Setting up the Spectrum Mode ( ingress test ) involves changing a few parameters that should be familiar if you have ever set up the Acterna 1450/1750 for the Ingress Test.
From the NAVIGATION MENU arrow to option “3”, SPECTRUM.
The very first parameter will be highlighted- “ref” Change this to “0” using the ARROW DOWN key.
-Arrow to Avg, Arrow up to “16”
-Arrow to Lim, Arrow down to “-25”
-Arrow to Db/div and Arrow up to “10”
-Arrow once right-
You have now set the display and limits so they more closely resemble the 1450/1750 Ingress test screen. Your top row should appear as below-
Ref= 0 Avg 16 RBW 300kHz Lim= -25 10dB/div
Set START AND STOP freqs.
You should now have “Start” highlighted. If it states “Center” instead of “Start”, press the yellow softkey under TUNING and select #2 for “START AND STOP”
Press ENT and input “5”, press ENT ( to set START freq )
-Arrow right, Press ENT and input “760”,( or 860 depending on plant) Press ENT ( to set STOP freq )( see edit below for reasons)
You’ve just set your start and stop frequency.
-Now arrow right again and you will be on MARKER A.
Input “5”, press ENT
-Arrow right once and you will highlight MARKER B.
Input “42”, press ENT
Set MARKERS
You will notice the left hand side of your ingress graph will have a vertical line. Your Markers A and B are Vertical Lines used to pinpoint frequencies on your graph. You can change them as you need them when trying to pin point an exact freq on the graph. They are currently set up now to isolate the return path freqs from the forward freqs. The return path freqs being everything left of the vertical line.
If you are still connected to active plant remove the jumper from plant to view an accurate ingress test to ensure the settings suit what you are used to. Touch your jumpers Center Conductor to something metallic to cause ingress to again ensure all settings are working as you would like.
EDIT-
** In my experience for a service tech doing a full spectrum ingress scan will yeild more useful info then an isolated 5-42 reverse ingress scan. With UHF and VHF bleeding into lines it doesnt make sense to limit your visibility to only the reverse. Reverse ingress issues are in the minority when it comes to premise issues. If your area determins 5-42 with no deviation I would recommend trying it yourself with a full spectrum to see if it helps you out more.
For Maintenance youll obviously be more concerned with reverse ingress knocking out your node. But due to forward sweep capabilities, more maintenance depts are using the DSAM and service the 860DSP.
