10W AM transmitter, now with DSP audio processor
There's been a void in the LPAM
market for a long time.... a big lack of an affordable, high audio quality
and reasonably powerfull AM transmitter. That's why we sat down and designed
AM MAX I. After evaluating the AM MAX I for a while we came up with a
new design, this time based on DSP. This makes it possible to control
parameters of the audio chain, such as the compression, low pass audio
filter cut frequency and preemphasis via convenient menu system (control
unit now comes with LCD display). Other features, such as the fully solidstate
PWM modulator which ensures absolutely crisp modulation, heatsink that
bolts to the enlosure for perfect cooling and LCD display unit make AM
MAX II DSP really shine. Due to innovative PLL design this unit offers
incredible low phase noise and is covering extremely wide frequency range.
PLL steps are 1KHz just because nobody asked for less. Hardware supports much smaller
steps. Units come with schematic diagram which shows the crucial details
of the transmitter, making it possible to use the PWM and PLL in another
design with higher output power. You can make use of the relay switch
logic as well. Fuse and main on/off switch are now right on the PCB. Perfect
for system integrators. Everything else can be controlled via display
unit and the UP, DOWN and MENU keys. OEM version available on request.
AM MAX II DSP comes in two versions, one for the broadcast band and one for
the HAM bands. Broadcast version is available right now. HAM version should
be available in about one month. PLL supports up to about 30MHz.
19" rack enclosure units are available. These enclosures have enough space inside for two
extra PCB's (holes are predrilled for them) and two extra apertures at
the back for an optional Canon connector and SO239 connector. This gives
you plenty flexibility and makes it easy to implement modifications/extensions.
- RF Output Power AM: 4-15W carrier (13.8-22V DC stabilised)
- Peak RF Output Power: 16-60W
- Output connector: BNC or SO-239 (on request)
- Output Impedance: 50 Ohms
- Frequency Range (MW version): 540-1710KHz (ask for other - 5000KHz-6000KHz etc)
- Frequency Range (HAM version): 160m, 80m, 40m (see price list below)
- PLL Steps: 1KHz
- Frequency stability: +/- 50Hz (trimmer on the PCB for fine tuning)
- Spurious/Harmonic rejection: Harmonics: -50dB, Spurious: -80dB
- Power Supply: 13.8-22V/4A DC stabilised
- Quartz Locked PLL Frequency Control, extremely low phase noise due to special design
- Ultra Stable, Ultra Clean Output
- Wideband design, no tuning required
- Audio performance: compressor, low pass filter, limiter, treble, bass adjustment
- RF output ruggedness: > 2:1 VSWR
- Modulation: AM (CW is possible with a small mod).
- PCB size: 170x125mm (LxW)
Suitable DIY antennas for
the AM transmitters:
link 3, link
AM transmitters in our forum!