Unknown Transformer----details required

[vinodquilon]

I am planning to tap a telephone line (to feed DTMF decoder as shown in the attachment) through an isolation transformer 600Ω/600Ω of 1:1 type. In our local market it is not readily avail. After a lot of search I have found one Dax 56K DX-56PU modem contains one Transformer .

Find the attachment T1 AASUPREME.
For using that Transformer I have to know the following details.
How can I know the following 4 specifications of the transformer,
Impedance matching (intended value is 600 ohms to 600 ohms)
Frequency response (intended value is 300-3400Hz for Plain Old Telephone System)
Turns ratio (intended value is 1:1)
Does it pass DC current through windings (otherwise I have to use separate capacitors at primary to block DC)

Complete Transformer specification-
aasupreme by
C US 0514
S022168A

I cannot get the specifications through internet.

 

[(*steve*)]

A lot of information seems to be available here.

Does it pass DC current through windings (otherwise I have to use separate capacitors at primary to block DC)

DC can pass through the individual windings of a transformer, but only an AC voltage on one winding will be coupled to the other winding.

 

[Resqueline]

1: Impedance is a function of frequency. The transformer is just a mediator between the two sides' impedances, and only needs its own inductance to be high enough to make sure the lowest frequency is transferred w/o attenuation. Being used in a modem it's likely to be a 600 ohm tx.
2: For sure it will cover that range, being used in a modem. Try it between an MP3 & a headset and listen to the sound quality.
3: Measure the resistance of the windings. If they are fairly equal it's a 1:1 tx.
4: ??? Of course a winding conduct DC. Of course separate windings are isolated does not transfer DC. Measure..