DIY Tweed Deluxe 5e3 question

[gabasa]

If Modulus had a wiring diagram on their website, then this would be so easy. It never fun playing, “guess the wire” on a power transformer.

This kind of reminds me of when Ed Harris had to guess the wires near the end of The Abyss movie.

 

[Lowerleftcoast]

I don't understand that the black PT wire on the other side of the switch.

(black wire from circuit board upper left corner to bottom of standby switch) from what I can only guess is the power transformer's B+ (high tension/high voltage secondary) center tap (again, black wire in the Modulus diagram).

Modulus shows a diagram for the 120/240 version of the PT with Black as the HT CT.

 

[chas.wahl]

I guess I (and OP) didn't look hard enough on the Modulus site? Got a link?

 

[CirrusBand]

I built one of these using the modulus PT in November, the above wiring diagram matches what I've got. But... don't be afraid to contact Michael @ Modulus for confirmation - he gives great support.

 

[Lowerleftcoast]

Modulus site? Got a link?

Deluxe Power Transformer - MEGASTACK

DELUXE STYLE POWER TRANSFORMER - MEGASTACKThis is a over spec Deluxe style power transformer made to be a direct fit on our Tweed Deluxe chassis and

modulusamplification.com

 

[chas.wahl]

Ah, the confusion is that OP has the Deluxe PT that's not the Megastack, and that PT doesn't have a diagram. They're probably similar enough, but @Duelling Banjo should probably connect with Modulus to confirm. My suspicion is that the Megastack is only different in that it has more iron and higher current capability on B+ (the layout shows a connection of violet and gray wires, which is appropriate for 240 V mains); but if it's a dual-primary, 120 or 240 V item, then Modulus should be very clear (with a diagram like the Megastack's) about how that's supposed to be handled.

 

[King Fan]

Is there any remaining doubt regarding the PT wiring we're seeing in the pics?

 

[Lowerleftcoast]

Is there any remaining doubt regarding the PT wiring we're seeing in the pics?

If there is a doubt, it is easy enough to measure for low resistance from the reds to black. It is just a coil of wire with a tap at the mid point.

 

[King Fan]

Yeah, good point. I was assuming the black wire from PT to standby switch was the HT CT, but a resistance measurement is better than an assumption.

 

[Duelling Banjo]

Thank you all so much for your enthusiastic feedback, I'm quite overwhelmed by both the volume of feedback and indeed by the technical complexities and differing views on what I naively assume was a simple thing with a right/wrong answer. So my approach will be simply to finish the build as per the Modulus diagram, under the assumption it is 'correct' (or at least a working example) then see if it works and how it sounds. Regarding emailing Modulus I did that before posting my question but have not had a response. I'll post back once the build is complete, and if any problems, maybe ask for your help on how to fix them

 

[King Fan]

So my approach will be simply to finish the build as per the Modulus diagram, under the assumption it is 'correct' (or at least a working example) then see if it works and how it sounds.

Good for you; keep it simple. For early builds I always suggest a couple other ideas.

Reading, learning, planning, studying, sketching, thinking are free, fun, and very safe. Trouble-shooting something that doesn't work is the opposite in every way.

PT wiring is not the only item that may need a choice or a clearer understanding. Ask any other questions that come up here, share any thoughts or decisions you're not sure of, and take an hour or a day while the crowd-source answers come back. Heh, with this crew, you may even have some sorting to do.

Enjoy the journey. You can play the amp for the rest of your life, but you can only enjoy the build while it's happening.

 

[Duelling Banjo]

Thanks @King Fan

 

[mountainhick]

Thank you all so much for your enthusiastic feedback, I'm quite overwhelmed by both the volume of feedback and indeed by the technical complexities and differing views on what I naively assume was a simple thing with a right/wrong answer. So my approach will be simply to finish the build as per the Modulus diagram, under the assumption it is 'correct' (or at least a working example) then see if it works and how it sounds. Regarding emailing Modulus I did that before posting my question but have not had a response. I'll post back once the build is complete, and if any problems, maybe ask for your help on how to fix them

You have had the standard flood of information coming here! It was pretty overwhelming for me starting here, so much to learn... still.

For your project at hand, it will work fine as drawn, and your transformer wiring looks to be accurate to the drawing. If you want to keep it simple, continue with the build as is, and try it.

You also have the options to elevate the heater ground and do away with the standby switch. These are preferred options for many of us.

Form there is so much detail, some of these guys have a lifetime of knowledge...

Next build.

 

[Lowerleftcoast]

Good choice to wire it like the Modulus layout. They have a sensible well thought out version compared to the other companies.

Let us know how it turns out.