Re: Diode Constant Lighting
This is where some of the confusion comes in.? The way Digitrax creates the waveform (and it is not the only possible way) is to hold one "Rail A" at common and apply +14 VDC (approx) to "Rail B."? Then to hold "Rail B" at common and apply +14 VDC (approx) to "Rail A."? The result ACROSS THE RAILS is an AC voltage that is 28 volts peak-to-peak, 14 volts peak, and 14 volts rms.
Some argue that there can be no AC "because there is no negative voltage anywhere."? This is true relative to the power supply common, but the DCC voltage is NOT relative to that common, but from rail to rail.
Charles E. "Chuck" Kinzer
On Thursday, February 27, 2025 at 04:07:29 AM PST, Anthony Salvate via groups.io <n1tks@...> wrote:
It is AC. And the rails act as a transmitting antenna. If you tried to turn on your AM radio while your DCC equipment is on, the noise from the DCC overrides the strongest AM station! Regards,
On Feb 27, 2025, at 2:16?AM, Charles Kinzer <ckinzer@...> wrote:
?
AC isn't being mimicked.? It IS AC.? It just happens to be a square wave.? There is a lot of confusion about this due to some other naming conventions.? Most notably "Bi-polar DC" which is a term also used elsewhere in electronics.? By definition, DC cannot be bipolar, so it is just a descriptive term.
I'm pretty sure that the actual light output would cut in half as the waveform has a 50% duty cycle.? Not necessarily compared to 12 VDC, but whatever the RMS voltage of the AC waveform is (which is the same as peak voltage since it is square wave) which is usually a bit higher than 12 volts for DCC unless for N scale.
I don't know if the human eye, or brain, would perceive it as half brightness, however.
To get way down in the weeds, LEDs are typically specified with a maximum reverse voltage of 5 VDC.? What saves them from serious damage is the series resistor.? However, damage can accumulate over time from a sort of micro damage to areas of the junction.? It is probably highly unlikely anyone would see this get to the point of a failure.? People do it all the time.? But it is a circuit that violates a specified limit, and an electronics engineer is likely to avoid a design applying excessive AC to LEDs.
Charles E. "Chuck" Kinzer
?
On Wednesday, February 26, 2025 at 10:10:16 PM PST, Kim Hartshorn via groups.io <w.kim.hartshorn@...> wrote:
I noticed that an LED wired directly across DCC rails will light no matter which lead goes to which rail.? Is this because of the split phase version of DC which sort of mimics AC?? So the diode is only responding to the half wave...does that mean it is at half intensity as compared to pure 12v DC?
?
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Re: Diode Constant Lighting
Hey there
GREAT QUESTION?
Looking forward to the answer!!!!!
Roger Haag. ? ? ? S scale man
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On Feb 27, 2025, at 9:47?AM, Kim Hartshorn via groups.io <w.kim.hartshorn@...> wrote:
?
So this is where,?i think, there is confusion.? My understanding...and I could be totally wrong, is that DCC puts a half wave on each rail so that one rail, for the sake of argument, is a 6v square wave from the 'top' of the wave to neutral.?
In other words 30 pulses and the other rail is the bottom half of the wave -6v from neutral to the 'bottom' of the wave.Each 180 degrees out of phase with each other.? And wiring across the waves results in 12v AC.? In other words there is no 'neutral' rail
with a full square +6 to -6 wave on the other rail.? Each rail by itself represents a square wave DC current to neutral, only when bridged do we get AC.
Does this sound right?
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Re: Back To Modeling, Sorta...
I wish the Pine Canyon kits were still available, they were very nice.? I built a small number of them, including the Rigsby Terminal kit which I had to modify to fit.? Cutting the walls was a bit messy, but not hard to do.? I used a table saw with a carbide blade, which made a bit of a mess, but that's why we have shop vacs!? The layout may never be done, but the building fits nicely now.?
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Jerry Poniatowski
Brighton, MI
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Re: Diode Constant Lighting
So this is where,?i think, there is confusion.? My understanding...and I could be totally wrong, is that DCC puts a half wave on each rail so that one rail, for the sake of argument, is a 6v square wave from the 'top' of the wave to neutral.? In other words 30 pulses and the other rail is the bottom half of the wave -6v from neutral to the 'bottom' of the wave.Each 180 degrees out of phase with each other.? And wiring across the waves results in 12v AC.? In other words there is no 'neutral' rail with a full square +6 to -6 wave on the other rail.? Each rail by itself represents a square wave DC current to neutral, only when bridged do we get AC.
Does this sound right?
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Re: Back To Modeling, Sorta...
Yes, the material used in the Pine Canyon Modules does have a pronounced Oder when cutting or sanding, but they make great models. I have to say, I have several DSL Models and they are also very nice, bout the odor from cutting into the DSL kits is much more pronounced! Stephen J Kutash
203 906-5116 (Cell)
On Wed, Feb 26, 2025 at 09:38 AM, Bob Werre wrote:
Those Pine Canyon kits were great and not that hard to build.? Modifications were a bit more difficult as it's hard to add or sever wall sections.?
Actually... I've cut many Pine Canyon kit walls using my chop/miter saw and a fine tooth blade (60 TPI, I believe). When I used this blade to cut MDF building cabinets, it produced a wood powder as fine as "powdered sugar." When I used this blade to cut Pine Canyon walls, the blade produced a fine shredded "mozzarella cheese." It is a very messy process, even with a vacuum attached to the saw, but it produces very smooth wall cuts.
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Phil Scandura
Flagstaff AZ
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Re: Back To Modeling, Sorta...
On Wed, Feb 26, 2025 at 09:38 AM, Bob Werre wrote:
Those Pine Canyon kits were great and not that hard to build.? Modifications were a bit more difficult as it's hard to add or sever wall sections.?
Actually... I've cut many Pine Canyon kit walls using my chop/miter saw and a fine tooth blade (60 TPI, I believe). When I used this blade to cut MDF building cabinets, it produced a wood powder as fine as "powdered sugar." When I used this blade to cut Pine Canyon walls, the blade produced a fine shredded "mozzarella cheese." It is a very messy process, even with a vacuum attached to the saw, but it produces very smooth wall cuts.
?
Phil Scandura
Flagstaff AZ
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Re: Diode Constant Lighting
It is AC. And the rails act as a transmitting antenna. If you tried to turn on your AM radio while your DCC equipment is on, the noise from the DCC overrides the strongest AM station! Regards,
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On Feb 27, 2025, at 2:16?AM, Charles Kinzer <ckinzer@...> wrote:
?
AC isn't being mimicked.? It IS AC.? It just happens to be a square wave.? There is a lot of confusion about this due to some other naming conventions.? Most notably "Bi-polar DC" which is a term also used elsewhere in electronics.? By definition, DC cannot be bipolar, so it is just a descriptive term.
I'm pretty sure that the actual light output would cut in half as the waveform has a 50% duty cycle.? Not necessarily compared to 12 VDC, but whatever the RMS voltage of the AC waveform is (which is the same as peak voltage since it is square wave) which is usually a bit higher than 12 volts for DCC unless for N scale.
I don't know if the human eye, or brain, would perceive it as half brightness, however.
To get way down in the weeds, LEDs are typically specified with a maximum reverse voltage of 5 VDC.? What saves them from serious damage is the series resistor.? However, damage can accumulate over time from a sort of micro damage to areas of the junction.? It is probably highly unlikely anyone would see this get to the point of a failure.? People do it all the time.? But it is a circuit that violates a specified limit, and an electronics engineer is likely to avoid a design applying excessive AC to LEDs.
Charles E. "Chuck" Kinzer
?
On Wednesday, February 26, 2025 at 10:10:16 PM PST, Kim Hartshorn via groups.io <w.kim.hartshorn@...> wrote:
I noticed that an LED wired directly across DCC rails will light no matter which lead goes to which rail.? Is this because of the split phase version of DC which sort of mimics AC?? So the diode is only responding to the half wave...does that mean it is at half intensity as compared to pure 12v DC?
?
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Re: Diode Constant Lighting
AC isn't being mimicked.? It IS AC.? It just happens to be a square wave.? There is a lot of confusion about this due to some other naming conventions.? Most notably "Bi-polar DC" which is a term also used elsewhere in electronics.? By definition, DC cannot be bipolar, so it is just a descriptive term.
I'm pretty sure that the actual light output would cut in half as the waveform has a 50% duty cycle.? Not necessarily compared to 12 VDC, but whatever the RMS voltage of the AC waveform is (which is the same as peak voltage since it is square wave) which is usually a bit higher than 12 volts for DCC unless for N scale.
I don't know if the human eye, or brain, would perceive it as half brightness, however.
To get way down in the weeds, LEDs are typically specified with a maximum reverse voltage of 5 VDC.? What saves them from serious damage is the series resistor.? However, damage can accumulate over time from a sort of micro damage to areas of the junction.? It is probably highly unlikely anyone would see this get to the point of a failure.? People do it all the time.? But it is a circuit that violates a specified limit, and an electronics engineer is likely to avoid a design applying excessive AC to LEDs.
Charles E. "Chuck" Kinzer
?
On Wednesday, February 26, 2025 at 10:10:16 PM PST, Kim Hartshorn via groups.io <w.kim.hartshorn@...> wrote:
I noticed that an LED wired directly across DCC rails will light no matter which lead goes to which rail.? Is this because of the split phase version of DC which sort of mimics AC?? So the diode is only responding to the half wave...does that mean it is at half intensity as compared to pure 12v DC?
?
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Re: Diode Constant Lighting
I noticed that an LED wired directly across DCC rails will light no matter which lead goes to which rail.? Is this because of the split phase version of DC which sort of mimics AC?? So the diode is only responding to the half wave...does that mean it is at half intensity as compared to pure 12v DC?
?
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Sorry, that was meant to be just to Ken...
Good to hear Peter but Ron is a bit of a shady fellow so I understand why he came to that conclusion....
--
Ken Zieska
1/64th Scale Modeler
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Ken, When's your next trip to mrim? Tommy?
Good to hear Peter but Ron is a bit of a shady fellow so I understand why he came to that conclusion....
--
Ken Zieska
1/64th Scale Modeler
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Good to hear Peter but Ron is a bit of a shady fellow so I understand why he came to that conclusion....
--
Ken Zieska
1/64th Scale Modeler
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Gents........
Things are slow, eh???
I'm happy (almost smiling) to bring three pair of MTH trucks to your attention.? Make me smile with your best reasonable offer and the trucks will be in your mailbox very quickly.
If I don't smile, they will move along to eBay and elsewhere eventually.
Email preferred.? Phone works.? ??
Loizeaux? aht? SBC? //? Global? daht? net? ? ? ? ? 1-650-962-1577
Happy daze are here again..........Ed Loizeaux
-- Ed Loizeaux Los Altos, CA
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Re: Back To Modeling, Sorta...
Nice start. Rich ?? I bought two of S
Scenery's resin depot kits years ago that had Reading as the
prototype as I recall.? I wasn't aware of the Mount Blue or I
would have gone that way, but then again most all small stations
are similar.? I also built a Mini Structures 2 story station about
that same time.? It's a SP prototype, even though Bill Banta cut
some SOO line stations the actual difference are small.? And when
built close to the tracks, there isn't much room for size
differences 20 years later.? Unless I can clone my self 25 years
earlier, they'll have to do!
As to the Pine Canyon gas station, I
also built one.? Mine also spent years in storage. ?? One of the
smaller cities West of here just off the I-10 freeway contains a
version of it, so they do survive.? Mine is too large for the
layout so I put it on one of our modules, problem with that is we
don't have the ability to actually display it anymore.? I
decorated mine for Phillips 66--I also made a boo-boo in it's
construction but nobody will know!.?
Might have some photos someplace.?
Those Pine Canyon kits were great and not that hard to build.?
Modifications were a bit more difficult as it's hard to add or
sever wall sections.?
Bob Werre
PhotoTraxx
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As things appeared to have slowed down, I offer my latest
projects for the G&MP.
?
The depot is a laser cut Mount Blue kit? based on a standard
C.M. & St. P. design.?
?
Also in the works is an old Pine Canyon gas station that's
been kicking around in storage.? I'm kinda alternating between
the two projects, both are at the sub-assembly stage waiting for
me to get up the enthusiasm for painting before final assembly.
?
Rich G(ajnak)
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Anyone modeling the southwest adding this as a scene to your layout? ;-)
Train heists in remote desert areas of the West have netted millions in Nike shoesIn 2025, robbers aren’t going for gold or money on trains. They're targeting Nike shoes and electronics in heists that sound straight out of the Wild West. Read in USA TODAY:
Shared from
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Re: Back To Modeling, Sorta...
Cool to see the WIP shots.
?
It is always good to have things/options to move between while waiting for one or the other to dry....whether that's glue or paint!
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Bill
Philadelphia
On 02/26/2025 10:35 AM EST Rich Gajnak via groups.io <rustytraque@...> wrote:
?
?
As things appeared to have slowed down, I offer my latest projects for the G&MP.
?
The depot is a laser cut Mount Blue kit? based on a standard C.M. & St. P. design.?
?
Also in the works is an old Pine Canyon gas station that's been kicking around in storage.? I'm kinda alternating between the two projects, both are at the sub-assembly stage waiting for me to get up the enthusiasm for painting before final assembly.
?
Rich G(ajnak)
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Back To Modeling, Sorta...
As things appeared to have slowed down, I offer my latest projects for the G&MP.
?
The depot is a laser cut Mount Blue kit? based on a standard C.M. & St. P. design.?
?
Also in the works is an old Pine Canyon gas station that's been kicking around in storage.? I'm kinda alternating between the two projects, both are at the sub-assembly stage waiting for me to get up the enthusiasm for painting before final assembly.
?
Rich G(ajnak)
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Just quiet it seems.
A couple of threads were locked, nobody given the boot.
Pieter Roos
On Tuesday, February 25, 2025 at 03:54:39 PM EST, Ron Kemp via groups.io <rgkemp316@...> wrote:
Is today a quiet day or have I been excommunicated?
R
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Is today a quiet day or have I been excommunicated?
R
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Do you want a Detroit & Mackinac SHS twin hopper?
? There is a set of 3 of the D&M hoppers on eBay.? I only want one.? Just curious if some one or some others might want one or both of the other two.? I will make a lower bid and see what happens.? Spilt cost one third each car of course.
? I have a video of one hauling gravel out of a Michigan gravel pit.
? If interested please use the button for off-line reply.? Please do not reply on-line.
?
Thanks,
George Courtney
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Roger Haag
Jerry Poniatowski
pscandura
Tom Lennon
Bob Werre
