All my comments only apply to the microHD since I've never seen the 1200. You say both receivers are using the "same dish". Are both dishes connected at the same time? Using a diseqc switch? How is one dish connected to two receivers?
As configured, the correct default single satellite scan range is 10700 to 12200 MHz. You can edit that range, if you wish, by cursoring up and entering different frequencies using the keypad.
You mention you have a diseqc switch inline. On the microHD, do you have the DiSEqC 1.0 setting configured for the correct port of the diseqc switch (Port 1, 2, 3, or 4) to which the LNB is connected? This setting defaults to Disable. The notice of No Channel only indicates you haven't yet scanned in any channels. So that is a correct message until you have scanned in your first channel.
On the microHD, do you have the power to the LNB activated (System Setup>Other>LNB Power On)? Even if you can't scan in any channels for some reason, on the microHD you should still be able to see an RF signal for a given transponder frequency in the Installation>TP List screen if a signal is being received. If you cursor to a frequency listed in that screen, if the LNB is receiving a signal, then there will be a Signal Level and Signal Quality indication. If no frequency is in that screen, then you can manually add one using the Green Add button.