Unable to get lock onto W3A

I've worked out the pointing angles for both sites:
Lusaka
Az=316 magnetic compass
El=59.6
Pol=-52.7 (this is nominal, W3a may be tilted a bit, say -56 deg)

Chama
Az=301 magnetic compass
El=57
Pol=-65.8  (this is nominal, W3a may be tilted a bit, say -69 deg)

So when you moved to Chama the polarisation needed turning a further -13 deg anticlockwise, while facing towards the satellite.

I'm guessing that the polarisation is the problem.

I would record now what is your polarisation angle.  Then make a deliberate error in the polarisation to see what error causes failure, as perhaps in Chama.

If there are equal power carriers on both polarisations (level 0 dB) then:

No polarisation error, wanted signal level = 0 dB
error of 10 deg will reduce the wanted signal by -0.1 dB
error of 20 deg will reduce the wanted signal by -0.5 dB
error of 30 deg will reduce the wanted signal by -1.2 dB
error of 40 deg will reduce the wanted signal by -2.3 dB
error of 45 deg will reduce the wanted signal by -3 dB

Note that misaligning the polarisation makes little difference to the wanted signal level.  Even a 45 deg error only reduces the wanted signal by -3 dB, about the same as a rain fade.

No polarisation error, cross pol interferer signal level = -30 dB
error of  5 deg will make the interference level -21 dB mild interference
error of 10 deg will make the interference level -15.2 dB noticable interference
error of 20 deg will make the interference level -9.3 dB  serious interference
error of 30 deg will make the interference level -6 dB very serious interference
error of 40 deg will make the interference level -3.8 dB impossible interference
error of 45 deg will make the interference level -3 dB wanted and interferer same level !!

Note that misaligning the polarisation very rapidly brings up the cross-pol interferer.

I would check where you are now, in Lusaka. Turn the polarisation until it fails.  Mark the angle. Turn back until it fails again on the opposite side and mark the angle.  Move to the exact centre. Is the angle = about -56 deg?   Try an inclinometer sideways across the BUC or LNB. Get your hub to do a CW transmit cross-pol test while you reach up under the feed arm and make microscopic polarisation turning movement.

Using Dish pointing Southern Africa


Lusaka


Chama

Best regards, Eric.