SE Electronics Z3300a

[micolas]

for my tube mic project I thought using this type of connector (for HT) they exist in 2 to 9 pins
but I'll open later a new thread on this topic...
[/QUOTE

Better.
A group administrator will probably give us a warning

 

[micolas]

Yeah ! the U47 Fet in the box calls me "come & get me"

Many things are calling us!
We all suffer from GAS
Gear Acquisition Syndrome

 

[Emmathom]

Hi Khron ! what do you think about all that stuff ?

 

[micolas]

@Khron @Emmathom

SC 1100

... and now let's see why it doesn't work.

 

[Khron]

Hi Khron ! what do you think about all that stuff ?

No idea, i "tuned out" several pages ago...

 

[Emmathom]

Hi @micolas
I got the Monacor transformers from my friend and measured them.
At primary, in static, I find: 73Ω and 64Ω therefore in series = 137Ω
At secondary, still in static: 91Ω (lowest value)
So it's a 1,5:1 ratio
Does that seem correct to you?

PS: the LTR-110 transformer that I have in my possession offers 4 inputs to the primary (so 2 separate coils and not 3 as in the documentation) and 4 outputs to the secondary: 1 is not connected to anything, the others give according to 183Ω or 91Ω wiring...

 

[micolas]

Hi @micolas
I got the Monacor transformers from my friend and measured them.
At primary, in static, I find: 73Ω and 64Ω therefore in series = 137Ω
At secondary, still in static: 91Ω (lowest value)
So it's a 1,5:1 ratio
Does that seem correct to you?

PS: the LTR-110 transformer that I have in my possession offers 4 inputs to the primary (so 2 separate coils and not 3 as in the documentation) and 4 outputs to the secondary: 1 is not connected to anything, the others give according to 183Ω or 91Ω wiring...

Not.
It's about the voltage ratio.

Please be more explicit, make a clear diagram with windings and ohmic resistance (in DC)

Is the ohmic resistance for the windings for the LTR-110 transformer?
If yes then it's ok.
You should make the connections as I drew you yesterday.
However, you need to measure the transformer ratio.


*Method 1:
Take a low-power 1..3W mains transformer, which is fed at U1= 230v/50 Hz AC (European standard) and outputs U2=3...6v AC in the secondary.
Connect U2 to the primary of the audio transformer. At the secondary audio transf connect a resistor of 3.9...4.7 Kohm to have a load. Connect to mains 230v/50Hz, U1
Now measure the alternating voltage (50Hz) across the primary of the audio transformer : Uaudio1 (a few volts). It also measures the alternating voltage at the secondary output of the audio transformer Uaudio2.
Transformer ratio will be accurate enough
Ratio= Uaudio1 : Uaudio2
* Method 2:
With a signal generator, you inject a voltage of several volts of 1kHz into the primary of the audio transformer.
If you have an oscilloscope, measure the voltage Uaudio1 and Uaudio2 and make the raport
Ratio=Uaudio1 : Uaudio2
You can repeat the measurements at several frequencies, 100Hz, 200Hz, 500Hz, 2kHz, 5kHz, 10Khz, 15Khz, etc., knowing that at low frequencies the audio transformer has lower efficiency, losses, etc., depending on the core size.
If you don't have an oscilloscope, in principle it would work with a better DMM.

 

[Emmathom]

I don't have an oscilloscope...
what is DMM?

thank you for your reply but why make these measurements with an alternating voltage etc...knowing that I have no other solution than to use these transformers LTR-110 for the present.
all I wanted to know is if these values (137Ω input / 91Ω output) seem correct to you ?
I will install the 137Ω side in the primary and therefore the 91Ω side in the secondary and test the microphone...
if it sounds good, let's go foward

 

[micolas]

I don't have an oscilloscope...
what is DMM?

Digital Multi Meter

 

[micolas]

Are these the coils on the transformer you have now?

 

[Emmathom]

4 pins in (and not 3) / 4 pins out (and not 5)
different from documentation (and Audiophonics website)

 

[micolas]

4 pins in (and not 3) / 4 pins out (and not 5)
different from documentation (and Audiophonics website)

Did you also receive a diagram with the connections?
There are 8 terminals, it seems ok

 

[Emmathom]

official doc. inside the box...

 

[Emmathom]

Please... micolas, answer my first question : do these 137Ω & 91Ω I measured seem ok to you ???
... even if it means more 1,5:1 than 2:1
Then we'll see how to deal with it

 

[micolas]

Please... micolas, answer my first question : do these 137Ω & 91Ω I measured seem ok to you ???
... even if it means more 1,5:1 than 2:1
Then we'll see how to deal with it

It's ok.
We do a first test:
We consider the primary between
1 and 3 and the secondary between
6 and 7.
Solder it in the microphone.
That's about 4:1

 

[Emmathom]

No... as I measured, you must wire it like that :
1 (2+3 in serie) 4 > input
6 7 > ouput

 

[micolas]

No... as I measured, you must wire it like that :
1 (2+3 in serie) 4 > input
6 7 > ouput

NOT.
Connect as I said.

 

[Emmathom]

There's no Ω between 1 and 3 but ok I will do so...
What about 8 ? "in the air" or connected to ground (pin 1) ? and the not connected pin (up right) ?

 

[micolas]

There's no Ω between 1 and 3 but ok I will do so...
What about 8 ? "in the air" or connected to ground (pin 1) ? and the not connected pin (up right) ?

look carefully at the marking of the terminals, they are not in order
Vue de dessous!

 

[Emmathom]

look carefully at the marking of the terminals, they are not in order

you want me to respect strictly the marking ? even if I don't measure any impedance btw these connections ?
Ok I will follow you (it's not instinctive... !) but this will be tomorrow morning 'cause now I must care about my family.
Will let you know tomorrow. Thank you +++ micolas