Section 1 — General Information

(original pages 1-23)

1.1 Introduction

This manual contains general, installation, operation and maintenance information for the Dynamax CTR100 Series of Cartridge Recorders/Reproducers.

Section 1 is a general description of the CTR100 features, specifications, warranty and service information.

1.2 General Description

1.2.1 Exclusive Features

The Dynamax CTR100 Series represents the most advanced state-of-the-art development in audio tape cartridge recorders/reproducers.

Four models of the CTR100 are available:
Models Description
CTR111 A Size Mono Play
CTR112 A Size Stereo Play
CTR123 B Size Mono Record/Play
CTR124 B Size Stereo Record/Play

CTR innovations include:


    Automatically, without operator intervention, enables the intermixing of cartridges recorded at elevated or standard level using mono, stereo or matrix stereo and activates a cartridge-triggered auxiliary output to control equipment such as Dolby or dbx encoder or decoder.

    The system is activated by a special optically encoded label which is placed along the right edge of the cartridge prior to recording. The record machine reads the label and records the cartridge in the indicated format. Later, during playback, the reproducer reads the label and properly reproduces the cartridge.

    The CARTSCAN System permits you to perform the following operations:
    1. Easy conversion from mono to stereo.
      Previously recorded mono cartridges may be intermixed with new recorded stereo cartridges. The CTR100 will automatically output an identical mono signal to the left and right outputs when a mono cartridge is played on a stereo machine.
    2. Utilization of cartridges loaded with High-Output Low-Noise (HOLN) tape.
      The elevated level mode allows specific cartridges to be automatically recorded up to 8 dB higher in level (at “0” VU) than standard cartridges, resulting in an equivalent improvement in signal to noise. Standard and elevated level cartridges may be intermixed. The CTR100 will automatically normalize the levels.
    3. Elimination of cartridge phasing problems by use of the stereo matrix mode.
      By recording the mono sum of left and right inputs (L+R) onto the left record track, and the difference (L-R) on the right record track, and then recombining the signals during playback, a stereo signal will result without cartridge induced phase errors. Normal discrete stereo or matrix stereo cartridges may be intermixed.
    4. Cartridge-triggered activation of auxiliary equipment.
      The cartridge user who wants to use noise reduction on certain cartridges can utilize the AUXiliary CARTSCAN function which provides a logic output at the remote connector. Similarly, inserting a specific cartridge can cause a remote function to occur; i.e., switching on EBS equipment, network joining, tally light actuation, etc.

    Playback tape speed may be continuously varied over a plus or minus 30% range as cue tone sensors track motor speed to provide proper tone detection. This allows cartridges to be played uptempo or downtempo, or to be shortened or lengthened with respect to play time. Pitch control and special effects are also possible. VARY SPEED enables the cartridge machine to be interlocked with another machine using an SMPTE controller. In this mode, the speed can be varied continuously from 1.875 to 30 i.p.s.


    Referenced to the motor tachometer, unlike the conventional fixed reference used in other machines. The timer accelerates or decelerates with the tape and always displays the total elapsed time regardless of tape speed. This system provides accurate message timing and the ability to locate rapidly and accurately a specific point on the tape.


    Located just inside the cartridge opening, this switch permits the pinch roller solenoid to be activated without inserting a cartridge, allowing the pressure roller to be cleaned from the front of the machine.


    The head bridge mounts to the transport with three screws. Locks are provided for the height and zenith adjustments. Azimuth adjustment does not affect height or zenith. The front surface of the bridge provides flat and precisely vertical reference to the cartridge. There are no screws along the front cartridge reference surface. This design provides for precise head penetration. The head bridge incorporates micro adjustable tape guides with vernier self-locking height adjustment screws.


    Four molded rubber rollers place downward pressure on the upper edges of the cartridge Their canted design helps insure that the cartridge is aligned along the right cartridge guide. The flat and vertical front reference surface of the head bridge permits the cartridge to align squarely.


    Transfers only necessary information to the operator. Indicates status of AUDIO Switcher, VARY SPEED, SERVO ERROR, 1 KHZ DEFEAT and AUXiliary Output.


    Indicates status of all CARTSCAN functions.

1.2.2 Standard Features

The CTR100 provides a number of additional features never before available in one cartridge machine.

  1. Front Panel Machine Status Display
  2. DC Servo Drive Motor
  3. Fast Forward Wind
  4. Secondary and Tertiary Cue Tones
  5. Low Voltage Constant Current Solenoid
  6. Audio Switcher
  7. Audio Transformerless Circuitry
  8. 150 Hz Turn Off of Audio Switcher (Strappable)
  9. 150 Hz Initiation of Fast Forward (Strappable)
  10. 150 Hz Freeze of Digital Timer (Strappable)
  11. Constant Current, Group Delay Compensated Record Amplifier
  12. Separate Low Frequency and High Frequency Playback Equalization controls
  13. Crystal Referenced Oscillator for Servo Motor, Bias Oscillator, Cue Tone Sensors and Cue Tone Generators
  14. Front Panel 1 kHz Tone Add and Defeat
  15. Full Metering with Automatic Record/Play Changeover
  16. Two Speed “Played” Flashing Indicator
  17. “Played” Restart Disable
  18. Active Bias and Signal Mixing
  19. Bar Graph LED Level Indicators
  20. Improved Heads for Flat Low Frequency Response, Low Noise
  21. Built In Test Oscillator
  22. Splice Finder
  23. Fast Forward Audio Un-Mute Control
  24. Ball-Bearing Self-Aligning Pressure Roller
  25. Trouble-Free Vapor Honed Stainless Steel Capstan
  26. Status Lamp Flash Synchronizer

1.2.3 Electronics

The electronics utilize mother/daughter board construction eliminating the need for a wiring harness. The solenoid, motor and power transformer are also connectorized to facilitate servicing. Circuit boards are G10 fiberglass epoxy with gold plated fingers. In addition, the circuit board connectors are gold plated. All integrated circuits are socketed for easy servicing. The state-of-the-art electronic components utilized in the audio circuitry provide excellent noise, transient response and dynamic range performance. The playback preamplifier incorporates a flat response first stage which eliminates interaction between tape head loading and the playback equalizer. Low frequency and high frequency playback equalization controls are provided, allowing for optimization to any equalization standard. Differentially balanced transformerless outputs result in better frequency response, phase and transient performance.

The transformerless record circuits accept input levels as low as -17 dBm. The record bias and audio are actively summed eliminating the need for adjustable bias traps. The head drive circuit is unique and innovative. The tape head is always under constant current operation. It is a part of the feedback loop of the drivers.

The combination of the record head and special reproduce head produces frequency response comparable to that of an open reel recorder. The result is crisp, clean audio with excellent response, noise, transient, and distortion characteristics. The magnetic tape and cartridge becomes the only limiting factor.

1.2.4 Logic (Functional Description)

The logic circuitry utilizes CMOS devices resulting in low power consumption and excellent noise immunity.

  1. STOP Lamp
    Indicates whether a cartridge is ready to play (lamp stays on), has been played and cued up (lamp flashes slow), or has been manually stopped (lamp flashes fast). User selected jumpers can be used to inhibit the START switch when the STOP lamp is flashing.
  2. Secondary and Tertiary Cue Tones
    Standard feature. Front panel indicators illuminate when a tone is present. Logic and relay contacts are provided for remote tone sensing. All tones may be recorded in the RECORD or START mode.
    Standard feature. When initiated, the audio is muted automatically. Holding the FAST FORWARD button will unmute the audio. A user selected jumper may be used to initiate FAST FORWARD at the beginning or end of the Secondary tone.
  4. Variation of the D.C. Servo Motor Speed
    The speed may be continuously varied from 1.875 to 30 i.p.s. (or plus or minus 30% of the chosen standard speed in the playback mode when cue tone tracking is required). An oscillator with a center frequency of 9600 Hz must be connected to the remote control for VARY SPEED operation. A front panel indicator will illuminate indicating VARY SPEED.
  5. Front Panel SERVO ERROR Indicator
    When the motor is accelerating or decelerating, the SERVO ERROR indicator will illuminate. Will also illuminate when the motor is not operating at the correct speed and is out of servo lock.
  6. 1 kHz Stop Tone
    The tone will automatically be recorded at the beginning of a new recording. To defeat this function, press the RECORD switch twice prior to starting the machine. A front panel indicator will illuminate indicating a 1 KHZ DEFEAT. Additional stop tones may be recorded by pushing the RECORD button when the machine is in the START mode.
  7. Audio Switcher
    The AUDIO front panel indicator will illuminate when the START button is pushed. Entering any other mode of operation will turn off the Audio Switcher. The Audio Switcher remote control terminals from several machines may be interconnected allowing interaction between machines. Under this configuration, the last machine started would mute the audio output of all other machines.
  8. Real Time Digital Tape Timer
    Standard feature on record machines. This timer tracks the motor speed, accelerates and decelerates with the tape and always displays true tape time. A user-selected jumper may be used to freeze the timer at the beginning or end of the Secondary tone.
  9. Front Panel LED VU Meters
    The meters monitor the audio levels and may also be used to display left and right record bias, cue record bias and cue signals. There are four selectable modes of audio monitoring available:
    1. PLAY ONLY – meters show audio output continuously.
    2. RECORD ONLY – meters show record audio input continuously.
    3. AUTO I – meters show audio output and automatically switch to record input while in RECORD mode.
    4. AUTO II – meters show record input only when in RECORD and STOP mode (record ready). Automatically switch to audio output at all other times. This function allows the recording level to be preset and then automatically switches to give an off-the-tape indiction during the recording process.
    The meters may be switched to show either record input audio level or record head audio level after Mono and Matrix processing.
  10. CARTSCAN System
    CARTSCAN circuitry incorporates four infrared transmitter/ receivers mounted behind the right cartridge edge guide. These sensors read the optically encoded labels affixed to the right side of the cartridge and signal the machine to switch to the desired recording and reproducing format(s). The audio switching logic automatically responds to CARTSCAN System modes of recording/reproduction: MONO, STEREO, MATRIX and predetermined ELEVATED LEVELS. An AUXiliary sensor signals an external function such as Dolby encoding or decoding, etc.
  11. Built In Pressure Sensitive Splice Finder
  12. Built In Test Oscillator
    A 12-tone oscillator included in the record machine, in combination with the VU meters, permits maintenance without outboard test equipment.

1.2.5 Transport

The transport is constructed around a precision-machined ½ inch thick anodized aluminum deck plate for mechanical stability.

A heavy-duty two inch air damped solenoid is utilized with a chain driven pressure roller assembly. The solenoid is a low voltage device which is controlled with a two step constant current circuit. This circuit insures fast starts and then reduces and maintains solenoid current, providing constant pressure, regardless of line voltage fluctuations or solenoid duty cycle.

  1. Pressure Roller
    The assembly includes a ball-bearing race providing self alignment to the capstan shaft. This eliminates tape skew when the cartridge is first started, and eliminates keystoning due to roller wear or motor mispositioning.
  2. Motor
    The motor is a three phase hall effect direct drive DC servo device utilizing a precision non-magnetic stainless steel capstan shaft. The steel capstan eliminates the static and cleaning problems associated with ceramic capstans. The motor is controlled by a crystal referenced phase locked loop circuit providing excellent speed accuracy and low wow and flutter. Tape speeds of 3.75, 7.5 or 15 i.p.s. may be selected.
  3. Head Bridge
    Made from a precision three piece die-casting. The azimuth adjustment is independent of the height and zenith adjustments. Height and zenith adjustments are locked into position after setting.

    The tape guides are an integral part of the Head Bridge and may be precisely adjusted in the vertical plane by turning one screw for each guide. This design has eliminated the need for tape guide holding screws along the front of the Heao Bridge, resulting in an accurate front cartridge reference. The Head Bridge mounts to the transport with three screws and may be removed from the transport without upsetting previous head adjustments.

  4. Cartridge Positioning System
    This system is unique. It utilizes four molded rubber rollers in a canted design. These rollers place downward pressure on the cartridge edges and help to insure that the cartridge is aligned along the right cartridge edge guide. The familiar and often troublesome microswitch has been replaced with optical cartridge sensing.

1.2.6 CTR100 Specifications

  1. Power
    1. 117 VAC ± 10% / 234 VAC ± 10%
    2. 50/60 Hz
    3. 85 watts maximum
  2. Tape Speeds
    1. Standard Fast Forward Comment
      7.5 i.p.s. (19 cm/s) 22.5 i.p.s. (57 cm/s) Set by Factory
      3.75 i.p.s. (9.5 cm/s) 11.25 i.p.s. (28.5 cm/s) Strappable
      15 i.p.s.(38 cm/s) 30 i.p.s. (76 cm/s) Strappable
    2. Vary speed 1.875 to 30 i.p.s. as controlled by external oscillator
    3. 9600 Hz external reference will produce standard selected speed
    4. Cue tone sensors track motor speed (as varied by external oscillator) within plus or minus 30% of selected standard speed
    5. Vary speed feature is locked out in record mode
    6. Front panel vary speed indicator
  3. Capstan Motor Drive System
    1. Direct drive capstan
    2. Brushless 3 phase DC servo motor
    3. Electrolyzed stainless steel shaft/capstan non-magnetic
    4. Permanently lubricated ball-bearings
    5. Crystal referenced phase locked loop control
    6. Dynamic breaking from fast forward to normal speed
    7. Front panel servo error indicator
  4. Wow & Flutter
    Record/Play maximum
    0.12% DIN WTD at 7.5 i.p.s.
  5. Speed Accuracy
    Better than ± 0.2%
  6. Audio Output and Source Impedance
    Differentially balanced source impedance 400 ohms; RF bypassed
  7. Audio Output Level
    +20 dBm into 600 ohms before clipping
  8. Distortion
    Reproduce amplifier: 0.05% THD max 18 dB above 250 nWb/m

    System distortion, tape limited: 0.5% max 2nd or 3rd harmonic, 1 kHz, at 250 nWb/m
    1.0% THD max at 1 kHz

  9. Noise
    1. Signal/noise measured with bias/no signal at 7.5 i.p.s.
      Mono – 55 dB (minimum)
      Stereo – 53 dB (minimum)
    2. Hum and Noise – no tape
      Mono – 61 dB (minimum)
      Stereo – 59 dB (minimum)
    3. Squelch noise – 70 dB (minimum) measured over a 20-20 kHz bandwidth, reference 250 nWb/m at 1 kHz
  10. Cross Talk
    Within 50 dB minimum separation between program channels at 1 kHz
  11. Frequency Response
    ±2 dB 50 Hz - 16 kHz
  12. Equalization
    1. 1975 NAB EQ Standard normally supplied 7.5 i.p.s.
    2. IEC Standard on request (pot adjustment) 7.5 i.p.s.
    3. Field strappable for 1964 NAB EQ
    4. Adjustable low and high frequency playback EQ
    5. Adjustable high frequency record EQ
  13. Head Configuration
    NAB, Mono/Stereo
  14. Cue Signals
    1. NAB primary cue 1 kHz
    2. NAB secondary cue 150 Hz with front panel indicators
    3. NAB tertiary cue 8 kHz with front panel indicators
    4. Open collector sinking signal (ground switching) available upon sensing secondary or tertiary cue tones, 15 volts, 200 mA maximum, saturation less than 1V at 200 mA
    5. Open relay contacts available upon sensing secondary or tertiary cue tones (contacts close with tone present)
    6. Cue tone sensing over a plus or minus 30% speed variation in playback vary speed mode
  15. Logging Signals
    1. Not internal to machine
    2. Cue audio input, cue audio output and cue track bias control available for external use
    3. Output level .5V nominal from a logging signal of 35 nWb/m tape fluxivity
    4. Logging output impedance 1k ohms
    5. Cue audio input .5V nominal
    6. Input impedance 47k ohms
  16. Audio Input Level
    1. -17 dBm minimum input to record 160 nWb/m in normal mode, or up to 400 nWb/m in elevated level mode
    2. +20 dBm maximum input level, unbalanced input connection
    3. +26 dB~ maximum input level, balanced input connection
  17. Audio Input Configuration
    Differentially balanced bridging 10k ohms
  18. Metering
    1. Audio Metering, switch selectable
      1. Play only – monitors output level
      2. Record only – monitors record input level
      3. Auto 1 – monitors record input level when machine is in RECORD mode, automatically switches to output level at all other times
      4. Auto 2 – monitors record mode when machine is in RECORD and STOP (ready) mode, automatically switches to output level at all other times
    2. Test Metering
      1. Left program bias displayed on left meter; right program bias displayed on right meter
      2. Cue bias displayed on left meter; cue audio displayed on right meter
  19. Bias Oscillator
    144 kHz crystal generated
  20. Tape Capacity
    1. NAB sizes A and AA (CTR111 and CTR112)
    2. NAB sizes A and AA, B and BB (CTR123 and CTR124)
  21. Start Time
    Typically 100 milliseconds (timing dependent upon solenoid air damping adjustment)
  22. Stop Time
    Tape stop time typically 100 milliseconds (dependent on type and length of cartridge)
  23. Ambient Operating Temperature Range
    10-50 degrees Centigrade (50 degrees to 122 degrees Fahrenheit)
  24. Remote Control Signals
    1. All front panel controls and indicators (except record input controls and meters)
    2. Vary speed control and reference
    3. Cue track input, output and bias control
    4. Start, Stop and Cartridge Sense pulses for external timer
  25. External Connectors
    1. 9 pin “D” audio connectors (mating connectors supplied)
    2. 50 pin “D” – remote control
    3. Plug-in line cord
  26. Mounting
    1. Table top standard
    2. Rack mount (optional rack mount available)
  27. Ordering Information and Dimensions
    Model No. Description Dimensions
    Height Width Depth
    CTR111 A Size Mono Play 14.29 cm 15.24 cm 40.64 cm
    5.625 in. 6 in. 16 in.
    CTR112 A Size Stereo Play 14.29 cm 15.24 cm 40.64 cm
    5.625 in. 6 in. 16 in.
    CTR123 B Size Mono Record/Play 14.29 cm 22.23 cm 40.64 cm
    5.625 in. 8.75 in. 16 in.
    CTR124 B Size Stereo Record/Play 14.29 cm 22.23 cm 40.64 cm
    5.625 in. 8.75 in. 16 in.
  28. Shipping Information
    Model No. Shipping Weight Shipping Volume
    Pounds kg. cu. ft. cu. m.
    CTR111 30 13.6 1.4 0.04
    CTR112 30 13.6 1.4 0.04
    CTR123 35 15.9 1.8 0.05
    CTR124 35 15.9 1.8 0.05

1.2.7 2 Year Limited Warranty

Fidelipac Corporation warrants that new equipment sold is free of defects in workmanship or material for a period of two years from date of shipment. This warranty applies only to the original user and excludes wear items such as bulbs, fuses, heads, rollers, etc. Warranty cards should be accurately completed in full and returned promptly to Fidelipac in order to register each original user. If warranty cards are not properly filed with our offices, claims may not be recognized. Other manufacturers’ equipment, such as motors and heads, bear only those manufacturers’ standard warranty and no other warranty. Warranty claims will be honored only if written notice is received by Fidelipac within thirty days after discovery of a defect, and prior to return of equipment to us. Our only obligation will be to refund the purchase price, or, at our option, to replace or repair the item or part FOB the factory or other designated location. Returned equipment must be adequately packed and insured to protect against shipping damage and delivered to our factory by prepaid transportation for inspection and testing.

This warranty is limited to normal and correct use and service of equipment, and is not valid if defects result from maltreatment, exposure, excessive moisture or heat, or operation under environmental or other conditions apart from those prescribed in the equipment instruction manual. Moreover, this warranty will be void if equipment is altered or repaired without specific written authorization by Fidelipac.