Re: Neumann M49 Clone : Build Thread Puck Style (TLM49 Conversion To M49 b-c)
« Reply #340 on: December 20, 2017, 12:14:15 AM »
"Input1: Series – BLUE and BROWN, Jumper GRAY to VIOLET
Parallel – BLUE and BROWN, Jumper BLUE to VIOLET, GRAY to BROWN

Output1: Series – BLACK and YELLOW, Jumper RED to ORANGE
Parallel – BLACK and YELLOW, Jumper BLACK to ORANGE, RED to YELLOW"

So on the AC input, Blue and Violet together, and Gray and Brown together. 

On the output, Black and Orange together, and Red and Yellow together.

My question is, if I maintain the proper parallel wiring as in wire Blue and Violet to neutral, and Gray and Brown to Hot on my IEC, does this dictate which pair of secondaries goes to either spot on the PSU board?  Or is phase reversal at the PSU not possible?  I don't see reference to such a distinction on the PSU schematic pg1 one of this thread. 

Another way of saying it - does Blue and Violet on the primary side = Black and Orange on the secondary side?  Or does it = Red/Yellow, or neither?  I feel like there is a piece of basic information I don't understand here.  Since the voltage is only transferred via magnetism, does this direct relationship not exist?


Re: Neumann M49 Clone : Build Thread Puck Style (TLM49 Conversion To M49 b-c)
« Reply #341 on: December 20, 2017, 12:25:47 AM »
The data sheet makes sense.  This reads like paralleled windings on the primary.  As for the secondary, the voltage is rectified so the polarity of the AC on the rectifier input makes no difference as long as the rectifier itself is installed properly.  Some of those rectifier bridge assemblies have the AC inputs, and the + and - DC outputs marked or embossed on the case.

Re: Neumann M49 Clone : Build Thread Puck Style (TLM49 Conversion To M49 b-c)
« Reply #342 on: December 21, 2017, 12:27:17 AM »
Thank you for clearing that up.  I can understand this transformer now.

I see on the PCB where I am to connect AC20v as well as AC120v, and they both go to a series of diodes on the PCB.

So the next thing is looking at the 20v transformer, I assume this is stepping down from 115v to 20v.  Shown here as 187b20 http://www.mouser.com/ds/2/177/186-187-948805.pdf

Looking at the lugs here https://www.hammfg.com/files/products/186-187/186-187bulletin.pdf in figure 7b, I see lugs 2/3 are the primary with lug 2 being the coil start of the primary.

On the secondary side, I see 5-7(7 is a center tap) is one coil, and 5-8 is both coils, with 5 being coil start.  I am not clear on which two lugs to wire on the secondary to get 20v here.  I've read both sheets and I can't seem to find a description like the toroid has.  I assume this is because I don't have the basic knowledge of reading a transformer schematic correctly.  Could you give me a hint on how I know which lugs to use on the secondary of the Hammond?

There is also the small issue of this Triad filter reactor as well.  I apologize for being uneducated here.  I am looking at the PSU schematic from page one and I don't see what is what here.

TillM

Re: Neumann M49 Clone : Build Thread Puck Style (TLM49 Conversion To M49 b-c)
« Reply #343 on: December 31, 2017, 07:59:16 AM »
After one week my M49 work flawless it stopped passed audio today :(
I was really shocked and went to trouble check.
I noticed, that H+ is still on 6,2v and K is 1,6V.
But now it comes.
B+ is hanging on 0,9v to 1,1v instead of 120v.
I biased my B+ trimmer to 119,8v.
What is happened ?
The Tube still burns and no capacitor in the PSU seams to be broken. No smoke and so one.
What could happened ?
Where I've to start my trouble check ?
Hope you guys can help me.

EDIT: Found the mistake. I burned my fuse. I just had to find out, why my fuse burned down
« Last Edit: December 31, 2017, 08:15:57 AM by TillM »

Re: Neumann M49 Clone : Build Thread Puck Style (TLM49 Conversion To M49 b-c)
« Reply #344 on: January 01, 2018, 02:49:02 AM »
Need to figure out why the fuse blew... Unless there is a short or other problem, the fuse should not fail...