[time-nuts] Trimble Resolution-T versus Resolution SMT

[Mark Sims]

I got in a couple of Resolution-T receivers from fluke.l and have had a chance to compare them with the Resolution SMT:

The -SMT receivers appear to be new.   Mine were the TEP variant (Motorola compatible) that has to be reconfigured to be TSIP compatible.   The -T receivers are used.  Mine came with locations in rural China stored in their survey position.  The -T serial port comes set for 9600,8,Odd,1  (Tbolts are 9600,8,N,1)

The receivers are physically and electrically compatible.   They are mostly software compatible.  The -SMT only works at fixed locations.  The -T can work in mobile applications or as a general purpose GPS receiver.

The -T is a 12 channel receiver and the -SMT is 14 channel.   The -SMT is 6-8 dB more sensitive.  The -SMT tracks and reports info on all sats that it sees (even if below the elevation and signal level masks).  The -T only tracks and reports info on the sats above the masks.

The -T has a +/-20 ns PPS,  the -SMT has a +/- 14 ns PPS.  Both support external sawtooth correction.

The -T responds to the dynamics filter (0x70) message.  You can enable the PV, Static,  Altitude, and Kalman filters  (Kalman overrides the others).

The -SMT serial port occasionally glitches messages.

The -T receiver shuts down for a couple of seconds when writing parameters into its EEPROM.