Technical Manual

Technical Manual RF Mono
Cross Point Device Explorer v1.4 Page 36 of 47
View tuning 7.7.5.1.4
The Tuning scope view shows the tuning of the antenna. Each RFM antenna is factory
pre-tuned and should resemble an image as displayed below.
Figure 31: The tuning scope view
A properly tuned RFM antenna shows a more or less flat signal over the complete
bandwidth. Any visible peaks should preferably not be higher than the value 10.
In situations where the RFM antenna is installed close to (large) metal objects, like cash
desks, or if a metal shielding is placed behind the antenna, re-tuning of the antenna might
be necessary. Tuning of the antenna is done with the two variable capacitors C3 and C8,
which interact with each other. The object is to obtain an as flat as possible signal line
over the full bandwidth.
Do not change the tuning if you’re not sure what you’re doing, because a wrongly tuned
antenna will have reduced performance!
Reducing the detection bandwidth 7.7.5.1.5
In case of (high) noise in the lower frequencies, for example <7.7MHz, or in the higher
frequencies, for example >8.5MHz, the detection bandwidth of the receiver can be
reduced to eliminate the effect of this noise and to block detection for that area.
To reduce the bandwidth, just move your mouse cursor close to the left or right edge of
the detection band until you see the cursor change into a left-right arrow. Then click and
drag to move the edge of the detection band to the desired frequency.
The blocked area(s) are marked with a transparent light grey mask, under which the
signal line is still visible. In the blocked area(s) there will be no detection of any signals
(noise and tags)!
Figure 32: Reduced bandwidth example
Full bandwidth
Reduced bandwidth