Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

tsunumi 750 decoders

4963 views
18 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    January 2004
  • 166 posts
tsunumi 750 decoders
Posted by mmartian22 on Wednesday, September 9, 2009 7:05 PM

does   anyone know what causes inttermitted stop and starting  they are installed in b manns shay s and riverossi heisler, the track is clean .I have other units that run fine on this track I put them on the mainline and still stop and start checked all connections which is hard wired to the decoder s ,the wheels are clean.

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Wednesday, September 9, 2009 8:14 PM

 I use these decoders.

Are the loco wheels clean? How are the pickups at the wheels? How many wheels pickup? Are the pickups hard wired to the decoder? I have not seen the pickups on theses locos.

Do you have the stay alive capacitor in place? The instructions mention the stay alive capacitor.

Stay alive info link below. Store the link in the Favorites folder. This has been discussed ad nauseum in the Yahoo SoundTraxx DCC forum.

http://www.members.optusnet.com.au/mainnorth/alive.htm

Rich

 

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    January 2004
  • 166 posts
Posted by mmartian22 on Thursday, September 10, 2009 6:48 PM

the cap is connected to yell-grn and blue wires as per instructions  i called sound traxx they said to replace the pick-ups with a phosfer  - copper material   which improves  track -up b mann has a poor pickup system for these models . 

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Thursday, September 10, 2009 7:43 PM

davidmbedard

How where the installs done?  I have done many of these for my customers with narry an issue.

Are you sure the caps were not installed backwards?  

David B

Electrolytic capacitors do not like reverse voltage. Think large current flow, maybe decoder smoke. Very hard on the full wave bridge rectifier that track current passes though before reaching the delicate electronics. One person on another dcc group installed the cap reversed and smoked the decoder, plus the capacitor innards where inside the tender. Yes, I know some people do not believe that can happen.

Rich


If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Thursday, September 10, 2009 7:46 PM

mmartian22

the cap is connected to yell-grn and blue wires as per instructions  i called sound traxx they said to replace the pick-ups with a phosfer  - copper material   which improves  track -up b mann has a poor pickup system for these models . 

 

That sounds like a good suggestion but I would still go with all tender wheel pickup as I did with my Spectrums. My Roundhouse all come factory equipped with all tender wheel pickup.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    January 2004
  • 166 posts
Posted by mmartian22 on Sunday, September 13, 2009 5:26 PM

dave the rf caps are not cut all i was told by b mann was to just plug  it in  or hard wire in  .on the light board where are those caps on the board?

  • Member since
    January 2004
  • 166 posts
Posted by mmartian22 on Sunday, September 13, 2009 6:12 PM

rechecked wires to cap s this is what i got for  the 750 yell-grn is neg , blue is plus

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Sunday, September 13, 2009 6:43 PM

mmartian22

dave the rf caps are not cut all i was told by b mann was to just plug  it in  or hard wire in  .on the light board where are those caps on the board?

Hope this helps.

http://www.gatewaynmra.org/dcc/engines/bach-shay.htm

Rich

 


If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    January 2004
  • 166 posts
Posted by mmartian22 on Sunday, September 13, 2009 7:12 PM

the shay works thank you  now the climax which has two caps in it cut both or one ,but which  one if cutting one this one is supposed to be dcc ready it has leds  lites . that website is great

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Sunday, September 13, 2009 7:50 PM

Some Bachmann PC boards have two capacitors, usually labeled C1 & C2 right next to each other. Some PC boards only have C1. Cut both. For info, a label of R1 means a resistor. L1 means and inductor. Standard PC board labeling.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    January 2004
  • 166 posts
Posted by mmartian22 on Sunday, September 13, 2009 9:01 PM

thanks rich i will cut them off tomorrow and see what happens  my riverossi seems be a contact problem i think

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Monday, September 14, 2009 10:51 PM

Here is a photo of a PC board in the Spectrum 4-6-0 that was DCC Ready. You can see the DC adapter, tiny Surface mount resistors, Surface mount diode, leaded capacitors next to two leaded molded inductors. There are two Surface mount diodes under the board are hidden. I cut the capacitor after the photo.

If you look close, you can see three resistors and a diode for the LED headlight. Some boards have two resistors and a diode.

Why Bachmann has a capacitor for the LED, I have no idea.

I see wire wound inductors with no coating for your PC board. I have those in a Spectrum 44 ton diesel.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    January 2004
  • 166 posts
Posted by mmartian22 on Tuesday, September 15, 2009 6:14 PM

the climax appears to have the same board  i cut both cap s off  and it still starts and stop  .but not as bad , also going to add pick up strips to the tender in hopes this will work.. the heisler  i haven't got it. but thinking about pulling thr board out and hard wiring it

 

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Tuesday, September 15, 2009 6:35 PM

Clean wheels and good pickups would be a good help. If you ever need any phosphor bronze, I have a four inch wide roll about ten feet long of 0.002 thick phosphor bronze material. I could send you a little in an envelope for free.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    February 2008
  • 419 posts
Posted by UpNorth on Saturday, September 19, 2009 12:49 AM

The Bachmann Shay has both caps and inductors on the DC/DCC bridge card. The caps need to be cut. The inductors can all be removed and replaced with a bridge wire. 

They are all part of the noise suppression section  that is poinless in a DCC environment.  The noise suppression is mainly for  DC only.

Marc 

  • Member since
    January 2004
  • 166 posts
Posted by mmartian22 on Thursday, September 24, 2009 8:41 PM

        i cut the caps. and inductors but still didn't work. so ipulled the board and hardwired it in . i also added contacts to the tender.  it still doesn't run quite right. but it runs better than what it did

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

There are no community member online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!