Feedback We welcome feedback on any aspect of the Telos Hx1 or Hx2, or this manual. In the past, many good ideas from users have made their way into software revisions or new products. Please contact us with your comments.
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Telos Systems USA Telos Systems 1241 Superior Avenue E Cleveland, OH 44114 USA +1-216-241-7225 (phone) +1-216-241-4103 (fax) +1-216-622-0247 (24/7 Technical Support) Support@Telos-Systems.com Inquiry@Telos-Systems.com Notices and Cautions This symbol, wherever it appears, alerts you to the presence of uninsulated, dangerous voltage inside the enclosure –...
“What if?” was the query asked by Steve Church that led to the start of Telos Systems. In 1984, Steve – Pioneering ideas aren’t limited just to technology, then a young broadcast engineer and part-time talk though. We believe that investing in people pays off show host – wondered whether emerging Digital big, so we’ve assembled the largest R&D team in the...
| Introduction Hx1 Hybrid The Telos Hx1 is a single digital hybrid in a 1RU 19 inch rack mount enclosure. It embodies a state of the art approach to interfacing an analog POTS (Plain Old Telephone Service) line for broadcast on-air use. The fast, precise digital automatic- nulling hybrid allows smooth, natural, conversation without speakerphone-like up-cutting effects, or the audio distortion and feedback problems often experienced with lesser hybrid interface devices. The Hx1 implements a number of features in the digital domain in order to enhance “real-world” performance. In particular, the hybrid includes a sophisticated automatic gain control in both the send and receive paths, a carefully implemented override ducking system, a pitch shifter for feedback reduction, and a digital dynamic EQ that keeps audio spectrally consistent from call to call. Purpose Th e Telos Hx1 or Hx2 broadcast telephone hybrids are designed to deliver pure caller audio with as little leakage from the (announcer’s) send audio as possible. Telos uses state of the art digital techniques to perform the hybrid function – the subtraction of the send audio from the received caller audio. The fully digital approach assures consistently good trans-hybrid loss, audio levels and sound quality with varying telephone line conditions.
| Section 1 Features The Telos Hx1 and Hx2 hybrids include many features that have historically been “add ons” or options. See the list below. A high-pass filter reduces hum and low frequency noise. High- frequency ♦ noise above the telephone frequency range is also attenuated. A smart digital Automatic Gain Control (AGC) smooths output levels. The ♦ gain changes occur naturally, delivering consistent levels without processing artifacts. A settable noise gate/expander on the receive path reduces phone line noise during caller pauses. An adjustable override function allows ducking of the caller while the an- ♦ nouncer is speaking. Feedback is reduced by a special “pitch shifting” arrangement while echo is ♦ reduced with a basic Acoustic Echo Canceler. Fixed or adaptive EQ helps to correct deficiencies in a callers telephone set or ♦ the network, resulting in a clearer, warmer, more intelligible sound from the caller. Front panel metering is provided for input and output levels. EQ gain changes ♦ are displayed in real time. Auto-Answer capabilities with a selectable ring count allows for unattended ♦ operation. Worldwide disconnect signal detection allows use of the hybrid in different ♦ countries and with various PBXs. The Hx is equipped with a complete diagnostic system for system set-up and ♦ check-out. Optional AES3 support is available. ♦ Built-in universal power supply and rack mount design aids in a professional ♦ installation.
IntroductIon | Hx2 Hybrid The Telos Hx2 unit consists of two identical digital hybrids in a single 1RU 19 inch rack-mount enclosure. The Hx2 can operate as two fully independent hybrids or be configured with an internal mix-minus to couple the two hybrids, sharing a single mix minus from the audio console and allowing callers on both hybrids to hear each other and your talent. The Hx may be controlled remotely via connections available on the unit’s remote connector (DB-9). Control functions include remote on and off control, and available status outputs include “line ringing” and “hybrid in use” open-collector indications. The remote connector allows easy direct connection to 1A2 interfaces, consoles or other remote control devices. The unit can be equipped with an optional AES3 module, which plugs into the motherboard and converts the XLR connections from analog to AES3.
| Installation The Hx1 and 2 mount in a 1RU space in a standard 19” rack. The unit generates very little heat and needs no special attention for cooling or rack placement. The unit will operate in any envi- ronment where the stirred air temperature around the unit is between 0 to 40 degrees Celsius (32 to 104 degrees Fahrenheit) with a relative humidity of 0 to 98% (non-condensing). Next installation steps are: Connect your telco circuits and connect a “looped through” telephone set, if desired. ♦ Connect Audio with analog connections (or AES3 if equipped). ♦ Connect any needed parallel GPIO for remote control operation or to use any of the ♦ available status indications present on the rear panel DB-9 connector. Power up the Hx and do a quick basic operational test using the factory settings. ♦ This installation section covers all of the above. After completing these steps you’ll be ready to move on to configuration for your specific situation. 2.1 Connecting your telco lines The Hx1 & 2 use standard RJ-11 type “modular” telephone connectors. Only the two center pins that carry the analog line’s “tip and ring” are used. Connect the telephone line using the rear panel “LINE” jack. The Hx is designed to work with ordinary “loop start” analog phone lines, though it can oper- ate on PBX extensions and VoIP Analog Terminal Adapters (ATA’s). Hybrid performance and system behavior on these kinds of lines may vary. If you plan to use your Hx on any of these types of lines or connect your unit to other legacy Telos systems such as the 1A2 interface or the Direct Interface Module and others, please see section 2.7. Lines that carry “Shared Line DSL” can be problematic. It’s suggested that you avoid using the Hx on lines that carry DSL, but if you must use one, be sure to use a “line splitter” or DSL filter in series with the “LINE” jack on the Hx. DSL lines have data carriers above the voice band of the circuit, usually from 25 khz to 1004 khz. DSL filters strip away the high frequency data car- riers and pass on the 0-4 khz voice band and signaling. Some filters are better than others and sometimes better results can be obtained by cascading several filters, each rolling off more of the high frequency energy. On a line with DSL you might hear more “hiss” and “hash” than with a...
| Section 2 2.2 Studio Audio Connections Mix-Minus The Hx must be fed send-to-caller audio that is free of the caller audio, a ‘mix-minus’. A mix- minus is a mix of all of your audio sources that will be placed on-air (or recorded) except the caller audio – thus the mix-minus designation. The European term M-1 (mix minus one) is per- haps a clearer term. A mix-minus is also sometimes referred to as a ‘clean feed’. The important thing to remember is that the hybrid must not ‘chase its tail’ – the condition when its output makes its way somehow back to the input. Hot Tip Many hybrid installation problems are caused by an inadvertent signal path which creates a loop from the hybrid’s output back to its own input. Some consoles allow this when certain control combinations are selected by the user.
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InStallatIon | PGM Bus PGM Out Line Inputs Utility Bus To Rec Ch.1 Hybrid To Telco To Rec Ch.2 This arrangement is flexible, allowing the operator to place any or all sources in Utility for the caller to hear. In our example we have the fortunate case that the console permits the Utility bus to be fed pre-fader, letting the announcer easily use the telephone system for off-air conversa- tions. A recorder can be attached to the Utility and hybrid outputs to record announcer + phone audio. This is often done as shown here, with each signal to a separate track. A drawback is the potential for the operator to accidentally put the hybrid in Utility, in which case it is no longer a mix-minus. To avoid this error, the signal path could be permanently disconnected by removing the summing resistors, or some such creative operation. If no bus is available to feed the Hx, you could use an external mixer that bridges the micro- phone inputs to achieve the same effect. The Hx2 has multiple hybrids and works best if two faders can be assigned to the telephone system with two associated mix-minuses, one for each telephone line. This is probably not going to be easy with an older console. But the Hx2 has an option to work with a single external mix- minus by making an internal cross-connection of the hybrids. See Section 2.3 for more on this. Using a small mixer A small audio mixer is used to record interviews off the telephone line using a single hybrid. The mixer’s main bus is fed to the recording device. Both the microphone and the hybrid will be brought up on the faders so the interview can be recorded.
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| Section 2 Using a production-style console The Production-style consoles often used for TV audio will have multiple Aux send busses that can be used in a similar way to the small mixer example above. Each hybrid is sent from an Aux bus and everything the caller needs to hear is mixed into that bus, taking care to keep the hybrid itself off the bus. Phones and Remotes When on remote, to save money and hassle, calls are usually received at the studio, rather than at the remote site. In this situation, caller audio must be fed to the remote talent so that they can hear and respond to callers. Moreover, the callers need to hear the talent. In many cases, the remotes are sufficiently distant that talent cannot monitor the station for the caller feed. Even if they could, the profanity delay would be a problem, since the talent needs to hear the callers pre-delay. All perceptual codecs (such as the Telos Zephyr or X-Stream) or any IP codec, have too much delay for talent at remote locations to hear themselves via a round-trip loop. Therefore, another mix-minus is required to feed a codec. The talent hears callers via the codec return path. As before, you feed this return with mix- minus: a mix of everything on the program bus minus the remote audio. As for the second half of the equation, the callers hear the talent because the remote feed is added to the telephone mix-minus bus. This is no problem if you have a set-up that permits selective assignment to the hybrid mix-minus.
Note The Telos Hx has the more common pin-outs used for three pin XLR inputs & outputs. You can easily remember the correct signals when wiring connectors using the phrase “George Washington Bridge.” Pin 1 = G = Ground, Pin 2 = W = “+” = White (typical color in mic cable, if there is no white there will be a red conductor), and Pin 3 = B = “-”...
10 | Section 2 The figure above illustrates which signals are combined together inside the Digital Signal Processor and routed to each connector when the Hx2 internal mix-minus feature is enabled. Use this option if you only have a single mix-minus available from your console and you wish to use both hybrids to conference callers on the air. You’ll still need a fader for each hybrid output. Bit #6 in the ‘OPTIONS’ DIP switch bank controls the mix-minus feature. The internal mix- minus feature is enabled when the switch is ON. The default factory setting is OFF - Disabled. 2.4 Input Audio Connection The input connection, SEND IN, has the following characteristics: XLR Pin 1 = Ground, ♦ XLR Pin 2 = High (Active Balanced, RF suppressed) ♦ XLR Pin 3 = Low (Active Balanced, RF suppressed) ♦ Bridging impedance, > 100K Ohm ♦...
Next to the input level pot is a pushbutton switch that selects between line and mic levels. When the pushbutton switch is in the LINE position (out), the input range of the SEND IN signal is –10 to +8 dBu. When the switch is in the MIC position (in), the input range of the SEND IN signal is –70 to –16 dBu. The inputs are designed to be sourced from balanced lines. Usually shielded cables have the shield wire connected only on one end (most often the input) to prevent ground loops. Older equipment with a transformer output stage may need a terminating resistor across pins 2 and 3 to maintain a proper “flat” frequency response; consult the manual for your equipment for how to use it with high impedance inputs. If you are connecting a device with an unbalanced output to your Hx, connect the shield from the output of your device to pin 1 (ground) on the Hx input, and the “hot” lead from your unbalanced output to pin 2 (high) on the Hx. Depending on the device, you might also want to try connecting pin 3 of the Hx input to ground, or even “floating” the ground and using only the high and low pins on the Hx. It’s also important that unbalanced lines be kept short to avoid hum and noise pickup. You’ll probably need to adjust the input gain on the Hx to match the output of your device. We also suggest that all of your audio equipment be powered from the same AC power source or circuit to prevent ground loops due to the use of multiple grounds. For complete information and suggested wiring and grounding techniques for your studio or recording workstation, please visit the support page at the Telos website: http://www.telos systems.com/support. 2.5 Output Audio Connection The output connection, RCV OUT, has the following characteristics: XLR Pin 1 = Ground, ♦ XLR Pin 2 = High (Active Balanced, RF suppressed) ♦ XLR Pin 3 = Low (Active Balanced, RF suppressed) ♦ Output impedance, < 60 Ohms ♦ Analog clip point at +24 dBu ♦ Digital-to-Analog converter resolution of 24 bits ♦...
12 | Section 2 The nominal output level is fixed at +4 dBu, with +20 dBu headroom to account for the crest factor of some audio signals. If you are connecting the output of your Hx to a device with an unbalanced input, connect the shield from your device’s unbalanced input to pin 1 (ground) on the Hx, and the “hot” lead from your device to pin 2. It’s important that unbalanced lines be kept short to avoid hum and noise pickup. We also suggest that all of your audio equipment be powered from the same AC power source or circuit to prevent ground loops due to the use of multiple grounds. For complete infor- mation on suggested wiring and grounding techniques for your studio or recording workstation, please visit the support page at the Telos website: http://www.telos-systems.com/support. 2.6 Remote Control The female DB9 connector on the Back Panel provides access to control functions. Pin 1 of the DB9 connector is Ground. Pins 2 through 5 on the top row are for GPIO input signals from the remote device, while Pins 6 through 9 on the bottom row are GPIO output signals to the remote device. Two of the GPIO input pins and two of the GPIO output pins are reserved for each hybrid as follows: Pin No. Function 1 GPIO Ground 2 GPIO IN Hybrid #1 - Hybrid ON 3 GPIO IN Hybrid #1 - Hybrid OFF...
InStallatIon | 13 ing it from the output to the +5v source on pin 8. An appropriate value is 2.2K Ohms. Sink (pull-down) current must be limited to 400mA maximum per output with total ♦ output restricted to 1 amp (200mA each output if all five will be used). The GPIO output pins can be used to provide status information to other devices or warning lamps. Outputs are available to indicate “hybrid in use” and “line ringing”. 2.7 Connecting Your Hx to other systems and non-standard lines We know that you’re creative and that we couldn’t hope to address every possible situation that you face, and armed with a little knowledge about how the Hx works internally, you should be successful with most applications of the Hx. In short: The Hx will operate on anything that electrically “looks like a POTS telephone line”. You can connect the Hx to anything that is designed to run a standard Analog telephone set. It needs loop current of 12-24 volts at 15-25 ma to run its line interface chip. The chip provides telephone line audio and line signaling status (on hook/off hook/ringing/loop drop, etc) to the processor to control the unit. If loop current isn’t present, you’ll have no audio and the Hx will simply hang up. This is correct behavior. Connect to PBX’s and VoIP Analog Terminal Adapters (ATA’s) When connecting to VoIP ATA’s or PBX station ports, and even telephone company provided “pair gain” systems and channel banks, sometimes things can be a little different. Odd voltages, strange feature implementations and other issues can cause problems with audio performance and produce weird behavior. Fortunately these kinds of interfaces keep getting better, meaning that the Hx will probably “just work”, with a few possible exceptions.
Hx Hybrid DB-9 PIN 5 (#1 hybrid off) 9 (#1 hybrid on) 6 (Ground) 4 (#2 hybrid off) 3 (#2 hybrid on) Connect to a Telos Direct Interface Module Using the Hx, or any hybrid supporting disconnect supervision with the Direct Interface Module (DIM) requires an external source of loop current. The DIM provides only a “dry” transformer audio feed which worked well with the simpler hybrids of the time. Visit the Telos website or contact support for several options that will allow you to use the Hx with the DIM. Connect to other systems? Contact Telos Support Telos collects and shares what we learn about “real world” telephony with our customers. Our...
InStallatIon | 15 present on the device feeding the Hx SEND IN. The goal of a proper mix minus is to prevent the hybrid from ‘hearing itself ’. 2.9 Power Input and Grounding Safety The AC input connects mains power to the unit with a standard IEC power cord. The power supply has a universal AC input, accepting a range from 100 to 240 VAC, 50-60 Hz, at 0.075 – 0.15 Amps. IMPORTANT SAFETY INFORMATION Surge Protection Precautions should be taken to prevent damage caused by power surges. WARNING The Hx1 and Hx2 use a universal-input power supply, which has an internal fuse. Hazardous voltages may still be present on some of the primary parts even when the fuse has blown. The power cord is the primary disconnect mechanism. Mains power should be near the equip- ment and easily accessible. The unit should not be positioned such that access to the power cord is impaired. If the unit is incorporated into a rack, an easily accessible safety disconnect device should be included in the rack design. Grounding This equipment is designed to be operated from a power source which includes a third ground- ing connection in addition to the power leads. Do not defeat this safety feature. In addition to creating a potentially hazardous situation, defeating this safety ground will prevent the internal line noise filter from functioning. Should you replace the power supply module in the future, be sure to re-connect the safety ground wires as shown in the illustration below. Inside the chassis near the power inlet is a ground stud. The ground wire from the power inlet is attached to the ground stud with a star washer on either side of the wire terminal. (See above figure). A nut is used to independently tighten the inlet ground wire to the chassis. Next, the ground wire from the power supply is fastened to the ground stud with a star washer on either side of the wire terminal. An additional nut is fastened to the top of the ground stud.
| 17 Operation 3.1 Front Panel Buttons There is a column of three pushbutton switches on the Front Panel for each hybrid. Hybrid ON Caller ON-HOLD Hybrid OFF 3.2 Line Status Display The Line Status display on the Front Panel shows the state of the phone line in iconic form. The Status Symbol icons displayed on the LED matrix in normal operating mode are as follows: Line is ready for incoming or outgoing calls Line not detected Line is ringing...
18 | Section 3 Call is ON-AIR Call is ON-HOLD If the Line Status display indicates “Line not detected” after power-up, the telephone line is not connected to the LINE jack on the back Panel, or line voltage is not detected. Check your wir- ing and verify that dial tone is present on the line. This function is not compatible with ground start lines or trunks as these do not have loop current or voltage present until the line has been grounded momentarily or is ringing. 3.3 Metering Each hybrid has its own SND and RCV meters to simultaneously display the studio input audio level, as well as the output level of the caller. Set the input level pot so that 0dbu on your console causes the Hx to display a yellow bar on the SND bargraph. The meter displays audio before any processing. The output meter indicates audio levels after all processing and EQ. It’s also useful for trouble- shooting mix minus and other audio issues. A yellow bar corresponds to +4dbu at the audio output. The nominal output level is fixed at +4dbu. Each hybrid also has a pair of EQ meters which show that amount of gain adjustment applied to the incoming caller audio in HI and LO frequency bands. When the DDEQ feature is disabled via the Back Panel DIP switch settings, nothing will appear on the EQ HI and EQ LO bar graphs.
OperatiOn | 19 3.4 Basic Operation You can use a telephone set to either dial an outgoing call or to talk to an incoming caller before they are switched to the hybrid. When a call is ringing-in, the line status icon will display expanding concentric squares. Push the button to answer it directly on the hybrid or use the telephone set to speak with the caller. You can move the call from the telephone to the hybrid by pressing the button. The telephone set will be disconnected. When a call is taken on the hybrid, a brief mute/adapt period provides an opportunity for the system to adapt to the line before the call goes on the air. The caller hears a “noise burst” to alert him that he’s on the air but the noise burst isn’t heard by the audience as the output is muted while the noise is being sent. While the caller is on the hybrid, the hybrid continuously adapts to telephone line characteristics. Press the button to return the call to the telephone handset and disconnect it from the hybrid. Hang up the phone if you want to drop the call. When a call is active on the hybrid, pressing the button mutes the receive audio, but keeps the call active on the hybrid. The caller hears send audio while waiting on hold and the unit will disconnect if the held caller hangs up or is disconnected for any reason. When a call is on hold and you press the button, the caller audio is restored. The caller will hear the adapt noise/ tone, about half the length of when you press the button from any other condition. Thus, one purpose of the Hold function is to allow a “pre-adaption” to the telephone line and a quick take of it later.
| 21 Configuration Settings Configuration of the Hx is done via DIP switch settings. There’s a quick reference guide in the back of this book that lists the remote connector pin numbers and all of the available configura- tion options and their switch settings. You’ll probably use those two pages more than anything else in this manual. There’s also a diagram at the end of this section that shows inputs, outputs, controls and metering points. A picture is worth a thousand words, maybe more when you’re in a hurry. Before we lose you to the “quick reference guide” we should point out that here we provide the details that you might need to set up your Hx most effectively. If this is your first Hx, a few minutes with this section will help you determine which features will help you in your particular application. Send Audio Processing The Hx1 and Hx2 hybrid’s send-to-caller audio processing consists of the following functions: Sample rate conversion ♦ High-pass filter ♦ Anti-Feedback - the “pitch” shifter and Acoustic Echo Canceler ♦ Send AGC/Limiter ♦ Sample Rate Conversion AES and analog input sources are sample rate converted to the hybrid’s internal sampling rate of 8 KHz. High-Pass filter A high pass filter with a 300 Hz break frequency improves hybrid performance and enhances intelligibility by removing unnecessary low frequencies from the input audio. This function is always enabled. Send Automatic Gain Control / Limiter The AGC helps maintain consistent audio levels to the caller. This function is always enabled. At...
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22 | Section 4 Receive Audio Processing The Hx1 and Hx2 hybrid’s receive audio processing consists of the following functions: High-pass “hum” filter ♦ Adaptive Echo Cancellation ♦ Automatic Gain Control ♦ Noise Gate ♦ Digital Dynamic Equalization ♦ Sample rate conversion ♦ High-pass “hum” Filter This filter removes hum and other unwanted low frequency noise from the caller audio. This filter has a break frequency of 100 Hz. Adaptive Echo Cancellation An adaptive filter removes studio send audio from the received caller audio. It adapts continu- ously and naturally. Receive Automatic Gain Control The Hx’s smart gated AGC improves the consistency of the caller’s audio level delivered to the studio console, without audible processing ‘artifacts’ . An important additional feature of this AGC is that it is cross-coupled to other sections of the hybrids and can therefore reliably distinguish between caller audio and hybrid leakage. This allows a more aggressive gain control for bringing up low-level callers while still preserving excellent hybrid performance.
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CONFIGURATION SETTINGS | 23 Ducking System The ducking function serves several purposes: Provides “aesthetic” control over the caller that many programmers prefer. Allows the ♦ announcer to “override” the caller in a way that sounds natural and appropriate. Reduces feedback when the Hx is used like a speakerphone in an “open ♦ loudspeaker’”situation. Dynamically improves effective trans-hybrid loss to reduce leakage, when necessary. ♦ When used, the Hx inserts a controlled loss (ducking) into whichever audio path (send or receive) is not active at the moment. When the caller is speaking, this loss is inserted in the announcer path, and when the announcer is speaking, the caller gain is reduced. The effect is “seesaw-like”. Normally, the gain reduction is symmetrical, but, if Feedback Reduction is enabled, the hybrid will have more ducking in the announcer-to-caller direction. You’ll probably need more ducking when using an open loudspeaker. As noted above, ducking helps prevent feedback and reduces echo returned to the caller. You can select how much of this effect you prefer, from Half Duplex, which makes the hybrid operate like a ‘one-way-at-a-time’ speakerphone, to Full Duplex (0dB) which disables ducking altogether. The default is –6 dB. Signal Flow and Audio Processing The above figure illustrates the signal processing chain in both the SEND input to the caller, as well as the caller receive to RCV output path. The Ducker is involved in both processing paths. The figure also shows which processing stages that you can adjust via the SETTINGS and OP- TIONS bank of DIP switches in the rear of the hybrid unit. See Section 4.1 for further details regarding the DIP switch settings.
24 | Section 4 4.1 Rear Panel DIP Switch Control On the rear panel of the Hx1 and Hx2 chassis there are two banks of DIP switches labeled SETTINGS and OPTIONS. The SETTINGS bank of DIP switches (SW1) allows you to control the operational levels of various signal processing stages of the hybrid unit. The OP- TIONS bank of DIP switches (SW2) allows you to configure the operation of various features of the hybrid. The two tables below show how the individual DIP switches are allocated on each bank. SETTINGS Function Bits 1 and 2 EQ LO, fixed dB gain adjustment Bits 3 and 4 EQ HI, fixed dB gain adjustment Bits 5 and 6...
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CONFIGURATION SETTINGS | 25 Bit 1 Bit 2 Configuration Setting Value Adapt + Fixed EQ (Use SETTING Bits #1, 2, 3, 4 to set the Fixed levels) You can separately specify the level of adjustment in the EQ HI and EQ LO frequency bands when the DDEQ mode is configured for Fixed EQ mode. SETTINGS Bits #1 and #2 control the dB adjustment for the EQ HI band, and Bits #3 and #4 control the dB adjustment for the EQ LO band as follows: SETTINGS Bit 1 Bit 2 Configuration Setting Value 0 dB adjustment, EQ LO [Factory Default] +2 dB adjustment, EQ LO +4 dB adjustment, EQ LO...
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Auto-Answer = ON, Auto-answer after first ring Auto-Answer = ON Auto-answer after third ring Auto-Answer = ON Auto-answer after eighth ring Send extra gain to caller configuration setting The Hx1 and Hx2 hybrid units have been designed to send a -9 dBu average level to the telephone line, to meet the USA’s FCC regulations. OPTION Bit #5 adds 3dB of gain to the send level heard by the caller. This should only be used when the hybrid is connected to a PBX or in countries outside of the USA that permit a higher transmit level. OPTIONS Bit 5 Configuration Setting Value No additional gain is applied...
CONFIGURATION SETTINGS | 27 Hx2 Internal Mix-Minus Configuration setting The Hx2 can operate as two independent hybrids or be configured to perform an internal mix- minus between the two hybrids. OPTIONS Bit 6 Configuration Setting Value Independent: Internal mix-minus is disabled. [Factory Default] Coupled: Internal mix-minus is enabled. Feedback Reduction enable The Hx 1 and Hx2 has an optional Acoustic Echo Canceler in the Studio send path. This can be used when there is acoustic coupling between a loudspeaker connected to the hybrid output and a microphone connected to the input. Enabling feedback reduction also causes the ducker to insert more loss into the announcer-to-caller direction when the caller is dominant. OPTIONS Bit 7 Configuration Setting Value Acoustic Echo Canceler is disabled [Factory Default] Acoustic Echo Canceler is enabled (use in “open speaker”...
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28 | Section 4 The internal DIP switch bank is divided up into two subsets of 4 switches each: Bits #1 through 4 configure the Hx’s telephone interface circuitry to match the telephone ♦ line impedance and voltage characteristics of the country where the hybrid is used. Bits #5 through 8 configure Call Progress Tone Detection to match the call progress ♦ tones used by various countries or central office switches. Call progress tones (Dial tone, busy tone, etc) can be used to make the Hx disconnect when loop current signaling is not available or is unreliable. Call Progress Tone Disconnect is active only on Auto-Answered incoming calls to prevent undesired disconnections. It may be disabled if the feature causes problems in your application. See internal DIP switch settings table below. Table 1 lists what telephone network characteristics are being selected by Bits #1 through 4. Table 2 lists the Call Progress Tone Detection characteristics being selected by Bits #5 through 8. Table 3 lists the recommended DIP switch settings for each country. Reorder tone is a “fast busy” signal often used to indicate network congestion or error conditions. Table 1 - Internal DIP Switch bank Bit 1 Bit 2 Bit 3 Bit 4 Telephone Network USA, Canada Japan, low voltage networks FCC compliant countries CRT21, Europe (real line impedance) Custom country configuration...
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CONFIGURATION SETTINGS | 29 Bit 1 Bit 2 Bit 3 Bit 4 Telephone Network Custom country configuration Custom country configuration Reserved for future use Reserved Reserved Reserved Reserved TABLE 2 – Internal DIP Switch bank Bit 5 Bit 6 Bit 7 Bit 8 CPTD Signal characteristics US dial tone...
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30 | Section 4 Country Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 Canada Chile China Colombia Croatia CTR21 Cyprus Czech Repub Denmark Ecuador Egypt El Salvador Finland France Germany Greece Guam Hong Kong Hungary Iceland India...
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CONFIGURATION SETTINGS | 31 Country Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 Pakistan Peru OFF z Philippines Poland Portugal Romania Russia Saudi Arabia Singapore Slovakia Slovenia South Africa South Korea Spain Sweden Switzerland Syria Taiwan...
32 | Section 4 Factory Default Configuration Settings These settings will work in most cases and should be considered to be a “starting point”. The following is the Factory Default Configuration for the SETTINGS, OPTIONS, and Internal Telephone Network/Call Progress Tone Detection (CPTD) DIP switches: Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 SETTINGS Bits 1 and 2 EQ LO, fixed dB gain adjustment => 0 dB gain Bits 3 and 4 EQ HI, fixed dB gain adjustment =>...
| 33 AES I/O OPTION 5.1 Installation Instructions The Hx1 and Hx2 hybrid units can be purchased with the optional AES I/O module pre- installed, or as an upgrade kit to be installed in the field. The AES board Upgrade Kit [2011- 00068] includes the following items: 1701-00149-100 ( Qty =1) AES Board assembly 1308-00023-100 ( Qty =2) board standoff, M3x10mm, MF 1301-00077-100 ( Qty =2) screw, M3x6mm Phillips Pan-Head steel zinc The following instructions explain the steps to install the AES I/O module onto the mother- board using the upgrade kit. Chassis cover removal and upgrade kit installation should only be performed by a qualified technician or engineer. 1. AC power must be disconnected prior to removing the chassis cover. Remove the AC power cable from the power inlet in the back of the hybrid unit. 2. Remove the 10 Phillips screws that mount the top cover to the hybrid chassis.
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34 | Section 5 hole located below capacitor C137. 5. Align connectors JR2 and JR1 on the AES plug-in module with JP4 and JP3 on the motherboard. Likewise, align connector JP1 on the plug-in module with JP5 on the motherboard. (See figure below). Push firmly to seat the plug-in module onto the moth- erboard. Visually confirm that connector JR2 fits onto all four sets of pins on JP4, and JR1 connector fits onto all four sets of pins on JP3. 6. Take the two mounting screws from the kit (1301-00077-100) and install them into the female side of the board standoffs in order to secure the AES I/O module to the hybrid motherboard. 7. Reinstall the top cover using the 10 Phillips screws. 8. Plug the AC power cord back into the socket and wait for the unit to power up. The hybrid unit will automatically detect the presence of the AES plug-in module, and directly trans- mit and receive digital data at the clock rate of the AES source plugged into the SEND IN XLR input connector. 9. You can use the built-in diagnostic mode of the hybrid unit to confirm that the AES I/O module is working properly. Refer to Section 6 of the User’s Manual for instructions on how to enter this mode of operation. Test “T2” is a loopback test that takes audio present...
AES I/O OPTION | 35 at the SEND IN XLR connector and loops it back to the RCV OUT XLR connector unprocessed. The input signal and output signal levels are also displayed on the Front Panel SND and RCV LED bar graph meters. 5.2 AES Channel Assignment The studio input signal should be on the LEFT AES channel feeding the SEND IN XLR connector. The studio output signal is present on the LEFT AES channel on the RCV OUT XLR connector. When the two hybrids are operating independently (internal mix-minus mode is disabled), the separate studio input signals should be on the LEFT AES channel being fed into the respective SEND IN #1 and SEND IN #2 XLR connectors. The studio output signals will be brought out separately on the LEFT AES channel on the respective RCV OUT #1 and RCV OUT #2 XLR connectors. When the internal mix-minus mode is enabled on the Hx2 hybrid unit, only the LEFT AES channel being fed into SEND IN #1 is used as the studio input signal to BOTH hybrids. The studio output signals are brought out separately on the LEFT AES channel on the respective RCV OUT #1 and RCV OUT #2 XLR connectors. 5.3 Restoring an AES equipped unit to analog operation 1. With power removed, remove the unit cover and the two mounting screws that fasten the AES daughter board to the main board. 2. Remove and store the AES daughter board. 3. Install 2 sets of four jumpers each on JP3 and JP4 locations on the main board. Analog audio will now be present on the rear panel XLR connectors. 4. Replace cover and verify proper operation.
| 37 Troubleshooting 6.1 On-board Diagnostics Pressing and holding the button for 3 seconds puts the unit into a self-diagnostic mode. When the unit is in diagnostic mode, the Line Status display shows the current diagnostic state. This mode is only intended to provide status information, and to confirm if the hybrid unit is operational.
38 | Section 6 bank are set to the OFF position for Factor Default setting, thus no LEDs are lit on the EQ LO meter). 6.1.3 T1 Test - 400 Hz Tone Generation Press the hybrid button to advance to the next diagnostic test. The Line Status display should indicate ‘T1’.
TroubleShooTing | 39 6.1.5 T3 Test - Feed Through Test Press the button to advance to the next diagnostic test. The Line Status display should indicate ‘T3’. This test takes audio present at the SEND IN XLR connector and feeds it to the LINE RJ11 connector without any processing.
| 41 Specifications 7.0 Specifications ANALOG INPUTS Send Analog Inputs 1 for Hx1, 2 for Hx2 (one per hybrid) Connector XLR Female, Pin 2 High (Active Balanced, RF Suppressed) Input Range Selectable between MIC and LINE levels Line Input Level Adjustable from -10 to +8 dBu Impedance Bridging > 50 K Ohms Analog Clip Point +21 dBu A/D Converter Resolution 24 bits ANALOG OUTPUTS Receive Analog Outputs 1 for Hx1, 2 for Hx2 (one per hybrid) Connector XLR Male, Pin 3 High (Active Balanced, RF Suppressed) Output Level Nominal +4 dBu, fixed Impedance < 50 Ohms D/A Converter Resolution 24 bits Headroom Before Clipping 20 dB headroom from +4 dBu nominal levels AUDIO PERFORMANCE Frequency Response 200 to 3400 Hz, +/- 1 dB THD+N/Input < 0.5% THD+N using 1 KHz sine wave...
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42 | Section 7 Rate Conversion Sample Rate Converters on all inputs and outputs. Inputs can accept 32, 44.1, and 48 KHz rates. Clock for outputs may be sourced from the AES inputs or internally-generated at 48 KHz Input Level Nominal at -20 dBFs Output Level Nominal at -20 dBFs...
Systems (hereinafter “Telos Systems”). With the exception of software-only items, the Products are warranted to be free from defects in material and workmanship for a period of one year from the date of receipt by the end-user. Software-only items are warranted to be free from defects in material and workmanship for a period of 90 days from the date of receipt by the end-user. This warranty is void if the Product is subject to Acts of God, including (without limitation) lightning; improper installation or misuse, including (without limitation) the failure to use telephone and power line surge protection devices; accident; neglect or damage. EXCEPT FOR THE ABOVE-STATED WARRANTY, TELOS SYSTEMS MAKES NO WARRANTIES, EXPRESS OR IMPLIED (INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE). In no event will Telos Systems, its employees, agents or authorized dealers be liable for inciden- tal or consequential damages, or for loss, damage, or expense directly or indirectly arising from the use of any Product or the inability to use any Product either separately or in combination with other equipment or materials, or from any other cause. In order to invoke this Warranty, notice of a warranty claim must be received by Telos Systems within the above-stated warranty period and warranty coverage must be authorized by Telos Systems. If Telos Systems authorizes the performance of warranty service, the defective Product...
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September 2010. It will be outdated by the time the ink is dry. The Telos website (http://www.telos-systems.com) is your best source of up to date informa- tion about broadcast telephony. The terms here are mainly related to Access Technologies and broadcast industry telephony common at the time of writing.
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A2 | appendix 1 ATA – see Analog Terminal Adapter. B8ZS- Bipolar 8 (with) Zero Substitution. A T1 line coding method. This is the more modern and most common line coding method of the two commonly available. See Line Coding, T1. See also AMI.
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This includes dial tone, ring back tone, re-order (or fast busy) tone, Special Information Tones (SIT’s), etc. The Telos Hx can be set to listen for these tones and disconnect when one is heard if CPC is not available or is unreliable.
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A4 | appendix 1 Unless very aggressive contesting is planned, these arrangements should probably best be avoided. See blocking and concentration. Circuit- A physical path through which electrical signals can pass. It consists of a network of conductors and other components, separated by insulators. Technically this term cannot be applied to fiber optic or other “non-metallic”...
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telephone terminology guide | A5 BRI or PRI channels as well. Each combination trunk normally has a telephone number, although they are frequently part of a hunt group and only one number may be published for that group. Also called a Both Way Trunk. This is not the same as a Two-way DID trunk. See DID trunk, Hunt Group and Trunk.
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A6 | appendix 1 DID Extension or DID station - A specific phone within a PBX which can be called from the public telephone network without going through an attendant or auto-attendant. DID Number- A phone number used to route calls from the telephone network to a specific phone in a PBX (the DID extension).
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telephone terminology guide | A7 DSLAM – Central Office or wire center based Digital Subscriber Line Access Multiplexer. What’s on the “other end” of your DSL line. These are sometimes fed by HICAP (High Capac- ity or Fiber) facilities to remote wire centers (“remotes” or “vaults”) where “Pair Gain” (carrier) systems reside, so that DSL service may be provided to customers who otherwise could not be served due to loop length limitations.
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While this task is theoretically quite simple, the fact the impedance of most phone lines varies widely across frequency complicates matters. The Telos 10 telephone system was the first practical DSP based hybrid and applied the then brand-new technology to this problem.
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telephone terminology guide | A9 ILEC – Incumbent Local Exchange Carrier. A local Exchange Carrier which entered the marketplace before the enactment of the 1996 Telecom act;. i.e. a telephone company which is neither an Indi nor an RBOC. See LEC and CLEC. IMUX –...
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A10 | appendix 1 and LECs are beginning to be permitted to handle InterLATA calls. LDN- Listed Directory Number. When a number of Telco channels share the same hunt group, it is customary to give out only one phone number for the group, although generally each channel will have its own number.
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telephone terminology guide | A11 Loop- The telephone circuit from the CO to the customers premises. Generally refers to a copper cable circuit. Loop Current Disconnect Supervision - Another name for CPC. See CPC. Loop Qualification- Process of actually measuring the loss on a prospective ISDN line to see if it can be used for ISDN service.
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Decodes from the line’s 2B1Q coding scheme. The customer end of the NT1 interfaces using the “S” or “T” interface. The NT1 is frequently part of the “Terminal Adapter” and is built-in to Zephyr Xstream, Zephyr, ZephyrExpress, Telos TWO and TWOx12 systems sold in the USA & Canada. See also NCTE.
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telephone terminology guide | A13 physical interface between a Switch and a Line or Trunk or “line equipment”. Product literature often refers to the number of ports on a phone system. In this context it refers to the number of phones or lines (or sometimes the combination) the system supports. POT- Plain Old Telephone.
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A14 | appendix 1 amount of current to be passed through a telecom circuit for purposes of “healing” resistive faults caused by corrosion. Bellcore specifies sealing current on the ISDN U interface in the USA. The Siemens EWSD switch does not provide sealing current. Most other ISDN capable switches used in North America do.
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SAIC in 1997. Telcordia is responsive to both RBOCs and independent Telcos. Their web site is: http://www.telcordia.com. See GR-303. Telephone Number- See DN and MSN. Telos Customer Support +1.216.622.0247. Available 24 hours a day, every day. You may also ask for assistance by emailing to Support@telos-systems.com.
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No hybrid is perfect, and those used by the phone company can be poor. However, the hybrids in Telos Hx units are approaching perfection! USOC – Universal Service Order Code, The Bell System Universal Service Ordering Code (USOC) system was developed to connect customer premises equipment to the public network. ...
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telephone terminology guide | A17 Virtual ISDN- An alternative to repeaters which uses a local Telco Switch to act as a repeater and which then sends the signal onto another switch which supports ISDN. See also Repeater. VoIP – Voice over Internet Protocol, communications services that are transported via packet switched IP networks, rather than the public switched telephone network (PSTN).
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APPENDIX 2 | QUICK REFERENCE GUIDE: REAR PANEL SWITCHES | A19 | Quick Reference Guide: Rear Panel Switches SETTINGS Function Bits 1 and 2 EQ LO, fixed dB gain adjustment OFF OFF 0 dB adjustment, EQ LO [Factory Default] OFF ON +2 dB adjustment, EQ LO ON OFF +4 dB adjustment, EQ LO ON ON +6 dB adjustment, EQ LO Bits 3 and 4...
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A20 | Appendix 2 OPTIONS Function Bits 1 and 2 DDEQ configuration OFF OFF DDEQ feature is turned OFF OFF ON Fixed EQ mode (Use SETTING Bits #1, 2, 3, 4 to set the levels) Adaptive EQ mode [Factory Default] ON OFF ON ON Adapt + Fixed EQ (Use SETTING Bits #1, 2, 3, 4 to set the Fixed levels) Bits 3 and 4...
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Appendix 3 | Quick reference guide: internAl switches & remote connector pin usgAe | 21 | Quick reference guide: internal switches & remote connector pin usage Internal DIP Switch bank: Line Voltages and Impedance Bit 1 Bit 2 Bit 3 Bit 4 Telephone Network USA, Canada Japan, low voltage networks FCC compliant countries CRT21, Europe (real line impedance) Custom country configuration Custom country configuration Custom country configuration Europe (complex line impedance)
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22 | Appendix 3 Bit 5 Bit 6 Bit 7 Bit 8 CPTD Signal characteristics Reserved Reserved Call Progress Tone Detection (CPTD) feature is disabled REMOTE connector pin usage Direction Unit Function GPIO Ground GPIO Input Hybrid #1 Hybrid ON GPIO Input Hybrid #1 Hybrid OFF GPIO Input...
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