Friday, October 15, 2010

SoundBytes XXIIX

SoundBytes XXIIX

Its time for another edition of SoundBytes. This time we will review George’s trip to Oregon and California. We will also fill you in on our upcoming schedule for shows. Finally, for our tech tip, we will discuss the capacitor found on Tsunami decoders and their purpose.

Oregon and Northern California Trip
George would like to issue a thank you to those he was able to visit on his recent trip. He was able to give clinics for many of the clubs in the area that he was traveling and saw lots of great layouts. George visited the Columbia Gorge Model Railroad Club (,

the Mount Hood Model Engineers, both in the Portland, Oregon area. In the Northern California area, He was able to visit the Carquinez Model Railroad Club in Crockett (,

the Alameda County Central Railroad Society in Pleasanton (

and the East Bay Model Engineer Society at the Golden State Model Railroad Museum in Richmond (
He was happy to be able to spend some time with these club members showing the capabilities and features of the Tsunami decoders.
During this trip, he also visited several SoundTraxx and Blackstone Models authorized dealers in the area. He was able to visit Whistlestop Trains (
and The Hobbysmith (,
both in Portland, OR, Mainline Trains in Forest Grove, OR,

Tammie’s Hobbies ( in Beaverton, OR

and Eugene Toy and Hobby in Eugene OR.
Stops in California included The Train Shop in Santa Clara, CA,
Tom’s Trackside Trains ( in Menlo Park, CA,
Railroad Hobbies ( in Roseville, CA,
Bruce’s Train Shop (, in Sacramento, CA,
Roger’s Railroad Junction ( in Lodi, CA,
Franciscan Hobbies ( in San Francisco, CA and Just Trains ( in Concord, CA. Just Trains was holding their annual Open House Sunday, October 3rd.
This year had a good crowd that lasted all day. There were lots of great layouts on display, including an HOn3 Blackstone Models inspired layout by Bill Iwan,
a member of the Northern California Narrow Gaugers,
a great On30 modular layout club.
This was a busy trip, but he had a good time, despite the traffic! If you live in these areas, or are just visiting, be sure to visit these fine dealers.

Upcoming Shows
This week, Nancy, Jarrette and George will be in Chicago for the International Hobby Expo ( This will be held at the Rosemont Convention Center in Rosemont, IL, near the Chicago O’Hare International Airport. If you are in the area, come by and see what we have to show.
November 12, 13, and 14th, we will be at Trainfest in Milwaukee ( Following that, we will be at the Oklahoma City Train Show, ( December 4th and 5th. Be sure to come by if you are in the area to see what’s new and to see some of the upcoming releases from Blackstone Models!

Tech Tip:
ch There seems to be confusion as to the purpose of the Capacitor included in the Tsunami decoders. This is a 220uf capacitor that is designed as a stay-alive capacitor for the processor. Older SoundTraxx decoders had a 33uf bi-directional capacitor included to hook up in line with the speakers. This was a noise filter and is no longer necessary with the Tsunami line of decoders. Lets look at how it works.
At any point in time, the locomotive is picking up power from one wheel on each rail, no matter how many wheels it has.

Electricity follows the shortest path of least resistance, which will be one wheel on each rail. As the locomotive is moving, this point of contact with the rail is broken and needs to be re-established quickly, which it does, but for that moment, the decoder is without power. The capacitor supplies the processor with power until another reliable path of electricity is found. This window is only milliseconds long, but with a sound decoder, even this is enough to result in a constantly re-setting sound decoder, similar to plugging in and unplugging a computer. With a non-sound decoder, this takes place so fast that we never see any interruption of power, but with sound, we would hear the loss of power.
We have selected a 220uf capacitor because on a well-wired layout, these interruptions of power will only last ¼ second to ½ second. This capacitor is more than enough to handle this amount of time. If you are still experiencing losses of power causing interruption of operation, you can increase the capacitance to help lengthen the amount of time that the processor will be powered over dead track. Remember, as capacitance increases, so to does the physical size of the capacitor, which may be a tight fit into small locomotives. You can use as large a capacitor as you can fit, but we do recommend keeping it less than 1000uf. If the capacitance of multiple locomotives gets too high, this could cause the DCC system to detect a short circuit upon startup due to the inrush current caused by multiple capacitors charging at the same time. Most installations will not need this, however, if the locomotive’s track power pickups are insuffecient (not enough wheels are picking up power), this could help overcome these issues.