USER MANUAL EA915X Digital telephone hybrid Manufacturer: Eela audio Het Riet 8A 5431NM Cuijk The Netherlands Tel: (+31) 485 331182 Fax: (+31) 485 315505 E-mail: info@eela.info Internet: www.eela-audio.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Contents. Preface. Warning CE-Product Maintanance Waste Disposal! Purpose. Realisation. Installation. Dilswitch Settings. Dilswitch 1. Dilswitch 2 & 3. Making the correct setting. Dilswitch 4. Voltageless lines. Use 2 or 4 Wire mode in EELA AUDIO consoles ? Connections. Power. Receive. Send. Line. Phone. In/Out/Remote. Alignment hybrid. Send level. Receive level. Adjustment of the hybrid damping (echo-cancelling). Use. Answering and ending a call.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Flash. Update. Dilswitch. Hybrid crosstalk. Receive. Send. Limiter. A/D. Bypass. Auto answer. TB. Faults list. Connection is lost at activating the hybrid. R-bal en C-bal alignment not satisfactory. Echo canceller does not respond. Echo canceller does not give sufficient damping. Echo canceller setting does not stop after 2 seconds. Hybrid can not be switched off locally or remote. Unsufficient receive signal. Insufficient send signal. Blockdiagram.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Preface. Warning Do not expose the Digital hybrid to rain or high humid environments, to avoid danger of fire or electric shock. To reduce the risk of electrical shock, do not remove covers (or back) when unit is powered up. No user-servicable parts inside. Refer for servicing to qualified service personnel only. Modification or servicing by unqualified personnel will void the warranty.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Purpose. The main purpose of the EA915X is to be used as an interface to make a connection between a telephone line and a mixing console, with the highest possible quality and reliability. To obtain this purpose, the EA915X uses a Digital Signal Processor which reduces the crosstalk, normally existing in a hybrid circuitry, to a minimum. Realisation.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Dilswitch 2 & 3. With these dilswitches the behaviour of the automatic control for the minimum hybrid crosstalk is set. Dependant of the application the best automatic control method can be selected. DILSW2 OFF OFF DILSW3 OFF ON ON OFF ON ON CROSSTALK SETTINGS (CANCELLATION) After switching the hybrid on, the automatic adjustment is active for approx. 2 seconds. After that, the adjustment can be repeated by pressing the UPDATE switch..
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Voltageless lines. In some occasions (some in-house telephone exchanges) the telephone line does not carry any voltage for the extensions. Within the hybrid you can find 4 jumpers with which its telephone circuit can be adapted to this different application regarding these telephone lines. The factory setting for these jumpers is in the position for the hybrid to be used on normal telephone lines (carrying linevoltage).
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Receive. This is the signal coming from the caller so being the output of the hybrid. This signal should be fed into the input of an audio mixing console. Send. This is the signal to be sent to the caller and is the input signal for the hybrid. This signal comes from a (clean feed) output of the audio mixing console. Line. Connection for the telephone line. Phone.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE order not to damage the slot of the trimpots. Send level. The hybrid is set out in such a way that when putting the SND control in the centre position the nominal input level of the SEND input is set to +6dBm. The adjustment range of the SND control is + en -12 dB with reference to this nominal level. The send level has to be aligned as follows: Apply to the hybrid input by means of the controls of the mixing console a nominal signal.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Use. The EELA AUDIO hybrid of course can be easily interfaced with all EELA AUDIO "telephone" modules from the S130, S340 and S440 series consoles: An incoming call is also indicated on the channel and the hybrid can be activated (diverted) from the channel. In the S130 series, no Auto Answer and Ready indication is possible. In the S340 and S440 consoles, the software of this telephone channels also offers the possibility of Auto Answer.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Technical specifications. Technical specifications are valid under the following conditions: • All controls in center position. • 22Hz - 22kHz Bandwidth. • 600 Ohms source and terminating impedance for line adjustments. • Voltageless line input circuitry. • Line (tel) input -12dBm, send input +6dBm, both @1kHz. Send. Send input sensitivity : - 6dBm ... +18dBm. Send gain adjustment range : +/- 12dB. Limiter threshold : +6 dBm. Output noise : < -70 dBm.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Glossary. Fig.1 In fig1 the hybrid crosstalk is shown from a random connection. Note that every new test will give another result. The upper curve shows the crosstalk with the digital echo canceller switched off by means of the BYPASS switch; the lower curve shows the crosstalk with the digital circuitry active. DSP. Stands for Digital Signal Processor. This is a processor, specially meant to perform digital calculations on analogue signals. Hybrid.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Codec. Stands for short for a Coder / Decoder combination. Also often used as name for an A/D and D/A converter combined in 1 housing. Echo-canceller. System eliminating crosstalk in a hybrid circuit. Ring. Not audible call signal of the EA915X unit. Cancel. Term for eliminate or escape. Flash. Is a type of memory. This type of memory is re-writable and does not need a supply voltage to retain its data. Update.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Bypass. Is to activate the situation where the digital echo canceller is not used (bypassed). Auto answer. Process of automatically answering an incoming call over the telephone. TB. Is the abbreviation used for Talk Back. Faults list. Always make sure that the unit receives supply voltage. Connection is lost at activating the hybrid.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Unsufficient receive signal. If this only occurs occasionally, the cause can be found in the caller or the line. If this is a continuos phenomena, the RCV control might not been aligned correct. If the signal does not contain any low frequencies, chances are that the balanced signal is not interfaced properly to a subsequent (unbalanced) input circuitry. Insufficient send signal.
EA915X DIGITAL TELEPHONE HYBRID INSTRUCTIONS FOR USE Blockdiagram.
