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From: bob haller on 19 Jan 2010 22:14
120 volt in, 35 volts out 1.2 amps I am having a hard time finding a
35 or 36 volts out transformer.
From: ehsjr on 19 Jan 2010 23:35
bob haller wrote:
> 120 volt in, 35 volts out 1.2 amps I am having a hard time finding a
> 35 or 36 volts out transformer.

2 transformers, 18V secondaries, 120V primaries.
Primaries in parallel, secondaries in series in phase.


# ----------+
---+-------)||( |
120VAC | )||( 18VAC |
| )||( |
-------+---)||( |
| | ----+ +-----
| | | 36VAC
| | # ----+ +-----
+-------)||( |
| )||( 18VAC |
| )||( |
+---)||( |
----------+

The transformers in the above example are MPJA #7843 TR
http://www.mpja.com/prodinfo.asp?number=7843+TR
They cost $5.63 each and are rated at 18V 2.0 amps secondary.

The # symbol is for phasing. The secondaries have center
taps - don't use them.

Ed
From: baron on 20 Jan 2010 05:05
ehsjr Inscribed thus:

> bob haller wrote:
>> 120 volt in, 35 volts out 1.2 amps I am having a hard time finding a
>> 35 or 36 volts out transformer.
>
> 2 transformers, 18V secondaries, 120V primaries.
> Primaries in parallel, secondaries in series in phase.
>
>
> # ----------+
> ---+-------)||( |
> 120VAC | )||( 18VAC |
> | )||( |
> -------+---)||( |
> | | ----+ +-----
> | | | 36VAC
> | | # ----+ +-----
> +-------)||( |
> | )||( 18VAC |
> | )||( |
> +---)||( |
> ----------+
>
> The transformers in the above example are MPJA #7843 TR
> http://www.mpja.com/prodinfo.asp?number=7843+TR
> They cost $5.63 each and are rated at 18V 2.0 amps secondary.
>
> The # symbol is for phasing. The secondaries have center
> taps - don't use them.
>
> Ed

Probably no help, but I recall that the old Deskjet 500 printer used a
transformer with a 38v AC output at about 2amps. I still use one !
When I get home I'll crawl under the bench and have a look.

--
Best Regards:
Baron.
From: Michael Black on 20 Jan 2010 11:17
On Tue, 19 Jan 2010, bob haller wrote:

> 120 volt in, 35 volts out 1.2 amps I am having a hard time finding a
> 35 or 36 volts out transformer.
>
Junked stereo amplifiers are likely to have higher output transformers.

What do you need it for? That factors in, since it defines how close
the voltage has to be, and such.

I once needed 24DC to run a Mac Powerbook, and while digging around to
find a suitable transformer, I remembered the inkjet printers I had lying
around. I opened one up, and immediately found a switching supply that
was easy to extract, and provided 24vdc of suitable amperage. That beat
finding a good enough transformer and then building a power supply. But
being able to do that depends on what the transformer is needed for.

Michael

From: news on 20 Jan 2010 12:19
On Tue, 19 Jan 2010 19:14:43 -0800 (PST), bob haller <hallerb(a)aol.com>
wrote:

>120 volt in, 35 volts out 1.2 amps I am having a hard time finding a
>35 or 36 volts out transformer.

How about this one?
http://skycraftsurplus.com/36vac.aspx

36volts CT at 2.8 amps

$8.00 plus shipping

John
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