Hallicrafters O-5B/FR exciter unit

[Opcom]

Does anyone have info or schematic on the O-5B/FR exciter? There is one here in VG cond. likely works. It looks like a 4-crystal oscillator with a switch, replaceable crystals are in a large front-opening oven. It seems that an external signal can be plugged into the back, not sure. It covers up to 6Mhz according to the controls.

CECOM shows only:
Exciter Unit   
1953-02-23
O-5C FR

xciter Unit O-5C/FR   1953-01-01   TM 11-2205A / TO 16-3505-6   Departments of the Army and Air Force
Exciter Unit O-5C/FR   1954-12-01   TM 11-2205B   Department of the Army
Exciter Unit, O-5B FR   1953-01-05   TM 11-2205A   Departments of the Army and the Air Force
Exciter Unit, O-5D FR, O-5C FR   1954-12-17   TM 11-2205B    Departments of the Army and the Air Force


Another search came back with the manual, specifically the "A" is required.
TM 11-2205A - -which is not in google, etc.

It could be used as a SBE with a DC-controlled +/-400Hz range. The control can come from an envelope follower, as the original use was as part of a fax transmitter where it too the envelope of the 1800Hz AM signal from the scanner and FM'd the oscillator with it. It served in place of a CW set's transmit crystal. Otherwise, it is a very stable VFO.

anyway still need the TM 11-2205A having the full details.