The low-band MaraTrac radio was available with a 99-channel A7 Advanced Control Head HCN1090A that has a squelch adjustment knob. Unfortunately, the circuitry for this squelch control is not described in the MaraTrac low-band service manual 6880102W95. It is likely that Motorola published an FMR or SMR (yellow sheets) to cover this unique control head.
If any member of this list has the revision sheets covering the HCN1090A Control Head, please contact me off-list at mycall at verizon dot net. I would like to borrow those pages long enough to scan them for posting on the Repeater-Builder site. 73, Eric Lemmon WB6FLY
