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

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kmozart said:
H+ with no mic is 20.89v

then Something is Pulling too much current ,
I suggest then you install a load resistor between pin 4 and ground to rule out the psu ,
somthing like 47 ohm 1 W , you can stick it between pin 4 and gnd right in the xlr connector on the psu ,
this will load it at about 150ma for 6.3V , then you will be able to rule out the mic or psu ,

Best,
Dan, 
 
poctop said:
kmozart said:
H+ with no mic is 20.89v

then Something is Pulling too much current ,
I suggest then you install a load resistor between pin 4 and ground to rule out the psu ,
somthing like 47 ohm 1 W , you can stick it between pin 4 and gnd right in the xlr connector on the psu ,
this will load it at about 150ma for 6.3V , then you will be able to rule out the mic or psu ,

Best,
Dan,

Thanks Dan. With No mic, How much voltage should I have at H+?

Is there something else wrong?  Pot Wired wrong?
 
kmozart said:
poctop said:
kmozart said:
H+ with no mic is 20.89v

then Something is Pulling too much current ,
I suggest then you install a load resistor between pin 4 and ground to rule out the psu ,
somthing like 47 ohm 1 W , you can stick it between pin 4 and gnd right in the xlr connector on the psu ,
this will load it at about 150ma for 6.3V , then you will be able to rule out the mic or psu ,

Best,
Dan,

Thanks Dan. With No mic, How much voltage should I have at H+?

Is there something else wrong?  Pot Wired wrong?

you should be able to adjust the pot for 6.3V at 150ma with no mic connected and the dummy  load installed, 
if not then PSU got somthing wrong ,
Best,
Dan,
 
poctop said:
[q
you should be able to adjust the pot for 6.3V at 150ma with no mic connected and the dummy  load installed, 
if not then PSU got somthing wrong ,
Best,
Dan,

These are the voltages following the schematic:

- After the diodes at C13 - 29.36V
- after R2  - 28.99v
- X1-2 - 28.86v
- X1-1 - 28.57v
- after R6 - 27.93v
-after R11  -  27.27v
- the lowest I can go with the POT is 19.78v

Could not find any leaky cap in the path, all the negative side of them has no voltage
 
kmozart said:
poctop said:
[q
you should be able to adjust the pot for 6.3V at 150ma with no mic connected and the dummy  load installed, 
if not then PSU got somthing wrong ,
Best,
Dan,

and this is with the dummy load resistor installed ?,
dan,


These are the voltages following the schematic:

- After the diodes at C13 - 29.36V
- after R2  - 28.99v
- X1-2 - 28.86v
- X1-1 - 28.57v
- after R6 - 27.93v
-after R11  -  27.27v
- the lowest I can go with the POT is 19.78v

Could not find any leaky cap in the path, all the negative side of them has no voltage
 
OK!!!  With the 47Ohm 1W connected from 4 on the board to the body of the XLR I can Adjust just fine to 6.3V!! So it is the Microphone...  What should I check first?


Thanks
 
I had wired the board 1 to 7 with the connector 1-7 corresponding.
Then the cable is wired 1 thru 7 on the corresponding one on the other side. Applied the load on the female side of the cable pins 4 and 7, with the male connected to the Powersupply, and I was able to adjust to 6.3V.

I have wired the male binder to the microphone board 1 thru 7 with reversing pins 3 and 7.  connector pin 3 is wired to the board 7 and connector 7 is wired with the board 3.  Also I do not have any capsule on the board if that matters.

Is that ok?

 
kmozart said:
I had wired the board 1 to 7 with the connector 1-7 corresponding.
Then the cable is wired 1 thru 7 on the corresponding one on the other side. Applied the load on the female side of the cable pins 4 and 7, with the male connected to the Powersupply, and I was able to adjust to 6.3V.

I have wired the male binder to the microphone board 1 thru 7 with reversing pins 3 and 7.  connector pin 3 is wired to the board 7 and connector 7 is wired with the board 3.  Also I do not have any capsule on the board if that matters.

Is that ok?

The capsule doesnt matter ,  if you have reversed pin 3 and 7 note that on the psu pin 3 is a sheild lift not a ground so the circuit ground should go on pin 7 , but on the mic boar it says 3 this one is reversed ,  hence make sure you have installed the jumper labeled SHLF on the psu board ,  i have made a excel spreadsheet in this thread to mention this ,
a couple of pages back ,  Let me know if you have installed the jumper SHLF specially if you have inverted it ,
Best,
DAn,
 
poctop said:
kmozart said:
I had wired the board 1 to 7 with the connector 1-7 corresponding.
Then the cable is wired 1 thru 7 on the corresponding one on the other side. Applied the load on the female side of the cable pins 4 and 7, with the male connected to the Powersupply, and I was able to adjust to 6.3V.

I have wired the male binder to the microphone board 1 thru 7 with reversing pins 3 and 7.  connector pin 3 is wired to the board 7 and connector 7 is wired with the board 3.  Also I do not have any capsule on the board if that matters.

Is that ok?

The capsule doesnt matter ,  if you have reversed pin 3 and 7 note that on the psu pin 3 is a sheild lift not a ground so the circuit ground should go on pin 7 , but on the mic boar it says 3 this one is reversed ,  hence make sure you have installed the jumper labeled SHLF on the psu board ,  i have made a excel spreadsheet in this thread to mention this ,
a couple of pages back ,  Let me know if you have installed the jumper SHLF specially if you have inverted it ,
Best,
DAn,

I have the jumper, yes.

After re-checking the mic cable (Gotham GAC-7 Tube) and the Binder connectors, and make sure everything is tight, I put the things back together, and all of the sudden I got right voltages;


PowerSupply:

H+ is 6.04v
B= is 116.0v



Mic:

K is 6.08v  ?!?! ( You have it at 1.6v couple of pages back in your picture)
A is 51.8v
H= is 6.03v
on 5 on the board I got 115.8v

Beside the K voltage, I guess I'm good? 

Thanks! 

I CAN SEE My Tube GLOW  !!!
 
kmozart said:
poctop said:
kmozart said:
I had wired the board 1 to 7 with the connector 1-7 corresponding.
Then the cable is wired 1 thru 7 on the corresponding one on the other side. Applied the load on the female side of the cable pins 4 and 7, with the male connected to the Powersupply, and I was able to adjust to 6.3V.

I have wired the male binder to the microphone board 1 thru 7 with reversing pins 3 and 7.  connector pin 3 is wired to the board 7 and connector 7 is wired with the board 3.  Also I do not have any capsule on the board if that matters.

Is that ok?

The capsule doesnt matter ,  if you have reversed pin 3 and 7 note that on the psu pin 3 is a sheild lift not a ground so the circuit ground should go on pin 7 , but on the mic boar it says 3 this one is reversed ,  hence make sure you have installed the jumper labeled SHLF on the psu board ,  i have made a excel spreadsheet in this thread to mention this ,
a couple of pages back ,  Let me know if you have installed the jumper SHLF specially if you have inverted it ,
Best,
DAn,

I have the jumper, yes.

After re-checking the mic cable (Gotham GAC-7 Tube) and the Binder connectors, and make sure everything is tight, I put the things back together, and all of the sudden I got right voltages;


PowerSupply:

H+ is 6.04v
B= is 116.0v



Mic:

K is 6.08v  ?!?! ( You have it at 1.6v couple of pages back in your picture)
A is 51.8v
H= is 6.03v
on 5 on the board I got 115.8v

Beside the K voltage, I guess I'm good? 

Thanks! 

I CAN SEE My Tube GLOW  !!!

I CAN SEE My Tube GLOW  !!!

Yep Always a nice Feeling on this myself
If you can see your tube glow now , you are in business with the heater voltage at 6.03V,
regarding the bias , i am guessing you arew building the M49b correct ?
try measuring between grid and Kathode then as per schematic ,
but the most important is your plate voltage that you got right
IMHO,  put a capsule and Enjoy,.
Best,
DAn,

 
poctop said:
2_2.jpg


It is M49b. Measuring exactly like this:
 
Seems like the H= and K are having the same voltage now.

When I measure between HG and the K or HG and H= it is 6.20V
If I measure between Fgrid and H= and Fgrid and K it is 0.93v
 
kmozart said:
Seems like the H= and K are having the same voltage now.

When I measure between HG and the K or HG and H= it is 6.20V
If I measure between Fgrid and H= and Fgrid and K it is 0.93v

all Normal if you are tackling the M49b , if you look a the schematic  you will understand why,.
Best,
Dan,
 
I got an e-mail that Rigglers bodies are shipping,
I have to decide on a mic transformer using the 5840 tube.
I'd like to save some money and use the T-49, but if the BV's are better, I'll pop for those.
Any real use  comments on the BV11A, vs. BV11R vs. the T-49.

 
Just checking to make sure.
When using the remote pattern switching from the power supply, these two points are connected?
Is there a diagram for wiring the 7 pin XLR on the mic to the  mic's round P.S.B.s?
 

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Winetree said:
Just checking to make sure.
When using the remote pattern switching from the power supply, these two points are connected?

yes they are connected this is a cardiod only switch when off.

Is there a diagram for wiring the 7 pin XLR on the mic to the  mic's round P.S.B.s?

check here for cabling hints,
https://cdn.groupbuilder.com/groupdiy/u/39511/58d02819943e5.xlsx
best,
Dan,
 
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