The ASTRO Saber, XTS3000 and ASTRO Spectra CPS and codeplug structure is VERY MUCH the same. You must correct any EOL (and EOB?) checksums after changing the status of this flag. In the MCS2000 codeplug, the ACK/ASK status is located at 0x37B. If the byte is E2, (1110, 0010), you would set it to 62.
So if you see 1000 (on, off, off, off), it's active. In binary, the status is represented by the first flag, in the first bit of the byte. In the MTS2000 codeplug, the ACK/ASK status is located at 0x28E. Obviously some of you are intelligent enough to be aware of how to get around this issue (force a new s-record in, or play with Lab), but for those who want to do things the hard/technical way, here's the information: This essentially means if you're ASK/ACK'd, your radio is a doorstop. When the ASK/ACK is enabled, one cannot write to the radio unless the ASK/ACK is connected to the programming computer. For those who like to play around, I have traced out the offsets and data for enabling/disabling the Advanced System Key (ASK) or Advanced Conventional Key (ACK) in the codeplug dataspace.