Wiring UTC A-10 and A-24...looking for tips....

[stitch-o]

Hey people,
The topic I will through out there is more likely simple enough for most but new for me.
To my defense, I've invested hours at this point researching and have hit a wall.
As always, I completely appreciate all comments and critisms...

on to the question:
I'm building a [Silent:arts] d-la2a and I would really like to use original UTC A-10 on input and A-24 on output. The design calls for Sowter 4383 on in and 8940 on out.
I've attached the primary and secondary diagrams I've sketched so far for both the Sowter and UTCs.
I want to wire 600-50k and 15k-600 respectively.

On the UTC's, this is what I think I might/should be doing to get above mentioned values:
-strap 8&9 and use 7&10 for hi/lo?
-1&6 are hi/lo input (a-10) and output (a-24), then strap 3&4 and leave 2&5 bare and unconnected
-ground on UTC will be black on both sowters.

any ideas?

Cheers and thanks!

 

[Sredna]

According to the LA2A-scematic:

A-10

Pin 1 = 600Ohm (-) input
Pin 2 = 250Ohm (+) input
Pin 3 and 4 connected (input centre tap)
Pin 5 = 250Ohm (-) input
Pin 6 = 600Ohm (+) input
Pin 7 is connected to 68kOhm resistor (R5) and (R6) (R6 is strapped between Pin 7 & 10)
Pin 8 and 9 connected
Pin 10 connected to circuit ground and transformer core

A-24

Pin 1 = 600Ohm (+) output (goes to meter)
Pin 2 = unconnected
Pin 3 and 4 connected (output centre tap)
Pin 5 = unconnected
Pin 6 = 600Ohm (-) output (goes to meter)
Pin 7 is connected to C3
Pin 8 and 9 connected
Pin 10 connected to circuit ground and transformer core

Hope this helps.

Regards,

Anders

 

[stitch-o]

yes, this a great place to start:::cheers!
I am studying this as well:::http://www.waltzingbear.com/Schematics/Urei/LA_2.htm

after reading schemo and looking at my drawings, It looks as if I am not so far off the mark maybe...
Interesting: I would need to strap pin 10 and ground on the A-24 together and then ground to chassis (?), I think. Interesting...

So, I've come up with the scheme in format to answer my own question I think:

A-10/4383
pin     lead color
1        Green
3/4     Pink
6        Brown
7        Blue
10      Grey
GND   Black

A-24/8940
pin     lead color
1       Grey
6       Pink
7       Yellow
10     Green
GND  Black


2 and 5 are unconnected on both

any other observations welcome.

 

[salomonander]

can anyone confirm the above pinouts?

 

[salomonander]

bump