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About to put in a 125ESE_Do I have this right?


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About to put in a Hammond 125ESE tonight, I think I've read enough and should have no problems if what I've got is right.

 

Is this right? :

-White wire of 125ESE to 16 ohm

-Yellow wire of 125ESE to 8 ohm

-Green wire of 125ESE to 4 ohm

-Brown wire of 125ESE to T3 (female spade connector)

-Blue wire of 125ESE to T4 (female spade connector)

-Orange wire of 125ESE Insulated (not connected to anything)

-Black wire of 125ESE to Ground on the jack PC board

 

If this is right the only thing I not 100% sure of is the Black wire.

Do I just solder it to the ground (2nd from end) on the jack's board?

Do I leave the Green/Yellow wire that's already there going to ground the way it is?

 

If anything above is wrong then I guess I need somebody to explain it all to me like I'm a 3 year old.

 

Any other advice? Like wire twist or placement to keep noice interferrance problems away?

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Eh. I'll explain how the damn thing works :-s

 

An output transformer is a pair of disconnected wire coils using electromagnetic inductance to generate a current flow. Basically, the primary coil has the power from the power amp flowed through it; the secondary coil outputs to the speaker/hot plate/etc. The two coils have different impedance; really the 4/8/16 ohm outputs are broken at different points of the single secondary (output) coil.

 

To transfer power from one coil to another, an alternating current crosses the primary coil. When the current switches direction, the magnetic field generated by the coil collapses and reforms. The amplitude of the signal influences the power of the field, and the amplitude of the output signal. When a magnetic field collapses across a coil (i.e. across the secondary coil) it causes a current flow, so the secondary coil sends power to the speakers (bang).

 

That being said, we'll discuss how the circuit actually works. The output is 16, 8, and 4 for white, yellow, and green when the primary is 5000 ohms (wow). The black wire is the common; so each output connects to black (i.e. power is White and ground is Black to connect a 16 ohm jack; notice there's 2 wires hooked up to the output jacks?). This means, yes, please only use one output jack at a time; and they all plug into the black wire. Ignore the orange wire; insulate it.

 

Brown and Blue are your primary coil connectors. They get the input signal, and connect across T3 and T4. Which is which I don't think matters because we're dealing with AC. (I'm not sure on this. Really AC usually means T1 is more negative than T2, then T2 is more negative than T1; but we're talking about a diode here, the tube will only let current flow one way. Still, the amplitude is going up and down; it's +600 versus something like +400 - +600, which will still drive a magnetic field to form and collapse as described.) Swapping them will change the direction of current flow, but not the amplitude; still, it might drive the speaker the opposite way (instead of in out in out it might go out in out in?), I don't know.

 

The thing to understand about a coil is that as the power level changes, the magnetic field changes; this change causes resistance in the wire. If you just throw DC across it, it's a wire, no resistance (for the same reason, trying to use +5V +12V as a signal reference limits the amount of data you can shove over a hard drive interface; the wires basically act like low-capacity capacitors, and a longer wire does it more effectively hence bigger coil more impedance). Thus we call this "impedance" and yes it changes based on frequency.

 

Basically the device is just about that simple. I didn't quite get wiring it up at first; once I figured out how it worked it just made sense. There's no magic signal carrying circuitry inside, it's all a matter of short circuiting.

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About to put in a Hammond 125ESE tonight' date=' I think I've read enough and should have no problems if what I've got is right.

 

Is this right? :

-White wire of 125ESE to 16 ohm

-Yellow wire of 125ESE to 8 ohm

-Green wire of 125ESE to 4 ohm

-Brown wire of 125ESE to T3 (female spade connector)

-Blue wire of 125ESE to T4 (female spade connector)

-Orange wire of 125ESE Insulated (not connected to anything)

-Black wire of 125ESE to Ground on the jack PC board

 

If this is right the only thing I not 100% sure of is the Black wire.

Do I just solder it to the ground (2nd from end) on the jack's board?

Do I leave the Green/Yellow wire that's already there going to ground the way it is?

 

If anything above is wrong then I guess I need somebody to explain it all to me like I'm a 3 year old.

[/quote']

 

Yep. The stock green/yellow wire connects all the jack and OT grounds (the black one) to chassis ground. Gotta have it. Everything else you've described sounds like you're ready to go for it. So go for it!

 

Any other advice? Like wire twist or placement to keep noice interferrance problems away?

 

 

Yep. Keep the speaker tap wires short. Twist the the blue and brown primary wires, and keep them away from everything! Use chopsticks to find the best place for them to be so they won't cause oscillation (squealing pig gremlins). Then figure out a way to secure them to that spot so they won't move.

 

Gil...

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Thanks alot Blue & Gil. Very helpful.

Haven't got it done tonight.I'm not haveing any trouble, just a slower process than I though (that glue is annoying). Also kinda side tracked with taking pics of everything as it is stock first. Thought it'd be a good idea to have for reference. Gettin to bed now, so I'll post update tomorrow sometime. Hopefully about how good it sounds.:-k/

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Just to update: The ESE Really lets the sound out of this babe.

I already pretty much liked it stock for clean home lower volumes.Now I love it.

Put a bright switch in at R2 while I was at it.I Like that too.Gives it a little more clear input signal I think. As far clean lower volumes with a coil taping guitar I'm getting just about any thing I want out of this thing. Now I want to get another VJ just to store away so I never find myself with out one.

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