One of the first steps when building your own FM transmitter from modules will be the choice of exciter module. Below are a few typical scenarios. Consider reading this guide for setting up drive in cinema FM radio written by PCS Electronics. It contains interesting information to get started in other situations, too.
Typically scenarios in the field:
Small community stations in remote areas.
STMAX9015 or STMAX3015 micro work best for these since they have built-in stereo encoder and RDS. This reduces both cost and complexity. It can also be easily programmed via LCD to set the RDS parameters. Audio quality is pretty good. Spurious level is not suitable for professional setups as integrated digital modulator creates some in-band artefacts about -50dBc down. If you’re looking for a simple solution where those issues are not a factor (remote rural area) you will not be disappointed.
Small and large stations that require compliance with standards and high signal purity
MAXPRO8015+ works best. You will also need a separate SE8000 DSP+ stereo encoder for stereo. It is equipped with DIGIAMP interface. Very clean. They can drive any amplifier up to 10KW and more. Used in our high quality CE certified CyberMaxFM+ SE+ and BE+ series.
Stations that require absolutely best audio possible and excellent bass down to 1Hz.
The only solution here is DDS, it enables perfect Left/Right separation and best possible bass.
Here is a quick comparison chart between different types of our FM transmitters, click to enlarge:
Here is a quick comparison chart between different types of our FM exciters. Click to enlarge.
For all other considerations and questions, do not hesitate to contact us.
We have observed that many of our new inexperienced customers struggle with simple concepts and wiring 2-3 boards can sometimes be a problem. We have prepared a list of example packages which come with exciter, stereo encoder and sometimes also RDS and IO board. All these boards need to be wired together, installed into enclosure and connected to antenna and power supply to form a working transmitter. We strongly encourage you to install the boards in an enclosure, preferably metal enclosure with a small fan (40×40 should work). Running without a small fan or metal enclosure does not insure sufficient cooling and is not recommended.
We will list these example packages below with their main characteristics, you can read more about the used components in their respective listings (they are all available for purchase on this website). UPDATE: A new DDS MAX PRO exciter has been released, its performance exceeds the performance of MAXPRO8015. It also does not require separate RDS and Stereo encoder. The bass performance and stereo separation are better than those of MAXPRO8015.
Pro level 15W stereo FM transmitter with RDS and remote control via USB Contains:
–MAXPRO8015+ SuperBass FM exciter with LCD (2×16 + rotary encoder button)
– SE8000DSP+ stereo encoder – RDSMAX8000 mini RDS board
– IO board with 3 BNC inputs
– Pre-drilled LCD panel (rotary button 2×16) for easy assembly
– Pre-drilled back panel for SE8000 for easy assembly
– Pre-drilled back panel for IO board for easy assembly
Specifications:
– 15W, operates from 12-15V DC (2.5A)
– BNC antenna connector
– Excellent stereo sound
– Fantastic stereo separation
– DSP sound processor (adjustable pilot via LCD etc)
– RDS with PS, RT and all other functions
– Two RCA audio inputs
– Two XLR audio inputs
– Digital audio input
– USB –
BNC connectors for MPX in, MPX out and 19KHz pilot (TTL)
– Remote control with PC via USB or RS232 for full control over transmitter functions
Requires:
– Antenna and 15V mains power supply
– Enclosure
Pro level 25W stereo FM transmitter with RDS and remote control via USB Contains:
–MAXPRO8025+ SuperBass FM exciter with LCD (2×16 + rotary encoder button)
– SE8000DSP+ stereo encoder
– RDSMAX8000 mini RDS board
– IO board with 3 BNC inputs
– Pre-drilled LCD panel (rotary button 2×16) for easy assembly
– Pre-drilled back panel for SE8000 for easy assembly
– Pre-drilled back panel for IO board for easy assembly
Specifications:
– 25W, operates from 12-15V DC (4A)
– BNC antenna connector
– Excellent stereo sound
– Fantastic stereo separation
– DSP sound processor (adjustable pilot via LCD etc)
– RDS with PS, RT and all other functions
– Two RCA audio inputs
– Two XLR audio inputs
– Digital audio input
– USB
– BNC connectors for MPX in, MPX out and 19KHz pilot (TTL)
– Remote control with PC via USB or RS232 for full control over transmitter functions
Requires:
– Antenna and 15V mains power supply
– Enclosure
Pro level 400W stereo FM transmitter with RDS and remote control via USB Contains:
–MAXPRO8015+ SuperBass FM exciter with LCD (4×16 + rotary encoder button)
– SE8000DSP+ stereo encoder
– RDSMAX8000 mini RDS board
– IO board with 3 BNC inputs
– 400W AMPBOX with high-power fans
– DCDC to generate 15V for exciter
– Pre-drilled LCD panel (rotary button 4×16) for easy assembly
– Pre-drilled back panel for SE8000 for easy assembly
– Pre-drilled back panel for IO board for easy assembly
– 1800W mains power supply (220V required for full power)
Specifications:
– 400W, operates from 220-240V mains
– 7/16 antenna connector
– Excellent stereo sound
– Fantastic stereo separation
– DSP sound processor (adjustable pilot via LCD etc.)
– RDS with PS, RT and all other functions
– Two RCA audio inputs
– Two XLR audio inputs
– Digital audio input
– USB
– BNC connectors for MPX in, MPX out and 19KHz pilot (TTL)
– Remote control with PC via USB or RS232 for full control over transmitter functions
Requires:
– Antenna and mains power
– Enclosure, best put it in 2H rack,
– Mains cable and mains switch
–Maybe some normal strength size 80×80 fans
Pro level 1000W stereo FM transmitter with RDS and remote control via USB Contains:
–MAXPRO8015+ SuperBass FM exciter with OLED display with web control interface
– SE8000DSP+ stereo encoder
– RDSMAX8000 mini RDS board
– IO board with 3 BNC inputs
– 1000W AMPBOX with high-power fans
– DCDC to generate 15V for exciter
– 1800W mains power supply (220V required for full power)
– Pre-drilled LCD panel (rotary button 4×16) for easy assembly
– Pre-drilled back panel for SE8000 for easy assembly
– Pre-drilled back panel for IO board for easy assembly
Specifications:
– 1000W, operates from 220-240V mains
– Full remote control via WEB browser
– UECP compatible RDS
– 7/16 antenna connector
– Excellent stereo sound
– Fantastic stereo separation
– DSP sound processor (adjustable pilot via LCD etc.)
– RDS with PS, RT and all other functions
– Two RCA audio inputs
– Two XLR audio inputs
– Digital audio input
– USB
– BNC connectors for MPX in, MPX out and 19KHz pilot (TTL)
– Remote control with PC via USB or RS232 for full control over transmitter functions
Requires:
– Antenna and mains power
– Enclosure, best put it in 2H rack,
– Mains cable and mains switch
–Maybe some normal strength size 80×80 fans
Recommendations for assembly of transmitters:
1. Install the boards into metal enclosure, fan is recommended for exciter
2. If full power is too much, set power limit jumper to desired setting with jumpers (you can select 1W, 2W, 3W, 4W, 5W, 6W, 7W, 8W, 9W, 10W….or 15W)
3. Connect antenna, audio input and supply voltage
4. You can change power and frequency with LCD as desired 5. With mains operated units please beware of high voltage, it can be deadly. Use inline mains fuse and mains filter.
How does this work with driving amplifiers?
8015+ is easy to setup for driving a pallet amplifier:
– Set power limit jumper to desired drive power setting with jumpers (you can select 1W, 2W, 3W, 4W, 5W, 6W, 7W, 8W, 9W, 10W….or 15W)
– Connect the SWR and power reading voltage to PWR and SWR pins (2015) or just connect DIGIAMP cable to our filter (8015)
– Set the power meter voltage sensitivity (trimmers on directional coupler
– usually on filter) as you wish and the exciter will never drive your amp beyond preset value.
What is the Predrilled LCD front panel?
– This is a rectangular piece of aluminum with predrilled holes for LCD display, buttons and LED diodes. These exist also for stereo encoder and IO board. It also has 4 holes in the corner so you can easily mount this to your case. This makes it much easier to mount the transmitter into a nice looking case (eliminates the hard work with the LCD). This is of course an optional item.
To look for a suitable antenna check: here. To look for a suitable coaxial cable check: here.
Please ensure that you always run this or any other transmitter with antenna or dummy load attached.