MAXPRO Next generation 20W FM exciter board

Transcription

1 MAXPRO Next generation 20W FM exciter board The MAX PRO FM exciter is a complete redesign involving over 1000 man-hours of research and development. We have added an impressive number of new features such as power/swr readout on LCD, temperature readout on LCD, new easy connect Maxlink/I2C socket, improved silent cooling system, supply and external voltage readout on LCD, LCD-adjustable SWR/TEMP alarm with protection and many others! Innovative design provides for amazing unparalleled RF field immunity. Output power can be adjusted via on-board trimmer or LCD display. You can set precisely the power required to drive your amplifier.

2 Technical specifications: - RF output power: 0 to 25 Watts (25W max. 20W typical fully variable via LCD or trimmer) - Output connector: BNC, 50 Ohms - Frequency range: MHz ( for Japanese) - PLL steps: 5KHz (10/25/50/100/200KHz adjustable via LCD) - Frequency stability: +/- 20Hz - Spurious/Harmonic rejection: Harmonics: >50dB, Spurious: -90dB - Power supply: 11-15V/2.5A or car battery - Power connector: 2.1mm power socket, center (+) - Quartz locked PLL frequency control, ultra stable & clean output - Audio performance: Less than 0.2% distortion, 20Hz-75KHz - RF output ruggedness: SWR protection - Polarity protection, temp protection - Pre-emphasis, 50uS, 75uS or none selectable - Audio Input Impedance: 10Kohm, unbalanced, RCA jack - Audio Input Level: 0 db - S/N ratio: >90 db - PC Board Size: 100x125mm Features: - Displays power, reflected power, temperature, voltage and frequency on the LCD. - Extreme VCO isolation and RF field immunity (our exclusive innovative design) - SWR and TEMP protection with adjustable sensitivity - Power adjustment via LCD or trimmer - Frequency adjustment via LCD display or dip switches - Low PLL step (5KHz) - Can be setup via LCD to provide more power at band edges or band top/bottom - High power (15W typical) - True wideband no-tune operation - Directly supports our SE5000 DSP+ and SE3000+ stereo encoders via LCD MENU system - Improved cooling, galvanized full width heat sink disperses heat more effectively - MAXPRO3000+ does not pickup fan noise - MAXPRO3000+ power and swr (in watts) on the LCD - MAXPRO3000+ temperature, supply voltage, external voltage (0-50V) and audio level on the LCD - MAXPRO3000+ MaxLink connector for stereo encoder (no soldering) - MAXPRO V to 15V ( V is not required anymore for full power) - MAXPRO3000+ audio input is now more sensitive) - MAXPRO3000+ adjustable swr/temp alarm protection (via LCD) - MAXPRO3000+ supports reading PWR/SWR from external source, such as directional coupler (see manual) - Redesigned output low-pass filter

3 Additional Info: MaxPro can read output power from external directional coupler (swr/power meter). It will also show external power supply voltage up to about 60V; power supply for the additional amplifier). - You can now disable the welcome screen showing our company logo. Look at the LCD display and look for DWS solder jumper. Solder it and the welcome screen will not show. - Fan noise is now a thing of the past runs much cooler due to increased efficiency, better heat sink (runs across whole width of the board) and black-anodizing.

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5 3000+ EXCITER BOARD! A. Power ON/OFF switch, down = OFF, up = ON B. Optional power indicator LED can be connected here. This LED is also located on the LCD control module. C. Output RF power adjustment, active when Jumper (L) in position P2. Potentiometer can be installed instead of this trimmer. Use 5-10K. D. Optional ERROR indicator LED can be connected here. This LED is activated when RF output stage is NOT active. For example, whenever if temperature protection is activated, this LED illuminates and RF power is reduced. This LED is also located on the LCD control module. Important: This LED is also illuminated whenever you change frequency as the control unit turns RF power off until adjustments are finished. This does not signal a problem with temperature or SWR. E. Pre-emphasis. Use this jumper to set pre-emphasis. This can either be 50uS (EU and most of the world) or 75uS (USA). If you plan to connect stereo encoder to the MAXPRO3000+ board, place the jumper in position None (top - this disables preemphasis). F. The power and swr meter facility built into the MAXPRO3000+ can also read power from external sensor, which is a directional coupler, by setting these jumpers to ext position (both jumpers right) LCD shows output power from external directional coupler (swr/power meter). Accuracy can be set with two trimmers next to the solder pads (K and I). Solder pads between the trimmers are the voltage input from directional coupler, middle is ground as noted on the PCB. G. Audio input sensitivity adjustment. H. Audio input - RCA jack or MCX. I. See F J. Hardware SWR protection sensitivity adjustment. MAXPRO3000+ has hardware and software SWR protection, this trimmer sets the hardware SWR protection. Software protection could take too long to respond so we have a backup system in place. Low setting means that the protection trips very early, at a low SWR ration. This setting should normally be set close to maximum sensitivity (+). A poor antenna will trip this protection and transmitter will start powering down the output stage. Full power will be restored as soon as the SWR reduces. Change, if you think protection trips too early. This protection does not generate warning on LCD control unit, but error LED lights slightly depending on level of SWR. K. See F. L. This jumper selects the method of RF output power adjustment. It can either be LCD or trimmer P2. M. Soldering posts for a small 12V fan. Output stage appreciates a bit of air flow, it does not have to be substantial. As long as the air slowly moves a bit it'll be more than enough so use weakest available FAN. Due to improved design this fan now spins down completely at low RF power output and our new 40x40x25mm unit is almost completely inaudible even at highest speed. N. You can connect VU-1 led vu-meter unit here, it will show output power and swr as bar graphs. The 2 remaining bar graphs can be connected to SE5000 DSP+ and will show audio volume.

6 O. Connect external power supply voltage up to about 60V and LCD control unit will show the voltage; typically this would be power supply for the additional W amplifier. P. LCD control unit. If you want to control this unit with LCD, attach your LCD control module here. Q. Do not touch unless you understand what this is. This lets you fine-tune the reference frequency. Can be used to set the unit to any frequency, even though the PLL step is 5KHz. You can for example use this to set the frequency to KHz by first using the LCD to set it to KHz and than using this trimmer to shift it to Hz. R. I2C/Maxlink connector for easy connection with the SE5000 DSP+ stereo encoder. This lets you connect and control both units from the same LCD control units. Most of our Cyber Max FM units use this arrangement. This connection is now completely solder-free, just plug the connector in and voila, finished. Flat cable that runs between the units also carries supply voltage for the stereo encoder further reducing required wiring and work. S. 2.5A fast fuse. Always replace with this type for continued protection against shortcircuit. T. Power supply connector, center is positive. DO NOT use more than 15V. About 13-15V is necessary to get full power, but unit works well even as low as 11V and lower. Z. Output stage bias current. DO NOT touch unless you know what you re doing or unless you own a power meter. You can use this to increase or decrease maximum available power. For example, you can set your transmitter to 15W with LCD control units and than use this trimmer to reduce maximum power to 4W or 1W. LCD will than control your output power from 0 to 1W or from 0 to 4W as it won t be able to give more power due to reduced bias. Warning: This allows setting output power in excess of 20W. Damage may result so proceed with care. There is NO WARRANTY for output transistor, replacement final transistors are available at our website. X. DIP switches. These switches let you set frequency without LCD control unit. If you want to use LCD control unit, set all DIP switches to OFF. If you leave any switch in ON position, transmitter assumes that you want to use DIP switches and ignores LCD module commands (generating I2C errors on the LCD). W. RF output connection. BNC jack.

7 DESCRIPTION OF THE LCD CONTROL MODULE: LCD control module is self-explanatory, but let s make a quick summary. The three keys are up, down and menu. The green LED is power indicator and is always active. The other RED let signals that the output stage isn t active. This happens during these events: - When changing frequency or powering on before VCO has stabilized (normal) - When there is SWR or TEMP error condition You may have noticed two solder bridges, the DSW and lock keys. DWS disables the welcome message and our company logo. Bridge the solder pads to engage this function. The other solder bridge locks the keys and prevents the user from changing anything. This is an important feature that secures your equipment. Stereo encoder : MAXPRO3000+ directly supports SE3000 AN+ or SE5000 DSP+ stereo encoder. This makes it possible to set all audio parameters easily via LCD control module. SE5000 DSP+ comes with excellent DSP filters and 19KHz notch. Balanced inputs are an instant cure for most noise problems and this is why all professional installations usually take advantage of balanced inputs. APPENDIX A: USING THE MAXPRO3000+ Basically there are three push-buttons available for the menu system, UP, DOWN and MENU. By pushing UP or DOWN you get a shift of frequency in corresponding direction. Hold any of these keys for a few seconds and the frequency will increase by 500 KHz. The new frequency is saved automatically. The third button (MENU) gives you an option to set many of the DSP functions of this unit. LCD CONTROL MODULE MENU SYSTEM: POWER AND DSP FUNCTIONS It is possible to connect our SE3000 AN+ stereo encoder to MAXPRO The provided MaxLink header can be found on the RF board next to the LCD control unit s connector. The UP and DOWN keys are used to change parameter values. In normal mode the LCD simply shows the frequency and power or whatever view you select. Menu key can be used to enter the menu mode, repeatedly pressing this key brings up the following menus: RF POWER, STEREO MODE, VIEW SELECTION, TREBLE, BASS, COMPRESSION, THRESHOLD, ATTACK, DECAY, INTEGRATION, LCD CONTRAST, RIGHT CHANNEL GAIN, LEFT CHANNEL GAIN, PLL STEP, RF EQUILIZER, FIRMWARE VERSION, POWER SOURCE, TEMP ALARM and SWR ALARM. Pressing the UP or DOWN key selects the desired parameter and allows you to modify its value. Another press on the MENU key and you re back to normal mode.

8 CHANGING FREQUENCY Simply press the UP/DOWN button to change frequency. Depending on PLL STEP setting your frequency will go down in 5/10/25/50/100/200KHz steps. If you keep pressing a key for a while the PLL STEP switches to fast tuning mode and jumps in 500KHz steps. NOTE: Frequency changes also when you select a view type which does not show frequency, such as UPTIME. VIEW SELECTION MAXPRO3000+ is capable of displaying a number of various parameters. Since the LCD real-estate is limited to 2x16 characters we prepared a number of preprogrammed views that only show a selected number of parameters. Depending on your needs you can have the LCD show these: - Frequency - Set output power (bars, read RF POWER menu description below) - Measured output power (in watts) (internal and external) - Reflected output power (SWR) (internal and external) - Temperature of the final stage transistor - Supply voltage for MAXPRO External supply voltage, 0-60V, for power supply modules - Uptime (time from turning the unit on), usefull to determine power autages at the site, in days, hours and minutes. - Stereo/mono mode (ST or MO) - Audio level (view 4, if you are wondering, updates slow) We encourage you to try these out and see which suits you best. PLL STEP Frequency can normally be adjusted in smallest steps of 5KHz or larger steps of 10KHZ, 25KHz, 50KHz or 100KHz. We recommend you to select 100KHz as this lets you change frequency very fast. However, you can enter this menu and select a PLL step of 5 for example and take advantage of these small steps. RF POWER This setting allows you to set output power of MAXPRO Select desired power with the UP/DOWN keys and press MENU key to exit the menu system and return to normal operation. Selected power is displayed on the LCD as a line of bars. Note: If you select power adjustment via trimmer this setting does not work as you have to set power with P2 trimmer.

9 PRE-EMPHASIS Pre-emphasis is selected with a jumper. It should be set to either 50uS (standard for EU and most of the world) or 75uS (United states and Canada). When operating MAX PRO 3+ without stereo encoder, this should be done on the MAX PRO 3+ board. When using stereo encoder pre-emphasis should be disabled on the MAX PRO 3+ board and it should be set on the stereo encoder. There are two jumpers usually, correct position is marked on the board or check the manual of your stereo encoder. RF EQUILIZER This is a new revolutionary setting that lets you control how your transmitter rolls off at the band edges. Several settings are available and are represented by a graphic. Default setting tries to provide the same amount of power across the whole band. Another setting gives a slight power boost at the band edges around 88 and 108MHz helping flatten-out the frequency response of many RF amplifiers which tend to have lower output power and gain at the band edges. There are additional two settings, one of these gives more power at the top of the band around 108MHz and the other does the opposite, providing more gain at the bottom of the band around 88MHz. These four settings should cover any situation you are likely to encounter, whatever your amplifier s attitude might be. FIRMWARE This option allows you to display current LCD module firmware version. MONO/STEREO MODE SELECTION POWER SOURCE This is how you tell MAX PRO that you are going to use external directional coupler and power amplifier. By selecting External MAXPRO3000+ assumes that you set the J5 jumpers into external position and attached external power meter or directional coupler. Default setting is Internal and should not be changed unless you understand the above text. TEMP ALARM You can set the sensitivity of temperature alarm here. We recommend you set these to degrees celsius. A properly installed unit with a tiny fan will typically run at 55 degrees C at maximum output power. SWR ALARM You can set the sensitivity of software SWR alarm here.

10 AUDIO LEVEL ADJUSTMENT Adjust audio level with trimmer (P1) on the RF board. This prevents interference to adjacent channels as you probably do not own expensive audio equipment that radio stations usually employ to make their stations sound louder. Remember to disable pre-emphasis, if you re using a stereo encoder (usually a stereo encoder or limiter include their own pre-emphasis circuit). APPENDIX B: HOW CAN I INCREASE PERFORMANCE? I m pretty sure you are all interested in this, or at least you will be after a while. First let me warn you might have stability problems if you try to push MAX too far. You ll also have to account for additional heat. Here is a list of simple things you can do to raise output power of MAXPRO3000+: 1. Increase supply voltage to 14-15V APPENDIX E: CONNECTING SE5000 DSP+ OR SE3000 AN+ TO MAXPRO3000+ VIA MAXLINK BUS Control all parameters through the same LCD unit. This is a 6-wire flat cable that is simply plugged into appropriate IDC connector on stereo encoder board and the other end into MAXPRO3000+ or LCD control unit. See fig. 19 below for wiring directions (Scenario C). You don t have to wire a separate supply (12V) wire to the stereo encoder as the MaxLink cable delivers supply voltage as well. You still have to connect audio cable (MPX out to audio input of the MAXPRO3000+ exciter), but that is really easy to do. Stereo mode LED operation is simple, if illuminated, you are in STEREO mode.

11 Note: Remember to set the Auto/LCD jumper on the encoder board to LCD position. Also remember to remove the STEREO/MONO jumper as this is now controlled via MAX PRO exciter board menu system. APPENDIX G: DIP SWITCH FREQUENCY TABLE NOTE: If you want to use DIP switches instead of the LCD display module to set power, remove LCD display module and set DIP switch to a desired value. The only forbidden setting is all switches to off (this means you are going to use LCD module). If you want to use LCD control module, set all DIP switches to OFF!!

12 NOTE: THIS TABLE TO BE UPDATED SOON, IT IS NOW TAKEN FROM MAXPRO3+Below is a table for the dip switches, in importance they go from 12.8MHz (see the PCB) down to 100KHz (0.1MHz). For example, if you want a frequency of 86MHz look below and set all 8 switches to 0 (off), than look at the small table for a value of 0KHz and set the smallest of the 4 switches to 1. Done!

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