HOW TO strapd 60 OR 70 IN THE CARD TMU TO SEE 600 OHM

[sayoudbilel]

HI
In MD110 VERSION: CXP1010117/2/BC12SP6/R3B


HOW TO strapd 60 OR 70 IN THE CARD TMU TO SEE 600 OHM


WATCH THE IMAGER ATTACH AND SAY ME IS TRUE OR FOULST

 

[inlsp05]

155 12-ROF 137 5335/1 Uen A1



TMU

Contents
1 General

2
Straps for selection of the input impedance
2.1 600 ohm impedance
2.2 10 kohm impedance

3
Straps for the relative level

4
PCB current limiting device

5
Board status on delivery



1 General

TMU is a printed board assembly for tone sending, tone receiving, conference and connection of sound equipment for the feature Music On Hold.

Music On Hold is used for sending music to persons that are waiting for answer. TMU has two analogue inputs for this purpose.

With straps the input impedance can be changed from 600 ohm to high-ohmic. With other straps the level of the analogue inputs can be selected.

Each input has a relay to control the external sound equipment.

The board contains six current limiting devices that are implemented in the layout foil. If such a device blows it shall be replaced by a fuse that is soldered.

2 Straps for selection of the input impedance

The two analogue inputs of TMU can be strapped for 600 ohm or highohmic impedance (10 kohm). At delivery the inputs are strapped for 600 ohm impedance.

At delivery the strap is implemented as a foil at the printed circuit board ( see Figure 2-1 , item 60 and 70).

To obtain 10 kohm input impedance the foil strap shall be removed (cut).

To restore 600 ohm impedance a wire strap shall be inserted between the two solder pads.

2.1 600 ohm impedance

When a sound equipment with 600 ohm output impedance is connected to a TMU-input the input shall be strapped for 600 ohm. (Strap shall be inserted)

Strap 60 inserted enables 600 ohm impedance at input one.
Strap 70 inserted enables 600 ohm impedance at input two.
( see Figure 2-1 )


2.2 10 kohm impedance

2.2.1 2-7 inputs

When a sound equipment with 600 ohm output impedance is connected to more than one (maximum 7) input(s) only one input shall be strapped for 600 ohm.
The remaining inputs shall be strapped for 10 kohm.

Strap 60 removed enables 10 kohm impedance at input one.
Strap 70 removed enables 10 kohm impedance at input two.

Example

A sound equipment with 600 ohm output impedance connected to 7 inputs.

Input 1 strapped for 600 ohm impedance
Inputs 2-7 strapped for 10 kohm impedance


graphics3

Figure 2-1.


2.2.2 More than seven inputs

If the sound equipment is connected to more than seven inputs all straps shall be removed.

3 Straps for the relative level

The level of the two analogue inputs is adjustable between -6 dBr to +6 dBr in step of three decibel. The strap is a foil strap as above.

At delivery the inputs are strapped for zero dBr.

Inserted straps depending on desired input level:

Input 1 Input 2
+6 dBr strap 61 strap 71
+3 dBr strap 62 strap 72
0 dBr strap 63 strap 73
-3 dBr strap 64 strap 74
-6 dBr strap 65 strap 75

see Figure 2-1

4 PCB current limiting device

The board is equipped with current limiting devices in the layout foil.
The current limiters are intended to protect the printed board assembly from high current.
The board is strapped with a replacement fuse if the PCB current limiting device is blown.
NGH 323 01/500 (Littelfuse 251.500 L) shall be used as replacement fuse. The new fuse is mounted over the current limiting foils on the component side of the board.

If one of the PCB current limiting devices 400 to 403 is destroyed the PCB current limiting device on the other branch shall be cut as well. Add new fuses on both branches. This is done in order to minimize unbalance to earth.

Current limiting device 400 and 401 are connected to inlet one.
Current limiting device 402 and 403 are connected to inlet two.
Current limiting device 404 is connected to the relay for inlet one.
Current limiting device 405 is connected to the relay for inlet two.

see Figure 2-1


5 Board status on delivery

The input impedance is strapped for 600 ohm.

The input level is strapped for 0 dBr.

The board is delivered with PCB current limiting devices in the layout foil.


graphics4

Figure 5-1.

SEE attachment and stop shuting with CAPSLOCK

PG4E

 

[himdp]

Hi inlsp05,
this question was asked by the same user in March last year and answered already. Is it possible that he as a different version of TMU as shown in the graphic attached to his earlier thread this month asking the same question?

Question asked last year.

https://www.tek-tips.com/viewthread.cfm?qid=1785261

Question asked earlier this month

https://www.tek-tips.com/viewthread.cfm?qid=1796871

 

[inlsp05]

Hi Himdp you right ! some people no search in forum and just start new topic ....

PG4E