V374a questions... and some haufer trafo info.

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

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

synthi

Well-known member
Joined
Jun 9, 2004
Messages
560
Location
Madrid (SPAIN)
Hi People,

I have some of these line amp I`m trying to connect.
The data and schematic are here:

http://www.kubarth.de/diy/german/index.html

Look for V374, it covers a, b and c versions. Sorry I can add a direct link for the files.

Well, I can`t understand German :sad: , but I think I got some points:

-0v,24V and Chassis are obvious
-For balanced input I must bridge 5 and 6
-Gain in set by a resistor between 9 and 10, do you think a 25K log pot will work there?

Now the part I`m missing:

I can`t understand how to connect the balanced input and outputs, I`d like to get 1 input and 2 outputs but I see several points for eingang and ausgang, including those "mitte" points that I can`t understand...
Please could anyone take alook at this and help me to connect the in and out?

Thanks!

Synthi.

PS: Here are the promised haufer data :razz: , those trafos are used in an old siemens mixer I got:

http://personal.telefonica.terra.es/web/audio24bit/haufe/ST4404.jpg
http://personal.telefonica.terra.es/web/audio24bit/haufe/ST4404-A.jpg
http://personal.telefonica.terra.es/web/audio24bit/haufe/ST4579.jpg
 
the main difference between the (TAB) a b and c versions is the level of the second output: 0dB @ a, 3 or 9 dB @ b, 15 dB @ c.

for the a and b version:
1 = Input +
2 = Input -
3/4 bridged for balanced Input
5 and 6 = unbalanced Input
9 and 10 = gain
10 = unbalanced Out
19 = Out 1+
20 = Out 1-
22 = output transformer 1 centertap
23 = output transformer 2 secondary 1 +
24 = output transformer 2 secondary 2 -
25 = output transformer 2 secondary 2 +
26 = output transformer 2 secondary 1 -
7, 8, 21, 29 = 0V
30 = chassis
31 = +24V

[edit] pin numbers on output transformer 2 have been wrong
 
Thanks silentarts!

But there seems there are some errors, the data sheet say bridge 5-6 for symm input, right?
the three "23" pins i thing are 23, 24 and 25(?)
then, for adding the second output I must bridge 25&26 and get + from 23 and - from 24?
Out 1 is 15Kohm, what if i get out 2 from 23-26 or 24-25? also what the centertaps are used for?

Thanks again,

Synthi.
 
[quote author="synthi"]the data sheet say bridge 5-6 for symm input, right?[/quote]
right. otherwise you don't have the + of the transformers secondary connected to the circuit.

the three "23" pins i thing are 23, 24 and 25(?)
sorry about that, copy & paste error :oops: (corrected this)

then, for adding the second output I must bridge 25&26 and get + from 23 and - from 24?
yes

Out 1 is 15Kohm, what if i get out 2 from 23-26 or 24-25? also what the centertaps are used for?
if you mean "Eingangsscheinwiederstand" - it's the input impedance, not the output. for waht the centertap was used for I don't know.
 
Back
Top