JUMA
FM70 front view
Overview
JUMA FM70 is a compact digitally controlled FM transceiver for the 70 MHz amateur radio band
(4 m).
JUMA FM70 provides 15W RF output and the RX sensitivity is excellent.
The front-end is designed to withstand the near by high power FM broadcast stations
by high selectivity multi pole band-pass filter. Low noise Dual gate MOSFET
is used for high sensitivity. The narrow band selectivity is defined
by two IF frequencies, the first 10.7 MHz is using XTAL filter and the
second IF 455 kHz is using two cascaded ceramic filters.
Smart
construction
JUMA
FM70 smart contruction is based on one main board which inludes RX,
TX, PLL, and microcontroller. Rear panel inludes the connectors and
final RF MOSFET. Behind the front panel there is the control board which
includes the VOL pot, SQU pot, Power button, Mic connector, LCD display and the encoder with push button
for configuration.
JUMA FM70 internal view
Connectivity
- Mic connector with PTT in
- Power supply
- Antenna 50 ohms (BNC connector)
- Line in e.g. for PC sound card and line in PTT
- Line out, ext speaker or phones
- USB connector for software updates and control
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JUMA
FM70 rear view
Features
- RF output power 15 W (High) 1.5
W (Low)
- Supply voltage nominal
14 VDC (range 10 VDC...15 VDC)
- Typical current RX 100mA,
TX 2 A
- Frequency range 65 MHz...75
MHz
- Channel steps 10 kHz, 12.5
kHz, 25 kHz, 50 kHz
- Solid
state T/R switching
- Excellent RX sensitivity -125 dBm (125nV) SINAD 10db
- Squelch sensitivity typical better that 100 nV
- 1750
Hz tone encoder
- Small size Width 153 mm,
Height 50 mm, Depth
180 mm
Multifunction LCD
- S-meter bar indicator
- Output power, both bar and numerical
- SWR display
- Supply voltage indicator
- Frequency display
(6 digits e.g. 70.2625 kHz)
- State indicator (SQ, RX, TX)
Configurable features
- Channel
steps 10 kHz, 12.5 kHz, 25 kHz, 50 kHz
- LCD contrast
- LCD backlight
JUMA
FM70 internal details
Easy
building
- No coils need to be wound
- No wiring hassle
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70 MHz FM transceiver Last
update 2012-02-18
