FM transmitter kits

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 that will help you decide.

Small community stations in remote areas, far from urban centers
STMAX3015+ works best for these since it comes with built-in stereo encoder and RDS. This reduces both cost and complexity. It can also be easily programmed via LCD without the need for PC to set the RDS parameters. You can mount one of these on the top of these amplifier modules, this will form a complete Stereo RDS FM transmitter. Audio quality is pretty good. Spurious level is not suitable for professional setups as DDS 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) do get one of these, you will not be disappointed.

Small community stations that require spurious levels to be >65dBc
If your signal needs to be clean but 15W is all you need, MAXPRO2015+ works best. You will also need a separate stereo encoder or audio processor with MPX output. The added benefit is that you can now also use MPX STL wireless link. MAXPRO2015+ can be used as a simple pallet amplifier driver.

Large stations that require spurious levels to be >65dBc
MAXPRO8015+ works best. You will also need a separate stereo encoder or audio processor with MPX output. You can also use MPX STL wireless link. It is equipped with DIGIAMP I interface and also supports MAXLINK II so when interfacing with SE8000 you don’t need to solder at all. Any of these can drive any amplifier up to 10KW and more.

Here is a quick comparison chart between different types of our FM exciters:

Name	STR-1000	STMAX3000+ series	MAXPRO2015+	MAXPRO7015+ series	MAXPRO8015+ SB	MAXPRO8015+ STR
Available today	Available in June 2020	Yes	Yes	Yes	Yes	Yes
Frequency range	87,5-108 MHz (76-90MHz on request)	87,5-108 MHz (76-90MHz on request)	87,5-108 MHz (54-68 and 76-90MHz on request)	87,5-108 MHz (54-68 and 76-90MHz on request)	87,5-108 MHz (54-68 and 76-90MHz on request)	87,5-108 MHz (54-68 and 76-90MHz on request)
Output power	100mW	15W/25W/35W/50W/100W	15W	15W	15W, 25W	15W, 25W, 50W, 100W
Supply voltage	12-15V	12-15V (48V for 100W)	12-15V	12-15V	12-15V	12-15V
PLL step size	100 kHz (down to 1KHz on request)	100 kHz (down to 1KHz on request)	100 kHz (down to 50KHz on request)	100 kHz (down to 50KHz on request)	100 kHz (50KHz possible)	100 kHz (50KHz possible)
Antenna connector	BNC	BNC	BNC	BNC	BNC	MXC or SMA
Modulation type	On-board 2xRCA, 2x XLR, USB and AES/EBU	L/R input (2xRCA), with new ucoming input board also XLR, USB and AES/EBU	Standard MPX input	Standard MPX input	Standard MPX	Standard MPX, RCA, XLR inputs
VCO type	DDS digital	DDS digital	Standard VCO + PLL	Standard VCO + PLL	Low noise VCO + PLL	Low noise VCO + PLL
Spurious output	~-50dBc	~-50dBc	<-65dBc	<-75dBc	<-83dBc	<-85dBc
Built-in stereo encoder	Yes	Yes	No, requires SE2000, SE5000 or SE8000 (SE7000 not supported)	No, requires SE2000, SE5000, SE7000 or SE8000. SE8000 DSP+ recommended!	No, requires SE2000, SE5000, SE8000 DSP+ recommended!	Yes, high quality DSP
MAXLINK support	Yes	Yes	Yes, MAXLINKI	Yes, MAXLINKI	Yes, MAXLINKII	Not needed
Built-in RDS	Yes	Yes	No, requires external	No, requires external	Same as 8015+	Plug-in available
What kind of STL link can be used	Split audio channels only	Split audio channels only	MPX or regular split audio channels (with stereo encoder)	MPX or regular split audio channels (with stereo encoder)	MPX or regular split audio channels (with stereo encoder)	MPX or regular split audio channels
Digiamp support	No	Yes	No, but it has input for external power and swr	Yes	Yes	Yes
RDS control	Directly from LCD display or via PC application	Directly from LCD display or via PC application	Via PC aplication, requires RDS encoder	Via PC aplication, requires RDS encoder	Via PC aplication, requires RDS encoder	Via PC aplication, requires RDS encoder
PC remote control	CyberNanoFM+ program	CyberNanoFM+ program	CyberMaxFM+ program	CyberMaxFM+ program	CyberMaxFM+ program	CyberMaxFM+ V60 program (more advanced than 8015SB)
Support for new large 4×16 LCD	Yes	Yes	No	Yes	Yes	Yes, new type with 16-lead cable
Super Bass:	Yes	Yes	No	No	Yes	Yes
Suitable for:	Low cost Stereo + RDS solution, all functions including RDS adjustable from LCD display. For remote areas.	Low cost Stereo + RDS solution, all functions including RDS adjustable from LCD display. For remote areas.	Low cost solution with a clean signal	Very clean signal for pro solutions, requires Stereo/RDS encoder	Very clean signal for pro solutions, requires Stereo/RDS encoder	Very clean signal for pro solutions, very practical all on single board