[Milsurplus] AN/TNH-21 tape deck manual needed - NSA?

[Nick England]

I've just acquired a nifty AN/TNH-21 tape deck (4 channels, 5 speed)
that was used by the Navy and others for signal intercept and
analysis.
Photos at http://www.navy-radio.com/record.htm

But I need a manual as the capstan servo is running open loop and it
sounds like an F-104 spooling up for takeoff.
I have found this reference to a manual -
"AN/TNH-21 Recorder-Reproducer Set, Sound, Instruction Manual,
National Security Agency, Fort G.Meade, MD, December 1973."

and a NSA video tape catalog lists
"AN/TNH-21 RECORDER (U) TVC-608 1974
Running Time: 357:56 Classification: Unclassified 9 Parts
(U) A nine-part maintenance series on the TNH-21 including:
introduction; system specifications;
capstan servo system; phase comparator; system power supply; circuit
analysis; drive
circuitry; and counter reset. (Black and White)"

So, any suggestions on how to get hold of an NSA manual or video?

cheers,
Nick
www.navy-radio.com