Neumann M49 Clone : Build Thread Puck Style (TLM49 Conversion To M49 b-c)

[kmozart]

Yes, poctop's M49b with Peluso capsule (later killed in an accident) and AMI T49 tranny, sounded absolutely gorgeous.

Which Peluso capsule was it, CEK-47 or P-K47, I just noticed there are two different ones...

 

[poctop]

Yes, poctop's M49b with Peluso capsule (later killed in an accident) and AMI T49 tranny, sounded absolutely gorgeous.

Which Peluso capsule was it, CEK-47 or P-K47, I just noticed there are two different ones...

it was the P-47,
Best,
Dan,

 

[kmozart]

On the input of my triad VP-T230-110 I'm applying 120 (that what my main is) and on the out I'm getting 136AC. Is that normal?
Im tying up on the in Blue and Violet then Gray and Brown, and on the out red-yellow and black-orange. That should be good right?

When I hook that up to the AC in of the board, with no load, just testing the power supply, I'm getting this:

B+ the lowest I can adjust with the R8  trimmer is 129.4DC
H+ the lowest I can go with the pot is 20.15DC
Polarization I can get 129.1DC for 8
                                                  64.5DC for Cardioid
                                                          0DC for omni


Is there a problem? if it is, Where should I look into?

Thanks!

 

[kmozart]

Another Newbie question; Do you cut the pins/leads 8 and 4 off the tube?  (5840)?

Not Clear on the pictures,...

 

[poctop]

On the input of my triad VP-T230-110 I'm applying 120 (that what my main is) and on the out I'm getting 136AC. Is that normal?
Im tying up on the in Blue and Violet then Gray and Brown, and on the out red-yellow and black-orange. That should be good right?

When I hook that up to the AC in of the board, with no load, just testing the power supply, I'm getting this:

B+ the lowest I can adjust with the R8  trimmer is 129.4DC
H+ the lowest I can go with the pot is 20.15DC
Polarization I can get 129.1DC for 8
                                                  64.5DC for Cardioid
                                                          0DC for omni


Is there a problem? if it is, Where should I look into?

Thanks!

if you have no load this is normal to see higher voltage  , this is a passive PSU,
so when the mic is connected it will load down to proper value for adjustement ,

 

[poctop]

Another Newbie question; Do you cut the pins/leads 8 and 4 off the tube?  (5840)?

Not Clear on the pictures,...

yes you can cut them as they are redundant ,
Best,
Dan,

 

[kmozart]

Thanks Poctop!!!

 

[kmozart]

Just Double check:

5840 tube:

Pin 1 to FGRID
Pin 2 to K
Pin 3 to H+
Pin 4 - Cut
Pin 5 and Pin 7 Tied together to A
Pin 6 toHG
Pin 8 - Cut

Right?

THANKS!

 

[poctop]

Yes this is Correct

Best,
Dan,

 

[kmozart]

Hello Everybody,

Do you know any good source for the round bodies? Just like the original ones?  Like Poctop's prototype? Where I can use it with Yokemount and Binder series 691 - 7 pin connector?

Thanks!

 

[poctop]

Hello Everybody,

Do you know any good source for the round bodies? Just like the original ones?  Like Poctop's prototype? Where I can use it with Yokemount and Binder series 691 - 7 pin connector?

Thanks!

Contact AMI and ask for Dennis,

or Here  http://groupdiy.com/index.php?topic=52563.0
Best,
Dan,

 

[kmozart]

Ok I got all together but the body and capsule. Still debating myself about what capsule to use.

This is the problem I have. I think my voltages are off, when I connect all together, this is what I got:

Any Idea What got wrong?
Thanks!

 

[poctop]

Ok I got all together but the body and capsule. Still debating myself about what capsule to use.

This is the problem I have. I think my voltages are off, when I connect all together, this is what I got:

Any Idea What got wrong?
Thanks!

Very Very Nice Build , Congrats so far,  8)
could you let me know wich picture represent wich voltage , I can guess quite easilly but it would be so much better for this thread  8)
did you adjust each of the voltage with the corresponding Potentiometer, ex.. B+ H+, Bias Pot
as far as i can tell you are pretty smack on the value , for B+ backplate and bias what about the heater at 6.3V

What tube is it , what is the 1.68V on the psu reading ?  is this the heater voltage ?

Let me know,
Dan,

 

[kmozart]

Thanks Dan!

Voltages on the Mic:

K= 1.612V - Pic 1
A = 122.4v -  Pic 2
H+ = 1.623 - Pic 3 
Pin 5 = 123.8v - Pic 4
#4 power supply = 1.683v - Pic 5
#6 Power Supply - 059.7 - Pic 6
#5 Power Supply - 123.7v  - Pic 7


I can control A Voltage on the mic with R8, but that is the lowest it goes. 
I can control K on the mic and #4 on Power Supply with the Pot.

This is the tube I use:

Power Supply ( Used the box before for something else,>..)

 

[poctop]

Thanks Dan!

Voltages on the Mic:

K= 1.612V - Pic 1
A = 122.4v -  Pic 2
H+ = 1.623 - Pic 3 
Pin 5 = 123.8v - Pic 4
#4 power supply = 1.683v - Pic 5
#6 Power Supply - 059.7 - Pic 6
#5 Power Supply - 123.7v  - Pic 7


I can control A Voltage on the mic with R8, but that is the lowest it goes. 
I can control K on the mic and #4 on Power Supply with the Pot.

This is the tube I use:

Power Supply ( Used the box before for something else,>..)

ok disconnect the mic immediately,
the problem is the heater voltage you have no emission hence no plate current that is why the Anode voltage is so high,
i think you have issue with the wiring of the 20 VAC traffo ,
how did you configure it ,
show me how it is wired or draw a little somthing ,

only this part is suspect.
Best ,
Dan,

 

[poctop]

Have A Look at this ,

Connect pin 5 and 8 to PSU PCB. ( Valid For North America )
Best,
Dan,

 

[kmozart]

OK, This is how I have it wired:

When Is not connected to the board I'm Getting 25.61V on 5 and 6

 

[kmozart]

Have A Look at this ,

Connect pin 5 and 8 to PSU PCB. ( Valid For North America )
Best,
Dan,

Yep That is what I have!  Sorry i wrote 6 in the picture! 

 

[kmozart]

ok disconnect the mic immediately,
the problem is the heater voltage you have no emission hence no plate current that is why the Anode voltage is so high,
i think you have issue with the wiring of the 20 VAC traffo ,
how did you configure it ,
show me how it is wired or draw a little somthing ,

only this part is suspect.
Best ,
Dan,

Any other idea?

Thanks Dan for helping!

 

[poctop]

ok disconnect the mic immediately,
the problem is the heater voltage you have no emission hence no plate current that is why the Anode voltage is so high,
i think you have issue with the wiring of the 20 VAC traffo ,
how did you configure it ,
show me how it is wired or draw a little somthing ,

only this part is suspect.
Best ,
Dan,

Any other idea?

Thanks Dan for helping!

what is the voltage up the heater when you disconnect the mic ,
D