let's say I've got 4 of them actually, same type, same manufacturer,
and want to wire them in parallel so I get 4A out, 24V.

Is this a bad idea?

Do I have to worry about connecting the outputs "in phase", or does it
matter?

I plan to rectify and filter the AC to get DC.

I suppose I could buy 4 bridge rectifiers and 4 filter caps to get the
DC out, but this gets expensive.

Thanks,

Michael

It is easy enough to figure out the phasing with a basic meter.
If you connect the secondaries of two of your transformers in series and
measure the voltage on the outside two legs, you should get double the
voltage if they are in phase and almost nothing if they aren't. You can
then move the wires to put them in parallel.
Like this

Connections :
1----------
2-|
3-|
4----------

2 * V on 1 and 4 means you can then connect 3 to 1 and 4 to 2 and get
double the I. Obviously YOU will need to mark the wires as you discover
what is what. I would use one transformer as a base and mark all the
rest to match it. Make sure to mark and track the primaries too! In
act do that first. Just any old AC1 and AC2 will do, you will then use
the secondaries to match the phasing.

Jim

Thanks for the replies, y'all. Looks like I was outbid for the
transformers anyway...
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180226894560&ssPag...

I thought no one would raise the bid much above $6.

Thanks anyway. Learned a lot in this thread.

Michael

Probably just as well you lost that bid. It would have been a very
cumbersome and inefficient way to get the power supply you need on the
cheap. But if you really want to do it that way, I'll give you a full flat
rate box of transformers equivalent to Signal 241-6-16, which are 16 VCT at
2A. Just send me $10 by PayPal and I'll send you as many as will fit in the
box. I have at least 100 pieces surplus. They are a little rusty but work
fine. You can hook them up FWCT and get about 10-12 VDC at 2A from each,
and you can add them up in series to get any voltage you want. I'll also
throw in a bag of 100 1N4004 diodes. Same offer for anyone else. I need to
get rid of them, along with about 1/2 ton of other parts. Some are listed
onwww.pstech-inc.com.

$10 by PayPal, shipping included in the price? Will think about
it... 16VCT means two 8V, right? or 16+16=32?

But I still wonder why you are trying so many different approaches. I gave
you links to some good deals on transformers and switching supplies. Why
don't you buy one of these switching supplies from this guy:http://stores.ebay.com/semielectric. He also has some audio amp ICs, PCBs
for same, and other cool stuff.

Yes, I noticed one in particular - the 24V at, what, 8A or so, I
forget... was a very good deal... shipping was kind of high though...
then I noticed the eBay one...

Since I need -28-0-+28V, I'm wondering if two switchers, 0-24VDC, are
NOT the way to go... some mentioned stability problems with two AT
power supplies in series... which are underpowered, by the way (at
least the ones I have, around 4A@12V)

Pretty much, since this is a hobby project, I'm going as cheap as I
can make it. Otherwise, might as well just hop over to Circuit City
and buy the factory-made deal... still have to visit the landfill,
maybe there are some neat deals there... I never made a switcher
before... the SG3525 sounds interesting.. the two Linear Technology
chips you proposed sound kind of pricey...

Plus, I never like to build a circuit I've never seen before without
understanding it, or getting feedback from experts. That's why I
asked so many questions about the redcircuits.com amplifiers. Don't
take it personally. ;-)

You should have been at the HamFest in Timonium this past weekend. Some of
the vendors had nice switching supplies, linear supplies, and transformers
that would work for your needs, for only a few dollars, and trash cans full
of freebies that were being hauled to the dump with a front end loader.
It's a shame what gets thrown out, but the expense to advertise on eBay and
then ship especially heavy stuff is just prohibitive. And now it costs a
lot for these guys to load down their vans and drive 100-200 miles to sell
$50 of stuff in a day.

Two years ago I bought a 5 HP motor-generator set designed to teach motor
fundamantals, and they can be wired in various ways. They were about 200 lb
each, and I bought them for $30 each. If there is a HamFest near you,
that's the place to go for bargains, and also to meet other people who have
solid experience and/or wild and crazy ideas. Find your most local one at:http://www.arrl.org/hamfests.html.

Paul

Thanks! I hadn't realized there was such waste...

Michael

 

On Mar 31, 10:28 pm, "Paul E. Schoen" <pst...@smart.net> wrote:

mrdarr...@gmail.com> wrote in message

news:7b0ddbd1-00a6-4c5b-9c21-31e2bde23133@i29g2000prf.googlegroups.com...



On Mar 31, 6:46 am, James Beck <j...@reallykillersystems.com> wrote:
In article <5617e3c9-b9e9-42ec-80b8-c76d3b332631
@d4g2000prg.googlegroups.com>, mrdarr...@gmail.com says...

Let's say I've got a transformer, 110VAC primary, 24V secondary, 1A.

Let's say I've got 4 of them actually, same type, same manufacturer,
and want to wire them in parallel so I get 4A out, 24V.

Is this a bad idea?

Do I have to worry about connecting the outputs "in phase", or does it
matter?

I plan to rectify and filter the AC to get DC.

I suppose I could buy 4 bridge rectifiers and 4 filter caps to get the
DC out, but this gets expensive.

Thanks,

Michael

It is easy enough to figure out the phasing with a basic meter.
If you connect the secondaries of two of your transformers in series and
measure the voltage on the outside two legs, you should get double the
voltage if they are in phase and almost nothing if they aren't. You can
then move the wires to put them in parallel.
Like this

Connections :
1----------
2-|
3-|
4----------

2 * V on 1 and 4 means you can then connect 3 to 1 and 4 to 2 and get
double the I. Obviously YOU will need to mark the wires as you discover
what is what. I would use one transformer as a base and mark all the
rest to match it. Make sure to mark and track the primaries too! In
act do that first. Just any old AC1 and AC2 will do, you will then use
the secondaries to match the phasing.

Jim

Thanks for the replies, y'all. Looks like I was outbid for the
transformers anyway...
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180226894560&ssPag...

I thought no one would raise the bid much above $6.

Thanks anyway. Learned a lot in this thread.

Michael

Probably just as well you lost that bid. It would have been a very
cumbersome and inefficient way to get the power supply you need on the
cheap. But if you really want to do it that way, I'll give you a full flat
rate box of transformers equivalent to Signal 241-6-16, which are 16 VCT at
2A. Just send me $10 by PayPal and I'll send you as many as will fit in the
box. I have at least 100 pieces surplus. They are a little rusty but work
fine. You can hook them up FWCT and get about 10-12 VDC at 2A from each,
and you can add them up in series to get any voltage you want. I'll also
throw in a bag of 100 1N4004 diodes. Same offer for anyone else. I need to
get rid of them, along with about 1/2 ton of other parts. Some are listed
onwww.pstech-inc.com.

But I still wonder why you are trying so many different approaches. I gave
you links to some good deals on transformers and switching supplies. Why
don't you buy one of these switching supplies from this guy:http://stores.ebay.com/semielectric. He also has some audio amp ICs, PCBs
for same, and other cool stuff.

You should have been at the HamFest in Timonium this past weekend. Some of
the vendors had nice switching supplies, linear supplies, and transformers
that would work for your needs, for only a few dollars, and trash cans full
of freebies that were being hauled to the dump with a front end loader.
It's a shame what gets thrown out, but the expense to advertise on eBay and
then ship especially heavy stuff is just prohibitive. And now it costs a
lot for these guys to load down their vans and drive 100-200 miles to sell
$50 of stuff in a day.

Two years ago I bought a 5 HP motor-generator set designed to teach motor
fundamantals, and they can be wired in various ways. They were about 200 lb
each, and I bought them for $30 each. If there is a HamFest near you,
that's the place to go for bargains, and also to meet other people who have
solid experience and/or wild and crazy ideas. Find your most local one at:http://www.arrl.org/hamfests.html.

Paul

Wow, May 18, Rancho Cordova? That's right in my backyard... thanks!

 

[Paul E. Schoen]

<mrdarrett@gmail.com> wrote in message
news:c5b88bd1-a2e4-4fe6-bb2a-7ee687d30aab@d21g2000prf.googlegroups.com...

On Mar 31, 10:28 pm, "Paul E. Schoen" <pst...@smart.net> wrote:

Probably just as well you lost that bid. It would have been a very
cumbersome and inefficient way to get the power supply you need on the
cheap. But if you really want to do it that way, I'll give you a full
flat
rate box of transformers equivalent to Signal 241-6-16, which are 16 VCT
at
2A. Just send me $10 by PayPal and I'll send you as many as will fit in
the
box. I have at least 100 pieces surplus. They are a little rusty but
work
fine. You can hook them up FWCT and get about 10-12 VDC at 2A from each,
and you can add them up in series to get any voltage you want. I'll also
throw in a bag of 100 1N4004 diodes. Same offer for anyone else. I need
to
get rid of them, along with about 1/2 ton of other parts. Some are
listed
onwww.pstech-inc.com.


$10 by PayPal, shipping included in the price? Will think about
it... 16VCT means two 8V, right? or 16+16=32?

Yes, but the two windings are connected as a center tap, 8-0-8. They are
virtually identical to the Hammond 187D16 described on
http://www.hammondmfg.com/186_187.htm. I have some with dual primaries. I
use them with a FWCT rectifier to get about 10-12 VDC (which I regulate to
5 VDC), and then I use voltage doublers to get +/- 25 VDC which I regulate
to +/- 15 VDC. I don't need that much power, but I got a few hundred of
these as surplus, and I had plenty of room. They are used in my Ortmaster
product. See links in www.pstech-inc.com.

A FWB would give you about 20-24 VDC at 1 amp (maybe 1.5).

But I still wonder why you are trying so many different approaches. I
gave
you links to some good deals on transformers and switching supplies. Why
don't you buy one of these switching supplies from this guy:
http://stores.ebay.com/semielectric.
He also has some audio amp ICs, PCBs
for same, and other cool stuff.


Yes, I noticed one in particular - the 24V at, what, 8A or so, I
forget... was a very good deal... shipping was kind of high though...
then I noticed the eBay one...

Since I need -28-0-+28V, I'm wondering if two switchers, 0-24VDC, are
NOT the way to go... some mentioned stability problems with two AT
power supplies in series... which are underpowered, by the way (at
least the ones I have, around 4A@12V)

The eBay store I mentioned has a dual output switcher with +/- 43 VDC at 2
A, which is perfect for an amplifier that puts 100+ watts RMS into 8 ohms.
It's about $30 including shipping.

Pretty much, since this is a hobby project, I'm going as cheap as I
can make it. Otherwise, might as well just hop over to Circuit City
and buy the factory-made deal... still have to visit the landfill,
maybe there are some neat deals there... I never made a switcher
before... the SG3525 sounds interesting.. the two Linear Technology
chips you proposed sound kind of pricey...

Plus, I never like to build a circuit I've never seen before without
understanding it, or getting feedback from experts. That's why I
asked so many questions about the redcircuits.com amplifiers. Don't
take it personally. ;-)

Yes, you seem eager to learn and try things. Maybe because for most of
these projects, I've already been there, done that, and I see no need to do
things the hard way. I use LTSpice to try new ideas, and then unless I have
a real need for the circuit, I just file it away for the future. I pretty
much know it will work. But sometimes I like to breadboard things, just to
make sure. There are usually surprises, especially with high frequency
switchers like the one I recently designed and made PC boards. Layout is
critical, and I expected about 92% efficiency, but could only get about
85%. And it's hard to make changes on a 1" x 2.5" board with mostly SMT
components.

You should have been at the HamFest in Timonium this past weekend. Some
of
the vendors had nice switching supplies, linear supplies, and
transformers
that would work for your needs, for only a few dollars, and trash cans
full
of freebies that were being hauled to the dump with a front end loader.
It's a shame what gets thrown out, but the expense to advertise on eBay
and
then ship especially heavy stuff is just prohibitive. And now it costs a
lot for these guys to load down their vans and drive 100-200 miles to
sell
$50 of stuff in a day.

Two years ago I bought a 5 HP motor-generator set designed to teach
motor
fundamantals, and they can be wired in various ways. They were about 200
lb
each, and I bought them for $30 each. If there is a HamFest near you,
that's the place to go for bargains, and also to meet other people who
have
solid experience and/or wild and crazy ideas. Find your most local one
at: http://www.arrl.org/hamfests.html.

Paul


Thanks! I hadn't realized there was such waste...

Michael