Geofex splitter questions

[Kinetic]

I'm looking at building the Geofex splitter circuit (schematic: http://www.geofex.com/FX_images/splitter.gif) for sending my guitar signal to 2 amps at once.

I've never built anything with a transformer before, got a couple of questions.
1) Will any 1:1 audio transformer do, or does it need to be that Mouser one?  Banzai have this one: http://www.banzaimusic.com/TM018-Transformer.html
2) How do you wire the transformer? Each coil has 3 leads, it seems, how does that relate to the circuit diagram?

Plus some more general questions:
3) The text says "do not connect ISO1 and 2 jacks to metal box"  - does this imply that I should use a non-metal enclosure, or am I missing the point?
4) What op-amp would be best to use?
5) I the upper (power) part of the diagram, there are three transistors but only 2 clear labels.  I presume that both of the lower transistors are 2N3904s?

Thanks a lot.

[Bad Chizzle]

The transformers are being used to isolate the two grounds I believe. If you grounded the jacks you would be defeating the purpose of the final section. Any transformer with the same specs would work. I believe if you want one to one, you use the outside leads. Test with meter to get the correct ratio. Find very quiet opamps for this build. Research them,I real don't know which is best for this build.
2n3904 are probly good all around.

Hope I helped ya some! I think I'm correct on these points.

Chuk

[PRR]

> Will any 1:1 audio transformer do

No.

> does it need to be that Mouser one?

No.

> Banzai have this one

Same part. "018" is the basic part number, in a line of transformers developed in the late 1950s for miniature (especially transistor) systems. Mouser's "TM" may be who made their version, or what kind of wax is used, but I am sure the Banzai is equivalent for your uses.

Ignore the center pin on each side. One side is primary, the other is secondary, and they are interchangable (goes either way).

Use TL071 or TL072.

[Kinetic]

Great, thank you both for your help.

My only remaining question is about the ISO jacks and the metal box.  I presume that this is a ground issue, so if I mount those two jacks on a plastic sheet and fix it to the enclosure, would that solve the problem?

[Bad Chizzle]

Yes, that sounds like a very good idea! Good thinking

[Processaurus]

Great, thank you both for your help.

My only remaining question is about the ISO jacks and the metal box.  I presume that this is a ground issue, so if I mount those two jacks on a plastic sheet and fix it to the enclosure, would that solve the problem?

It is easy for the metal threads on the jacks to touch the side of the hole in the metal box.  People either use a special collared insulated washer to float the jack in the exact middle of the hole and ensure it does not ever touch the sides, or easier, just use a plastic jack.