Paradise P300 Test Menu, Test 1Loopbacks Off 2RF & FEC Off PSU/Temp 4Int Bert ESC, Fec L

Normal operation is selected.

Test, Loopbacks Menu

6.16TEST MENU

The test menu is as shown below, and leads on to the menu’s described in the following few paragraphs. When either a loopback or test mode are active, the TEST LED on the front of the equipment illuminates.

Test: 1:Loopbacks [Off] 2:RF & FEC [Off]

3: PSU/Temp 4:Int BERT [ESC]

Test Menu

Each of these options is now discussed in turn:

6.16.1 Test, LOOPBACKS Menu

Loop (now Intfc): 1 Off, 2 Interface (L+R),

3 FEC (L), 4 I.F. (L) ( More)

This screen show the most common loopbacks, but by pressing9the down arrow further options are provided. The loopback options are:

OFF

INTERFACE (L+R) An interface loop (Local and Remote) is selected, providing both a terrestrial loop and a loop to the data from the remote end of the satellite link. The exact implementation of the loop is interface dependent. On G.703 cards it is a `copper loop`, on other cards the loopback is provided by a multiplexer at TTL levels. If an INTERFACE LOOP doesn’t make the sync light on the firebird come on, your looking in the wrong place, its not the modem, try the cables !

For the remote loopback to function when this loopback is selected the clocking must be configured in a mode where it would work if the loop were made in the cables. Rx clocking must be set to something other than Tx Clock (switch to Satellite if this is the normal setting) and the Tx clocking must the set to Tx Clock In.

FEC (L)	The data is looped back after the FEC just before it enters the modulator
	providing a local loop only. The Tx data continues to be transmitted, and the Rx
	data from the satellite is ignored. ESC & Aux channel data (which is present in the
	data stream at the FEC) is also looped.
I.F. (L)	The Tx IF signal is looped back within the modem a IF. Tx data is transmitted as
	normal, and the Rx RF signal is ignored. The Rx IF Frequency is automatically
	adjusted to match the Tx IF Frequency (so the loop will function). ESC & Aux
	channel data (which is present in the data stream at the IF port) is also looped.
	When the loopback is switched off the RX IF Frequency is restored.
	NOTE: The Tx IF Level needs to be set to above -10dBm for the loopback to
	function reliably. Do NOT change the Tx IF Level for a loopback if the
	modem is still on satellite !
Cont’d....

P300H P300 Series Modem Installation and Operating Handbook Page 122