[Geoff C]

I'm looking for basic info on Fender vintage guitar amplifiers such as used
on 6V6 push-pull designs, such as "deluxe 5E3" "Super Champ".

Specifically I would like to know primary and secondary number of turns,
rated impedances, primary inductance and core size. Web links would be most
helpful.

[Geoff C]

"Bret Ludwig" wrote in
oups.com:


Geoff C wrote:
I'm looking for basic info on Fender vintage guitar amplifiers such
as used on 6V6 push-pull designs, such as "deluxe 5E3" "Super Champ".

Specifically I would like to know primary and secondary number of
turns, rated impedances, primary inductance and core size. Web links
would be most helpful.

Best bet is to buy one and test it. There are many who have done so
but they are not going to publish their work. Fender amps after CBS
use Schumacher transformers and Fender doesn't own any of the designs,
Schumacher does. Before that they used mostly Triad OEM types.

You can now buy Fender transformers at very reasonable prices, at
least wholesale, from several sources.



I should add I am in Australia and if I was gonna buy a Fender tranny I may
as well use that one in my homebrew amp rather than wind one...

[Ned Carlson]

Geoff C wrote:

I'm looking for basic info on Fender vintage guitar amplifiers such as used
on 6V6 push-pull designs, such as "deluxe 5E3" "Super Champ".

Specifically I would like to know primary and secondary number of turns,
rated impedances, primary inductance and core size. Web links would be most
helpful.

You can find some basic specs with a little googling:
http://www.unclespot.com/FenderXFMRs.html


The rest of the stuff.... these were not anything special,
things like primary inductance were probably measured on a
sample, not spec'd by the OEM. Turns ratio? Probably as few
as they could get away with. The important spec is that little
shim for the core gap. The old ones would be paper insulated, the
newer ones on a plastic bobbin.

You could probably do as well just by pulling a transformer
out of a junk console radio with EL84's. I really can't see
that even with the shipping costs to Oz, that you'd be better
off trying to build one than buying off the shelf.

--
Ned Carlson
SW side of Chicago, USA
www.tubezone.net

[Ned Carlson]

Bret Ludwig wrote:

Fender amps after CBS use
Schumacher transformers and Fender doesn't own any of the designs,
Schumacher does.

The designs are generic and a number of places
(at least 3 I can think of, offhand) other than
Schumacher make or have made Fender knockoffs.

--
Ned Carlson
SW side of Chicago, USA
www.tubezone.net

[Geoff C]

Ned Carlson wrote in
:

Geoff C wrote:

I'm looking for basic info on Fender vintage guitar amplifiers such
as used on 6V6 push-pull designs, such as "deluxe 5E3" "Super Champ".

Specifically I would like to know primary and secondary number of
turns, rated impedances, primary inductance and core size. Web links
would be most helpful.

You can find some basic specs with a little googling:
http://www.unclespot.com/FenderXFMRs.html


Thanks, saw that site but missed the bit on OP trannies



The rest of the stuff.... these were not anything special,
things like primary inductance were probably measured on a
sample, not spec'd by the OEM. Turns ratio? Probably as few
as they could get away with. The important spec is that little
shim for the core gap.

Does not matter for PP.

The old ones would be paper insulated, the
newer ones on a plastic bobbin.

You could probably do as well just by pulling a transformer
out of a junk console radio with EL84's. I really can't see
that even with the shipping costs to Oz, that you'd be better
off trying to build one than buying off the shelf.


True, but I already have access to laminations, bobbins, wire, turns
counter, mylar tape, etc.

[Geoff C]

"Bret Ludwig" wrote in news:1162525641.273230.70860
@m7g2000cwm.googlegroups.com:


Geoff C wrote:


You can find some basic specs with a little googling:
http://www.unclespot.com/FenderXFMRs.html


Thanks, saw that site but missed the bit on OP trannies



The rest of the stuff.... these were not anything special,
things like primary inductance were probably measured on a
sample, not spec'd by the OEM. Turns ratio? Probably as few
as they could get away with. The important spec is that little
shim for the core gap.

Does not matter for PP.

Actually it does. EI lam transformers always have "some" effective
gap, and well designed ones have a definite and repeatable one. The
tradeoff is the more gap, the lower the primary inductance, and bass
response goes to hell,

Yes, there is always a small airgap with EI, I know that but this is a
guitar amp and so long as the PI and ouputs are balances well enough, the
DC is not much problem. The first tranny I tried saturated badly at more
than 5 watts in push pull, so i know I need more iron. I will trade off
the primary inductance with air gap should there be any sign of LF
saturation, but that will be done on an empirical basis.

You could probably do as well just by pulling a transformer
out of a junk console radio with EL84's. I really can't see
that even with the shipping costs to Oz, that you'd be better
off trying to build one than buying off the shelf.


True, but I already have access to laminations, bobbins, wire, turns
counter, mylar tape, etc.

You might as well start with some arbitrary assumptions and work one
up yourself to taste.



Yep, already worked out I need about 2300 primary turns on my 1 1/2"
core, which should do a 50 watt design if I decide later on too.

[Phil Allison]

"Geoff C"


Yes, there is always a small airgap with EI, I know that but this is a
guitar amp and so long as the PI and ouputs are balances well enough, the
DC is not much problem. The first tranny I tried saturated badly at more
than 5 watts in push pull, so i know I need more iron.


** What ********.

Power output is not determined by core saturation.

Core saturation only sets a low frequency power limit.



......... Phil

[Geoff C]

"Bret Ludwig" wrote in
oups.com:

This is a very incomplete list but looks about right.

Note the high 8500 ohm primary Z of the Deluxe and princeton types.
Most of the old Fisher and Scott pulls we used as replacements were
lower and that made the poor little tubes work harder...they didn't
seem to have any shorter lives though. The loundess was higher and no
one bitched (au contraire..)



FENDER TRANSFORMER WIRE DIAGRAMS AND SPECIFICATIONS

FENDER OUTPUT TRANSFORMER WIRING


FENDER OUTPUT TRANSFORMER SPECS
PART# MOUNTING HEIGHT LENGTH WIDTH WATTS
PRIMARY SEC LBS 022921 1 ¾" 1 ¾" 1 3/8"
1 3/8" 3.5 14,500 4 6 OZ 022905 2 3/8" 1
5/8" 1 7/8" 1 7/8" 8 7000 4 12 OZ 022913
2 13/16" 2" 2 5/16" 2" 12 8500 8
1 LB 041318 3 1/8" 2 ¼" 2 ¾" 2 ¼" 25
8500 8 1.5 LB 022848 3 9/16" 2 5/8" 3 1/8"
2 5/8" 50 4000 4 2 LB 018343 2 3/16 X 3
7/16 3 7/16 4 1/8" 3 5/8" 50 4000 2,4,8
6 LB 022871 2 3/16 X 3 7/16 3 7/16 4 1/8" 3
5/8" 40 4000 4 6 LB 022855 2 3/16 X 3 7/16
3 7/16 4 1/8" 3 5/8" 50 4000 2 6 LB
022899 2 3/16 X 3 7/16 3 7/16 4 1/8" 3 7/8"
100 2000 4 7 LB

FENDER CHOKES
PART# MOUNTING HEIGHT LENGTH WIDTH LBS
125C3A 2" 1 3/8" 1 11/16" 1 ½" 6 OZ
125C1A 2 13/16" 2" 2 5/16" 2" 1 LB









FENDER POWER TRANSFORMER WIRING

FENDER POWER TRANSFORMER SPECS
PART# MOUNTING HEIGHT LENGTH WIDTH WATTS
MAIN SEC HEATER HEATER
LBS
TDPT-SU 2 1/4 x
2 1/2 2 7/8 3 3/8 3 25 614Vac 6.3V
5V 4.2 LB
TDPT-LD - - - - 25 614Vac 6.3V
5V 4.2 LB
125P1B 2 ½ X 2" 3 ¼" 3" 2 ½" 6 - 18 650V
/ 70MA 6.3V / 2A 5V / 2A 4 LB
041316 2 7/8 X
2 ¼" 3 7/8" 3 3/8" 2 7/16" 25 660V / 120MA
6.3V / 3A 5V / 3A 5 LB
022798 3 3/8 X
2 ¾" 3 3/8" 4 1/8" 3 3/8" 50 700V / 140MA
6.3V / 4A 5V / 3A 6 LB
022756 3 ¾ X 3" 3 7/8 4 ½" 3 ¾" 100 690V
/ 310MA 6.3V / 6A
NONE 8 LB


Thanks for the info. I've seen most of this now. I would love to know how
many turns/volt the old designs used though, and for that i would need to
know number of turns, or even an inductance value.

[Ned Carlson]

Geoff C wrote:

Does not matter for PP.


D'oh! I saw "Champ" and just assumed it was single-ended.


True, but I already have access to laminations, bobbins, wire, turns
counter, mylar tape, etc.

Lucky you. I would note that if you want to make something
like a 1950's transformer, plastic bobbins and mylar tape
are out. That doesn't mean you can't make a nice transformer
with a plastic bobbin and insulation, though.


--
Ned Carlson
SW side of Chicago, USA
www.tubezone.net

[Phil Allison]

"François Yves Le Gal"
"Phil Allison" :

Power output is not determined by core saturation.
Core saturation only sets a low frequency power limit.


If a transformer can deliver 100 w at 200 Hz and only 10 w at 20 Hz
because
of core saturation, power output is determined by core saturation.


** What asinine, Frog logic ********.





........ Phil

[Geoff C]

"Bret Ludwig" wrote in
oups.com:

Note: The author of this message requested that it not be archived.
This
message will be removed from Groups in 6 days (Nov 10, 8:26 am).

On Thu, 02 Nov 2006 05:37:39 GMT, Geoff C
wrote:
Does not matter for PP.

It does if you do have some DC surimposed when it comes to mains
transformers or unbalanced (ie.. shifted relative to 0) DC voltage for
output xformers.

Transformers don't like DC - toroids don't like it at all; they can
saturate
quite easily, leading to poor power coupling as well as dirty sound -
which
can be OK for a guitar amp which is after all an instrument.

Reply » Rate this post:


Except that the distortion sound of a DC-saturated toroid nay not be
at all what a guitar player wants. remember, they weant a very
specific type of distortion, not just any old kind.

Slit or otherwise less-saturable toroid cores are available but they
are expensive and a much larger core must be used as well.



I found the sound of a saturating core really bad. It was happening at the
low frequency end with my unknown 16k:8k transformer. Should have a better
tranny to try soon

[ralf]

On 5 Nov 2006 15:26:42 +1100, Geoff C wrote:

"Bret Ludwig" wrote in
roups.com:

Note: The author of this message requested that it not be archived.
This
message will be removed from Groups in 6 days (Nov 10, 8:26 am).

On Thu, 02 Nov 2006 05:37:39 GMT, Geoff C
wrote:
Does not matter for PP.

It does if you do have some DC surimposed when it comes to mains
transformers or unbalanced (ie.. shifted relative to 0) DC voltage for
output xformers.

Transformers don't like DC - toroids don't like it at all; they can
saturate
quite easily, leading to poor power coupling as well as dirty sound -
which
can be OK for a guitar amp which is after all an instrument.

Reply » Rate this post:


Except that the distortion sound of a DC-saturated toroid nay not be
at all what a guitar player wants. remember, they weant a very
specific type of distortion, not just any old kind.

Slit or otherwise less-saturable toroid cores are available but they
are expensive and a much larger core must be used as well.



I found the sound of a saturating core really bad. It was happening at the
low frequency end with my unknown 16k:8k transformer. Should have a better
tranny to try soon

I had trouble with this site just now but this guy used to have some
xformer info on the old time Fender stuff:
www.hoffmanamps.com
If you are experimenting you could try the Hammond 125 series
(Canadian) which is intended as an inexpensive, universal type which
means you can swaps the leads about and get different ratios, loads
and tube matches. These are cheap, reliable and sound great in small
guitar amps for about $30usd. I didn't notice any earthshaking
difference in sound other than the bass sound of the instrument kind
of shifted up or down slightly as you tried different taps. The tubes
never overheated or glowed or burst or seemed to act any differently.
My understanding and approach isn't exactly scientific though.
Good luck.

[Geoff C]

ralf wrote in
:

On 5 Nov 2006 15:26:42 +1100, Geoff C wrote:

"Bret Ludwig" wrote in
groups.com:

Note: The author of this message requested that it not be archived.
This
message will be removed from Groups in 6 days (Nov 10, 8:26 am).

On Thu, 02 Nov 2006 05:37:39 GMT, Geoff C
wrote:
Does not matter for PP.

It does if you do have some DC surimposed when it comes to mains
transformers or unbalanced (ie.. shifted relative to 0) DC voltage
for output xformers.

Transformers don't like DC - toroids don't like it at all; they can
saturate
quite easily, leading to poor power coupling as well as dirty sound
- which
can be OK for a guitar amp which is after all an instrument.

Reply » Rate this post:


Except that the distortion sound of a DC-saturated toroid nay not
be
at all what a guitar player wants. remember, they weant a very
specific type of distortion, not just any old kind.

Slit or otherwise less-saturable toroid cores are available but
they
are expensive and a much larger core must be used as well.



I found the sound of a saturating core really bad. It was happening at
the low frequency end with my unknown 16k:8k transformer. Should have
a better tranny to try soon

I had trouble with this site just now but this guy used to have some
xformer info on the old time Fender stuff:
www.hoffmanamps.com
If you are experimenting you could try the Hammond 125 series
(Canadian) which is intended as an inexpensive, universal type which
means you can swaps the leads about and get different ratios, loads
and tube matches. These are cheap, reliable and sound great in small
guitar amps for about $30usd. I didn't notice any earthshaking
difference in sound other than the bass sound of the instrument kind
of shifted up or down slightly as you tried different taps. The tubes
never overheated or glowed or burst or seemed to act any differently.
My understanding and approach isn't exactly scientific though.
Good luck.



Thnaks. Some interesting stuff but not quite everything. Anyway, I'm not
trying to make a Fender clone, just get a starting point to check my
design against before the winding starts. I'm aiming for a 36H primary
inductance and 8K:4,8 ohms. Thats about 2300 turns on my core.