Special Considerations in Z Scale

Voltage is the prime concern, you need to keep the voltage down to avoid melting motors and sometimes lamps. If your supply cannot be turned down enough, make one or more full wave bridges using "fast recovery" diodes and put in series with the power to the track. The fast diodes will keep from messing up the DCC signal (rounding off the "corners").Here's an exampleFR601DICT-ND from Digikey 

Some Z is fine on 8 volts, some 10. Many systems will only go down to 12v. ***need*** to determine which locos and best voltage

Decoders for Z scale

There are some "drop in" decoders for Micro-Trains locos.

TCS - Train Control Systems

TCS makes the MZA4. There was a "recall" where there was copper very close to where the motor springs go. This copper was connected to the circular "land" that the chassis "pins" connect to, thus creating a short between the motor and the track pickups. Don't know the dates on this. http://www.tcsdcc.com/Customer_Content/Technical_Info/Tech_Info/FAQPage.php?q=64

The solution is to cut/grind away the little chunk of copper in the picture (or you could use kapton tape it seems)

The manual given sucks in my "DCC" opinion. I'm going to add in the CV's here, because some are not listed, and many are listed in a confusing way. 

CV 1, 2, 3, 4, 5 17, 18, 19, 23, 24 all standard, note cv6 mid speed is available, nice

CV 8 is decoder reset, set to 2 for reset, resets most stuff. Read back for manufacturer id, should be 153 for TCS

Factory reset can be done on the main track or on the programming track. To reset CV's to there factory setting write a value of 2 into CV8. The reset occurs the moment the decoder gets the reset command. (Earlier decoder versions had to go through a power on/off before the reset occurred.) CV's that will reset to factory default: 1, 2, 3, 4, 5, 6, 17, 18, 19, 29, 30, 49, 50, 53, 54, 55, 56, 57, 61 . The user-loadable speed table is not affected by the reset

CV 15 is decoder lock, to unlock set to zero or equal to CV16, setting CV 15 to 7 locks all decoders that are at same address (I guess this implies POM)

CV 16 works with CV 15, convention is to set to a number for groups, can be set to anything apparently, see the manual for a confusing explanation, but =1 for mobile, =2 for sound, =3 lights only as defaults, you can set it to anything if you want a unique lock.

 

CV29 - follows standard

0 (1) - reverse direction

1 (2) - enable 14 speed steps(default !!!)

2 (4) - disable DC mode (default !!!)

4 (16) - activate loadable speed table

5 (32) - enable long address

 Note that 14 speed steps and no DC mode seem to be default... weird.

CV 56, 57, "dither" frequency and voltage - when enabled, it is enabled all the time.

Like "kick start" in NCE, only works if BEMF is off. Both need to be greater than 0 to be working.

56 is frequency, default is 3, 1 is highest freq, 255 is lowest

57 is voltage, default it 10, lowest is 1, highest 255.  tcs recommends using 25 as a starting point and moving up or down 5 at a time to see when it improves.

CV 61 - BEMF control and dimmed lighting

•  Set to 0 turns BEMF off
• bit 0 (1) - enable BEMF
• bit 1 (2) - enable function button control of BEMF (won't come on unless bit 0 is 1) (default is function key 6)
• bit 4   (16) - enables dim when stopped
• bit 5 (32) - enables the "opposite" light dimmed (rear light dimmed in forward)

CV 64 - sets dimmed brightness

2-6 for LEDs, 12-18 for bulbs. Wonder what the limits are

CV  10 sets BEMF cutout speed

defaults to 0, i.e. BEMF always on... range is almost exactly mapped to speed steps, so if you want it to cut out at ss 10, set to 10. This might be helpful in consists.

CV 13 - analog power control "turn off black or red powered functions"

 analog power conversion (DC mode) must be enabled in CV29... I cannot figure out what the heck this does, it also refers to "brake on DC", looks like it will stop the loco (subject to CV4 setting) when DC is applied

CV 18 - consist lighting controls

refers to setting to 3 for white and yellow wire... my guess is that you can set it up to disable headlight and/or backup light when in consist

CV 136 will let you remap what function button turns BEMF on or off. 

My experience has been that these sometimes do not respond to the reset command. I go through other registers and "zero" them out, and this has solved problems several time.

 CV 49-52 control the lighting effects for the outputs for white, yellow, green, purple. (white and yellow are front and rear lights)

 set to 0 through 13 for front light only, add 16 for reverse light only , add 32 for both

 

CV249 - read TCS model number.

• MZA4 is 40
• Z2 is 41
• FL2 is 6
• FL4 is 7

Digitrax

MTL GP35 - Digitrax "drop in". Watch for the engine springs flying away.

Installing in a MT F7

Link to Glen Chenier's article on the wiring for DCC web site:  http://www.wiringfordcc.com/zmtf7.htm anyone with an F7 should read this because it starts out with Glen's outstanding tips on overhauling / tuning the mechanicals of the loco.

Lindley Ruddick 

Glen comments on this:

A more recent version with better chassis cut description and better decoder test procedure is on the yahoo z_scale list under Files > DCC.  This is still outdated, the newer DZ143 pcb layout and DZ125 require the right chassis cutting to slope deeper downward around the worm cavity to clear the tallest component.  Will have to look into the TCS Z2.  Anything that raises the shell even slightly can cause the front coupler housing to touch the edge of the shell opening.

A gotcha is if one cuts too deep into the bellgear cavity the wires will rub on the exposed bellgear.

Another way to isolate the motor terminals from the chassis is to leave them uncut but slip a rectangle of overhead projector transparency film between the chassis and terminals AFTER soldering.  Does the same thing, but now the motor terminals remain intact in case you ever want to go back to the original.

Some notes from Lindley Ruddick on his installation:

Isolation of the motor from the frame is no big deal when you trim the brush tabs. I used a jeweler's saw/razor saw/Zona saw to notch the frame on the end away from the cab and did the finish work with a file.

I used a Digitrax DZ123/125 as that is what I had and that is what Glen used. If I were to do it again, I would seriously look at the TCS Z2 which was not available when I did mine.
I have done 2 with no problems and plan to do a third. I would say it took me 3 hours to do the work (including bathroom breaks, coffee breaks and TV breaks). Certainly achivable in one evening or afternoon.

My MTL F7's all run better in one direction than the other so I attempted to orient the frame to run forward in the leading unit and backwards in the trailing unit. If you are not careful when you solder the wires to the brushes and reinstall the motor you might end up with "reversed" rotations. I am pretty sure you can "cure" this by changing the CV's for "forward direction" and lighing effects.

Z scale DCC notes from Jeff Merrill

You can improve the speed in the SD70's. One issue will all the locos, from MTL's early F7s to the GP and AZL's SD's: the two halve of the motor house exert pressure on the internal parts causing slight binding. As anyone that has had an MTL F7 knows, simply loosening the screws on the motor housing (every so little) can make a big difference. Same with the GPs and somewhat with the SD's. There are some other issues with the AZL SD's that Robert Ray discovered. They drive the axle worm gear thru a flexible plastic tube. This is not always perfectly 'slid' on the motor shaft or worm gear, creating a sort of binding. More significant it seams is the worm gear bushings are swivelling balls with thru holes. These are held in place by a black plastic block. The block has a tapered shape and fits tight into the motor halves. It appears that this compresses enough to hold the brass bushing too tight so it does not freely move with the gear flexing. I have filed mine down (removed the taper) so that it fits more freely in the motor halves. I got about a 30% speed improvement with a bit less current demand. Rob got at least a 50% improvement, at least as fast as the GP.

Of course, with any loco, there are a lot of gears so make sure they
run freely too. Check the lubrication (thin, viscous, plastic
compatible oil like Labelle 108) and frequently clean and relube,
not just relube as it will get gummy over time, especially the motor
bearings in a Marklin engine (NOT a GP or SD !)

What's available in decoders:

CT Elecktronics (smallest), Uhlenbrock
73400 (middle size) or Lenz Gold Mini (largest of the 3). 

DCC Manufacturer ID table:

• 001 CML Electronics Limited UK
• 002 Train Technology
• 011 NCE Corporation (formerly North Coast Engineering) US
• 012 Wangrow Electronics US
• 013 Public Domain & Do-It-Yourself Decoders
• 014 PSI – Dynatrol US
• 015 Ramfixx Technologies (Wangrow) CA/US
• 017 Advanced IC Engineering, Inc.
• 018 JMRI
• 019 AMW
• 062 Tams Elektronik GmbH
• 066 Railnet Solutions, LLC
• 068 MAWE Elektronik
• 071 New York Byano Limited
• 073 The Electric Railroad Company
• 085 Uhlenbrock GmbH DE
• 087 RR-CirKits
• 095 Sanda Kan Industrial (1981) Ltd.
• 097 Doehler & Haas DE
• 099 Lenz Elektronik GmbH DE
• 101 Bachmann Industries US
• 103 Nagasue System Design Office JP
• 105 Computer Dialysis France FR
• 109 Viessmann Modellspielwaren GmbH DE
• 111 Haber & Koenig Electronics GmbH (HKE) AT
• 113 QS Industries (QSI) US
• 115 Dietz Modellbahntechnik DE
• 117 cT Elektronik AT
• 119 W. S. Ataras Engineering US
• 121 ECCO GmbH (Tentative)
• 123 Massoth Elektronik, GmbH DE
• 125 ProfiLok Modellbahntechnik GmbH DE
• 127 Atlas Model Railroad Products US
• 129 Digitrax US
• 131 TRIX Modelleisenbahn DE
• 132 ZTC UK
• 133 Intelligent Command Control US
• 135 CVP Products US
• 137 A-Train Electronics US
• 139 RealRail Effects US
• 141 Throttle-Up (Soundtrax) US
• 143 Model Rectifier Corp. US
• 145 Zimo Elektronik AT
• 147 Umelec Ing. Buero CH
• 149 Rock Junction Controls US
• 151 Electronic Solutions Ulm GmbH DE
• 153 Train Control Systems US
• 155 Gebr. Fleischmann GmbH & Co. DE
• 157 Kuehen Ing. DE
• 159 LGB (Ernst Paul Lehmann Patentwerk) DE
• 161 ROCO Modellspielwaren AT
• 163 WP Railshops CA
• 165 Model Electronic Railway Group
• 170 AuroTrains US/IT
• 173 Arnold – Rivarossi DE
• 186 Brawa Modellspielwaren GmbH DE
• 204 Con-com CH
• 238 NMRA reserved