This is an S 308 Communications Shelter used by W8JBT/AAR9HH to support  emergency and field communications missions for US Army MARS and other agencies.  It is outfitted with a variety of data-communication systems and is in regular use on a number of MARS radio networks.

The left side of the S 308 shelter contains two vintage machines, a TT-76 teletype/ reperforator/transmitter in the foreground and a TT-4 teletype in the background. Both machines were manufactured by Kleinschmidt Labs.  Also present is a Yaesu FT-747 HF transceiver and ancillary decoding and support equipment.  All of the shelving and support structure internal to the shelter is made out of aluminum and constructed by W8JBT.     

The right side of the shelter contains the modern data communications system.  It consists of a laptop computer that provides all the encoding/decoding functions and a Yaesu FT-840 HF multi-mode HF transceiver driving a Heath HA-14 amplifier for a 500-watt PEP RF power output. The Vibroplex semi-automatic key supports manual radiotelegraph (CW) operation. 

Close-up of the RF shelf on the shelter right side: To the left is the FT-840 in a custom rack mounting, right is the Heath HA-14.  The wall-mounted unit is an ME-165 SWR/Wattmeter and dummy load.  The meter mounted below the shelf monitors primary voltage to the shelter, a necessity when operating from stand-alone power generators.

The primary transmitter for the indoor station of W8JBT/AAR9HH is an H-model BC-610, capable of 300 - 400watts of carrier output.   It is driven by a separate VFO, an Eico Model 722, to avoid the well-known problems encountered when using the internal VFO.

The receiver rack:  The top unit with the four meters is a Model CV-116 dual diversity combiner and decoder.  It operates on the IF signal from the R-390A immediately below it.  The receiver below the R-390A is an R-388 that is used primarily for AM 'phone operation.  The rack itself is vintage military surplus, is quite heavy and could possibly withstand nuclear-level shock and over-pressure.  To the right of the rack is yet another Kleinschmidt teletype.