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NOTE: This review mainly covers only the changes made to the updated Smart Booster (SB3a).  For a more thorough coverage of the Smart Booster features, please read the original Smart Booster (SB3) review.

New & Improved NCE Smart Booster (SB3a|SB5) - An Initial Review


A few weeks ago I sent in my old Smart Booster (plus a $60 check) into NCE to exchange it for the new and improved Smart Booster (SB3a), which I received in the mail July 12th, 2010.  Since I reviewed the original SB3 way back in Nov. ’06 and posted it on the forum, I thought I would do the same with the upgraded SB3a.


Package and contents


The box the SB3 came in was well packed and included the following:


  1. (1) Smart Booster (SB3a) – Software v.1.28D2

  2. (1) 4-socket Molex connector

  3. (1) SB3a manual containing the following sections:


  • Update information

  • Power supply requirements

  • Front & rear panel features (diagram) – Terminals, buses, status light, and ground screw

  • Diagram – Grounding the SB3a to other NCE DB3 (or dumb) boosters using the ground screw on back panel

  • Short Circuit protection (including #1156 bulb short detection diagram)

  • Diagram – Connecting the SB3a

  • Connecting extra boosters

  • Layout wiring

  • Electrical specifications

  • Available connections

  • Indicator light

  • DCC specifications of the SB3a

  • Resetting (rebooting) the system

  • Extended Function control

  • Using a Programming Track (including setup diagram)

  • Diagram – Advanced Layout wiring

  • SB3a Booster mode (or disabling the SB3a in order to use it in booster-only mode)

  • Power Cab and SB3a accessories


Items not included (and must be purchased separately):


  1. 5A power supply (NCE P515 pictured on right of SB3a)

  2. RJ12 cable - For making connection between SB3a and a UTP panel


Upgrade improvements from SB3 -> SB3a


The updated SB3a is housed in a new enclosure, with all connections now accessible from one side instead of two.  Connectors on the front panel are arranged in the following manner (from L -> R):


  • (1) 4-socket Molex connector – 2 slots for power; 2 slots for track bus

  • (1) Control bus port (RJ12) – Used to daisy-chaining additional "dead" boosters (e.g. NCE DB3a) to an SB3a

  • (1) Status LED – On when working properly; flashes when short detected

  • (2) Cab bus port (RJ12) – For connectiing the SB3a to UTP panels and/or additional throttles


Externally, the redesigned enclosure is very nice and the front panel is clear and understandable.  However, the one thing I would have done differently was to put all the connectors and connections on the backside of the unit rather than the front so that wires and cabling are more hidden from view.  I would have then left the red status LED on the front of the SB3a because that lets you know whether the units is functioning properly or whether it has detected a short.


Feature changes made to the SB3a:


  1. Redesigned enclosure – Maybe 10% bigger in size than the original SB3

  2. Recall stack* increased from 2 to 6 per cab – (See *NOTE: Recall stack default set at "2" below)

  3. Total amperage output ncreased from 3A to 5A

  4. Works with auto-reversers and circuit breakers

  5. The command station of the SB3a can be disabled in order for it to be used as a separate 5A power booster with another manufacturer's DCC system – Pg. 7 of the manual uses the term "dumb booster" when setting the SB3a to booster-only mode.  I'm assuming then that it functions just like a DB3a when hooked up to a PH Pro or to another SB3a.  I will get clarification on that.


Features unchanged between the SB3 and the SB3a:


Maximum number of cab address slots; total 4 – The Power Cab only has one additional cab address slot, for a total of 2


*NOTE: Recall stack default set at "2" – In order to increase the recall stack, you must specify the number of recall slots for your Power Cab or Pro Cab throttles using Programming Mode**.  To accomplish this task, follow the programming sequence below:


  1. Press PROG/ESC 5 times – LCD screen will display "SET CAB PARAM[eter]S"

  2. Press ENTER – LCD screen will display the number of recall slots programmed into your throttle (Default: 2)

  3. Press 3, 4, 5, or 6 to change the recall slot number to a value other than "2"

  4. Press ENTER

  5. Press PROG/ESC to exit Programming Mode


**NOTE: Programming mode - Because the SB3a does not come with a programming track output, you will still need your Power Cab and PCP panel for programming in Programming mode




  • SB3a (w/trade-in/upgrade) – $60, plus your old SB3 is mailed to NCE

  • SB3a (w/o trade-in/upgrade) – $159.95 MSRP; $124.76 – $127.96 (discounted)


Additional comments


Although I haven’t had much of a chance to take my SB3a through its paces, apart from my earlier comments on (and preference of) the Control bus and Cab bus connector locations, I’ve liked what I've seen so far with the redesign.  I think the improvements make sense and, as I have mentioned in other threads, NCE has wisely taken a page out of Digitrax’s design book and made the new SB3 a non-dead end system this time. (A glaring shortcoming of the original SB3.)


Should you decide at some point to upgrade your Power Cab and SB3a combo to a Power Pro (PH-Pro) or PH-Pro R "wireless" DCC system, the Power Cab will continue to function as a ProCab throttle and the SB3a booster can be integrated into your layout as an additional power booster.


Also, although not mentioned outright, the diagram on pg. 3 of the Smart Booster manual seems to indicate that an NCE RB02 Radio Base station can be hooked up to an SB3a so that radio throttles can be added.  (I believe this was also capable on the original SB3.)


Anyhow, as usual, I hope this review serves as an aid to others who either want to know more about the new SB3a, or who may be contemplating whether the SB3a (or upgrade from their SB3) is right for them and/or worth the added expense.  I also hope to make further comments to this thread as I have additional opportunity to utilize my SB3 on my layout.

Initial overall rating and satisfaction: A-


UPDATE - In 2013, I sent $20 to NCE for an new eprom so that I could upgrade the firmware in my Power Cab from V1.28D to V1.65.  After installing the new eprom, the Power Cab began acting strangely; exhibiting weird anomolies on the LCD screen when I tried to operate a locomotive.


Long story short, after a couple of replacement eproms didn't remedy the issue, it was discovered that the upgrade V1.65 eproms didn't get along with the SB3a eproms.  Larry mailed me a SB5 eprom (which has the same hardware as my SB3a) and that solved the anomoly issues.


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