The classic novel of the Army Security Agency experience in Vietnam is James Crumley's One to Count Cadence. Old Spooks & Spies—the webHome of the ASA experience in Vietnman—keeps a list of recommended novels on ASA in Nam.
The shoulder patch for Military Assistance Command, Vietnam (MAC-V) has been modified to create a specifically ASA shoulder patch with a Radio Research tab. The sword of the MAC-V patch has been replaced by a lightning sword to symbolize ASA's SIGINT role. A lightning bolt is typically used in the insignia of ASA/INSCOM units. You can see this in the insignia for ASA (patch and DUI), Field Station Berlin, Field Station Rothwesten and INSCOM below:
Everybody "knows" that there was no ASA in Nam, but that doesn't mean that there is no ASA in Nam patch. The design below is a "Lightning Fast Chicken Plucker" patch camouflaged in the colors of the
Vietnam Service Medal.
design by T.H.E. Hill
The MAC-V Radio Research and camouflaged ASA designs pictured above are occasionally available on eBay as a 3.43" x 1.93" fridge magnets.
Voices Under Berlin is about the European ASA experience. You can learn more about it by visiting the links below. If you are looking for the Southeast Asian ASA experience, you can't go wrong with the Old Spooks and Spies webSite, where Voices Under Berlin is listed on their "Recommended Reading" page. Hill was awarded the coveted TANS “Recommended Reading” award for published authors in the 2012 Old Spooks and Spies Short-Story Contest for his story entitled “Lieutenant Bar.”