How can I remove the center tap connection from an Edcor output transformer?

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

midwayfair

Well-known member
Joined
Apr 7, 2015
Messages
606
Location
Baltimore
I'd like to convert the 1:4s I have to 1:2s, because I can't really think of anything to do with them otherwise. I'd swear I saw something about doing it, but I can't remember where and my search-fu isn't up to snuff tonight.
 
CJ said:
which model?  need diagram.

Duh. Sorry! These:

http://www.edcorusa.com/xsm_series

0002072_xsm-series.png


I thought I would be able to just use the center tap instead of one of the outside pins, but it didn't sound like I expected -- it was very dark sounding and weird.
 
midwayfair said:
CJ said:
which model?  need diagram.

Duh. Sorry! These:

http://www.edcorusa.com/xsm_series

0002072_xsm-series.png


I thought I would be able to just use the center tap instead of one of the outside pins, but it didn't sound like I expected -- it was very dark sounding and weird.

You should be able to use it as 1:2 using pins 1-4 and pins 5-6 in standard transformers
Potentially you could try 1-4 and 6-8.
Am not sure if removing center tap change anything,
Measure resistances at the secondry this could give some light on the internal connection.
 
I think I must have done something wrong the last time I tried this, then. I'll hook it up on the breadboard tonight and do some measurements with a test signal.

Thanks for the help as always, folks.

Actually, I just figured out why I was confused: It's a center tap, not a pair of coils that could be wired in parallel. I was thinking it would be a situation where the - of a "top" coil and + of a "bottom" coil were already connected to form a center tap, but that's not what's going on here, right?
 
> a situation where the - of a "top" coil and + of a "bottom" coil were already connected to form a center tap,

It is; but you can't "break the CT" and make it two coils four leads.

Use half the winding, end to CT. It should work 90+% as good as an optimum design. Using half the available copper is not a big deal.
 
PRR said:
It should work 90+% as good as an optimum design.

I feel like I'm obliged to ask "what's the drawback" :)

Maybe lower power handling -- meaning that I only get the headroom of a 1:4 with the voltage output of a 1:2?
 
You can break the CT; just desolder it.  Both leads are right there on the terminal. 
 
Higher DCR. If the winding space were two coils you could put in parallel, it might be say 100r DCR.If you can only use one of the windings (because the connection point is inaccessible), it will be 200r. On a say 10K or even 2K winding, that's no big deal.

"Power Handling" is essentially unchanged.
 
Back
Top