Radio Transmitter & Receiver Modules
T6 / R6
Application Circuit
The application circuits show how the QFMT6 transmitter and the QFMR6 receiver can easily be integrated
into a system to form a wireless link.
ANTENNA
ANTENNA
+5V
+5V
+5V
+5V
T5
1
2
3
4
5
1
1
2
3
4
5
6
7
8
9
A0
A1
A2
A3
A4
A5
A6
A7
VSS
HT12E
VDD
DOUT
OSC1
OSC2
TE\
AD11
AD10
AD9
AD8
18
17
16
15
14
13
12
11
10
R
OSC
A0
A1
A2
A3
A4
A5
A6
A7
VSS
HT12D
VDD
VT
OSC1
OSC2
DIN
D11
D10
D9
D8
18
17
16
15
14
13
12
11
10
DATA OUT 4
DATA OUT 3
DATA OUT 2
DATA OUT 1
R
OSC
1K5Ω
Ω
2
3
4
5
6
7
8
9
Quasar
R5
1 2
3 4 5 6 7
Figure 3: QFMT6 Quasar Transmitter Application Circuit
Figure 4: QFMR6 Quasar Receiver Application Circuit
RSSI Values:
The QFMR6 RSSI output provides a DC output proportional to the RF input signal. The table shows the
typical RSSI value depending on the RF signal strength
RF Signal Strength / dBm
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
RSSI / V
1.35
1.41
1.57
1.79
1.8
1.8
2.15
2.45
2.58
2.59
2.59
Typical RSSI Characteristics of the QFMR6
3.00
2.80
2.60
2.40
2.20
2.00
1.80
1.60
1.40
1.20
1.00
AGC
Action
RSSI (Volts)
-
120
-
110
-100
-90
-80
-70
-60
-50
-40
-30
-20
RF Signal strength / dBm
Note
that the region between –90 and –70 is with receiver AGC (automatic gain control) operating.
If required, a receiver version with AGC disabled can be provided as a factory pre-set option. This would
linearise the RSSI curve.
R. F. Solutions Ltd.,
Unit 21, Cliffe Industrial Estate,
Lewes, E Sussex, BN8 6JL, England
Tel +44 (0)1273 898 000
Fax +44 (0)1273 480 661
http://www.rfsolutions.co.uk
Email sales@rfsolutions.co.uk
R F Solutions is a member of the Low Power Radio Association.
Information contained in this document is believed to be accurate, however no representation or warranty is given and R.F. Solutions Ltd. assumes no liability with respect to the accuracy of such
information. Use of R.F.Solutions as critical components in life support systems is not authorised except with express written approval from R.F.Solutions Ltd.
DS306-3
May 03
2003
REG No 277 4001, England.
Page 7
RFSOLUTIONS [ RFSOLUTIONS.LTD ]
