HDTenEightyP/NetNews huggingface dataset:
From: wbrown@bevsun.bev.lbl.gov (Bill Brown)
Newsgroups: rec.models.railroad
Subject: Re: High voltage pulsing?
Date: 27 Aug 92 19:40:37 GMT
Organization: Lawrence Berkeley Laboratory, California
NNTP-Posting-Host: 131.243.192.17

In article <1992Aug26.164153.3061@nmt.edu> al@nmt.edu (Al Stavely) writes:
>This is one advantage of transistor throttles over other kinds.  To a first
>approximation, a transistor is a current source, although how well it can hold
>the current constant is limited by its supply voltage.  I've built several
>simple throttles based on designs from old _Model Railroader_ articles, and my
>experience is that throttles with power transistor output stages give smoother
>running than those with (for example) voltage regulator output stages.
>
Well - that depends.  Most throttle circuits I've seen use either a transistor
in the emitter-follower (common collector) configuration which is certainly a
voltage source, or in an amplifier configuration where the output transistor(s)
is connected in the common emmitter mode but is really acting as a voltage
source due to feedback.

>I don't know why circuit designers these days seem to prefer designing around
>voltage regulators -- perhaps because it's easier or because voltage
>regulators are "more modern".

Three-terminal regulators are commonly used for simple throttles because they
have over-current protection built in.  In addition, only a couple of
additional parts are required.

>But for this particular application, a voltage regulator regulates the wrong
>thing.

I disagree with your conclusions.  In conjunction with permanent magnet DC
motors (about the only type still used in MR work), a stiff voltage source
provides essentially a constant- speed drive.  Regulating current yields
essentially a constant torque drive which, given the mechanical realities 
of the drives in models, generally is not considered to be a "good thing."

The old reostat method was essentially a current-regulated supply (but not
a very well-regulated setup).  Those types of characteristics are about
the last thing I would want to recreate.  But if that's what makes you
happy - Enjoy!

Disclaimer:  These opinions are my own and have	    |
    nothing to do with the official policy or the   |  -bill
    management of L.B.L, who probably couldn't      |   wlbrown@lbl.gov
    care less about employees who play with trains. |
From: btarbox@sw.stratus.com (Brian Tarbox)
Newsgroups: rec.models.railroad
Subject: subway car questions
Date: 31 Aug 92 11:39:44 GMT
Organization: Stratus Computer, Inc.

I would like to add a subway to my layout using the sort of cars
found in Toronto or Boston's Red Line (I know their different, but thats
the 'sort' of car I want).  The only cars I've seen like that are in
the Walther's catalog...in Washington, DC colors I think.

Does anyone have experience with these cars (min. radius in particular)
or suggestions for other such cars?  Thanks very much.
Newsgroups: rec.models.railroad
From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879)
Subject: Re: HO Scale Pantographs
Date: Tue, 1 Sep 1992 16:37:48 GMT
Organization: University of Iowa, Iowa City, IA, USA

In article <1992Aug31.200758.21731@CS.ORST.EDU>
larsons@xanth.CS.ORST.EDU (Larson Shawn Michael) writes:
>The question on model catenary reminded me to ask this question:
>
>Where can you order pantographs in HO scale?

Any Fleischmann or Marklin dealer ought to be able to get you some
pantographs, since both companies sell lots of models equipped with
them, and they sell spares as replacement parts.  Judging by the one
Fleischmann electric engine I own, they're quite durable, and they
ought to run quite well if you've got decent wire overhead.

It is prototypical to run pantographs on trolley wire (as opposed
to catenary).  If you look, for example, at the CSS&SB system, you
find catenary on main line trackage, but single strand (or trolley
wire) on most sidings.  I've seen the same pattern in many european
railroads, and on many Swiss mountain railroads (where low speed
running is the rule), they use simple wire throughout.

				Doug Jones
				jones@cs.uiowa.edu
From: muth@a.cs.wvu.wvnet.edu (Wayne A Muth)
Newsgroups: rec.models.railroad
Subject: Re. [benchwork]: What kind ...
Date: 1 Sep 92 12:47:32 GMT


  >> previous questions ... what kind benchwork ...what wood ...

  My "bible" is "How to Build Model Railroad Benchwork" by Linn
  Westcott [Kalmbach Publishing] $5.95 at most hobby shops.

  I am a disciple of practice as set forth in this book -> benchwork
  very light and durable.  Build it just like the author
  prescribes.

  What kind of wood? -> I don't know what the various grades are
  called.  I buy what I call "framing lumber" ... this is one cut abouve 
  the cheapest stuff...
Newsgroups: rec.models.railroad
From: yves@speedy.dev.cdx.mot.com (Yves Vidal)
Subject: Re: HO Scale Pantographs
Organization: Motorola Codex, Canton, MA
Distribution: rec.models.railroad
Date: Tue, 1 Sep 1992 13:43:26 GMT

In article <1992Aug31.200758.21731@CS.ORST.EDU> larsons@xanth.CS.ORST.EDU (Larson Shawn Michael) writes:
>
>Any help on where pantographs can be ordered would be greatly appreciated.
 
You should try FLEISHMAN or MARKLIN in Germany (expensive) or
simply JOUEF in France (cheap). JOUEF should be able to help you
finding some pantographs. Also try MINITRIX.
Most europeean engines are electric and therefore carry 
pantographs. As a last resort, you can try RIVAROSSI, too.
Good luck.
Yves
From: russ@pta.pyramid.com.au (Russell Day)
Newsgroups: rec.models.railroad
Subject: Re: HO Scale Pantographs
Date: 3 Sep 92 03:35:21 GMT
Organization: Pyramid Technology Corporation, Sydney

>In article <1992Aug31.200758.21731@CS.ORST.EDU> larsons@xanth.CS.ORST.EDU (Larson Shawn Michael) writes:
>>The question on model catenary reminded me to ask this question:
>>
>>Where can you order pantographs in HO scale?
>

The Sommerfeldt catalog has a good range of pantographs.  Their catenary
stuff is great, so I would expect the same of their pantos too.  Cant
help with a US supplier, though.

Russ.
Newsgroups: rec.models.railroad
From: jsm@beam.Princeton.EDU (John Scott McCauley Jr.)
Subject: Re: High voltage pulsing?
Originator: news@nimaster
Organization: Princeton University
Date: Thu, 27 Aug 1992 22:17:25 GMT

[transistors vs regulators for throttles]
In article <25810@dog.ee.lbl.gov> wbrown@bevsun.bev.lbl.gov (Bill Brown) writes:
>
>Three-terminal regulators are commonly used for simple throttles because they
>have over-current protection built in.  In addition, only a couple of
>additional parts are required.
>

Digikey stocks ultra-reliable power transitors from National Semiconductor.
These are the LM 195/295/395 and can drive up to 1.0 A of current and have
over-current protection. I think they cost less than $5 each, but you'll
never have to worry about transitors overheating again!

I have used an audio op-amp (LM1875) to generate a +12 to -12 v swing at 1 A
as I didn't want to have a DPDT direction switch in the circuit. Also
fairly robust.

	Scott
From: shepperd@netcom.com (David Shepperd)
Newsgroups: rec.models.railroad
Subject: Re: High voltage pulsing?
Date: 30 Aug 92 23:05:51 GMT
Organization: Netcom - Online Communication Services  (408 241-9760 guest)
X-Newsreader: Tin 1.1 PL4

jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes:
: Why not make a power supply that is a current source, not a voltage source.

I (still) know little or nothing about motors in general but a few years ago I
built a little circuit that allowed my PC to control the voltage delivered to
and measure the current drawn from my HO engine. I intended that the program
could figure out that the engine had stalled and take corrective action, which
I believe is the same goal that you are after.

It is my observation that, at least for the few engines that I have, the
current they draw is fairly constant across all the speeds the engine can
run with any given load. I.e. the current varied directly with the load and
virtually not at all with the speed. Once the armature started spinning and
the current stabilized to its "home" value (~300-500ma, I think), then changes
to the voltage would change the RPM and changes in the load would change the
current. (Until the armature is spinning, the motor represents a pure
resistive load with the current flow being directly proportional to the
volatge applied; it always takes a "high" voltage and consequently a "high"
current to get the armature spinning, or visa-versa).

This implies to me that using a constant current source would make it
difficult to control the speed of a train, although it would probably run
pretty well at any given speed as long as the train didn't change load (such as
go up or down a hill). This seems to follow with the experiences of those who
have made such a beast. It also follows with those who contend that constant
voltage supplies provide better performance. Since the voltage seems to
control the RPM, having a rock solid voltage source would provide the most
consistant train speeds over the varying loads imposed by the track.

You might try hooking up a current meter (or a scope) to your track and watch
the current flow through your engine(s) at various speeds and loads to see if N
gauge motors behave the same as HO (my guess is that they do).

Then again, I could have missed something and am completely wrong.
-- 
Dave Shepperd.          shepperd@netcom.COM  or  netcom.netcom.com!shepperd
The company probably doesn't know what I say or do, but they pay me anyway.
From: Joe.Russ@mixcom.mixcom.com (Joe.Russ)
Newsgroups: rec.models.railroad
Subject: Tracks Ahead returns to PBS
Date: 31 Aug 92 01:12:15 GMT
Article-I.D.: mixcom.1992Aug31.011215.10570
Distribution: usa
Organization: Milwaukee Internet Xchange BBS, Milwaukee, WI U.S.A.


On November 14 (in the Milwaukee, Wis. area) the first of 13 new
episodes of the Channels 10/36 produced program "Tracks Ahead" will
air on Channel 10 at 6:30 p.m. The Saturday evening program will have
a new look to it as the previous host, Charles Zehner, has become the
show's senior producer and correspondent while Ward Kimball has taken
over the hosting duties. It also differs from the first series as it
now covers railroading in Europe.
 
The series is funded in part by Kalmback Publishing and W.K. Walthers,
Inc. It will be distributed to over 200 PBS stations soon.
  Joe R.
-- 
Joe.Russ@mixcom.com
From: ap096@cleveland.Freenet.Edu (Kevin P. Dahlhausen)
Newsgroups: rec.models.railroad
Subject: Re: Thomas the Tank Engine Layout
Date: 3 Sep 1992 22:46:18 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: ap096@cleveland.Freenet.Edu (Kevin P. Dahlhausen)
NNTP-Posting-Host: slc10.ins.cwru.edu


In a previous article, turner@ssdt-tempe.sps.mot.com (Robert Turner) says:

>In the U.S.A. a children's show called "Shining Time Station" appears to
>use an HO layout for  "animated" features about Thomas the Tank Engine
>and his friends Gordon, James, Henry, and ...
>
>OR I think it is an HO layout.  Does anybody know about the train layout
>used in the filming of these segments?

Yes, all my nephews are hooked on the show! 

The scale looks larger than HO.  I would guess it is an LGB layout.
(G gauge?)
 
>Robert Turner (602) 897-5441 Semiconductor Systems Design Technology, Motorola
>turner@ssdt-tempe.sps.mot.com   OR   ...!uunet!dover!turner
>GOD is real, unless declared integer. --J. Allan Toogood
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

I like it.
From: sra@bistromath.mitre.org (Stan R. Ames)
Newsgroups: rec.models.railroad
Subject: Re: High voltage pulsing?
Date: 26 Aug 92 14:53:01 GMT
Organization: The MITRE Corporation, Bedford, MA

In article <17e88sINNmae@darkstar.UCSC.EDU> haynes@cats.ucsc.edu (Jim Haynes) writes:
>
>I don't keep up with the model railroad literature, so maybe this is a
>dumb question or an old idea; but I was wondering if one could get
>by with less track cleaning by using higher voltage pulsing to run
>the locomotive.  I remember from some treatise on electrical contacts

That is exactly the concept behind the signal being proposed for the NMRA
standard on command control.  This approach developed by Lenz electronics
uses +-18 volt square waves to transmit commands to receivers within
locomotives.  It has the properties relative to track cleaning that you desire.

Stan
From: awhichel@robin.rp.csiro.au (Adrian Whichello)
Newsgroups: rec.models.railroad
Subject: Request: Anorak Sketch and names for railfans
Date: 30 Aug 92 08:17:00 GMT
Organization: CSIRO Division of Radiophysics/Australia Telescope National Faci
News-Software: VAX/VMS VNEWS 1.41

Hi Netland

can someone please give me some details of "Jasper Carrott's infamous Anorak
sketch" mentioned in the Misc. column of MRJ 55? Thanks... 

Names for railfans: well how about gunzels, sandwiches, toasted sandwiches,
retreads... (I know the last three are also used by psych nurses to describe
patients!) please tell me some more,

							Adrian Whichello 
Newsgroups: rec.models.railroad
From: al@nmt.edu (Al Stavely)
Subject: Re: High voltage pulsing?
Organization: New Mexico Tech, USA
Date: Mon, 31 Aug 1992 15:55:05 GMT


In article <v6gngnc.shepperd@netcom.com> shepperd@netcom.com (David Shepperd) writes:
>
>It is my observation that, at least for the few engines that I have, the
>current they draw is fairly constant across all the speeds the engine can
>run with any given load. I.e. the current varied directly with the load and
>virtually not at all with the speed....
>
>You might try hooking up a current meter (or a scope) to your track and watch
>the current flow through your engine(s) at various speeds and loads to see if N
>gauge motors behave the same as HO (my guess is that they do).

I've done this (as I just posted in another message), and this sure isn't the
case with my N scale diesels.  With constant load, when the current goes up so
does the speed.  The relationship is far from linear, but it's also far from
constant.


-- 

	- Allan Stavely, New Mexico Tech, USA
Newsgroups: rec.models.railroad
From: gregg@pinot.zehntel.com (Gregg Fuhriman)
Subject: Re: benchwork: a case study
Reply-To: gregg@pinot.UUCP (Gregg Fuhriman)
Organization: Zehntel, Inc. Walnut Creek, CA
Distribution: na
Date: Tue, 1 Sep 1992 20:16:37 GMT

My layout is built to fit in a bedroom.  I knew it would need to be moved
at least once during its construction, so I built the benchwork in a portable
fashion as follows:

After designing the track plan, I used 1x4 pine to build a number of "boxes"
that fit the room and the trackplan.  The boxes range in size from 2' x 4'
to 3' x 6', and fit together like a puzzle.  I used carpenter's glue, nails,
and in some cases #8 wood screws, to hold the 1x4's together.  Another net.user
suggested sheet-rock screws ... this sounds like a good idea to save time.
I used pine because it is cheap, easy to cut and screw, and is easy to find.

The boxes are held to one another by 1/4" hardware (bolts, washers, wingnuts).
For stability, I used at least two bolts for every face that was to be joined.
This is where the portability comes in ... to move the benchwork, just pull
out the bolts.  The boxes are small and light for easy transportation.

Each box has 1x4 or 1x2 cross members every 12 to 16 inches.  These are used to
attach the track risers.  I reccommend using 1x4 for all cross members, as it
is more sturdy and provides a larger surface for attaching track risers.

My layout is free-standing because I wanted to do a minimum amount of damage
to the bedroom walls.  I made all my legs interchangable to make a move that
much easier.  They have two 2x2 pine vertical members, held together at the
bottom by a 1' horizontal length of 1x2 (which rests flat on the floor).
The tops of the 2x2 members are then bolted into the benchwork boxes using
1/4" hardware (these bolts are longer, so they'll go through the 2x2 legs).

To stabilize the layout from "rocking", I attached 1x4 "plugs" to the
outermost faces of the layout, which push against the bedroom walls.  These
have a small piece of old carpeting to pad against the wall to avoid damage.

Have fun building your layout !
					Gregg Fuhriman
From: cal@ee.ryerson.ca (Calvin Henry-Cotnam)
Newsgroups: rec.models.railroad
Subject: Re: Thomas the Tank Engine Layout
Date: 4 Sep 92 11:57:16 GMT
Organization: Ryerson Polytechnical Institute, Toronto

In article <a5ms022K20cy01@JUTS.ccc.amdahl.com> czl30@DUTS.ccc.amdahl.com (Chris Lee) writes:
>
>The Thomas stuff was lifted from a British series called "Thomas the Tank
>Engine and Friends", originally narrated by the ex-Beatle, Richard
>Starky, a.k.a. Ringo Starr.

Ringo narrated the first season of 20 episodes.  Since then, the
part of Mr. Conductor has been played by George Carlin.

Yes, George Carlin actually appears on a show for children!


Calvin Henry-Cotnam, CATE            |    MY CANADA INCLUDES CANADIANS!
Ryerson Polytechnical Institute      | I would really like this to include
Toronto, Ontario, Canada             | Quebec - but I won't hold my breath.
From: falken@apple.com (Dave Falkenburg)
Newsgroups: rec.models.railroad
Subject: Clubs in the San Jose Area?
Date: 29 Aug 92 00:29:13 GMT
Organization: Apple Computer, Inc.
X-Useragent: Nuntius v1.1.1d9
X-Xxdate: Fri, 28 Aug 92 01:27:35 GMT


I'm new to the Santa Clara Valley area and was wondering if someone could
give me any information about local model railroading clubs. 
Specifically, is there an N-TRAK group?

-Dave Falkenburg
-falken@apple.com
-Disclaimer: I just work for Apple, I don't speak for them!
From: Joe.Russ@mixcom.mixcom.com (Joe.Russ)
Newsgroups: rec.models.railroad
Subject: Trainfest '92 in Milwaukee, Wis.
Date: 3 Sep 92 17:50:18 GMT
Article-I.D.: mixcom.1992Sep03.175018.21456
Distribution: usa
Organization: Milwaukee Internet Xchange BBS, Milwaukee, WI U.S.A.


On November 14 & 15, 1992, the Wisconsin Southeastern (WISE) Division
of the National Model Railroad Assocation (NMRA) will host its 21st
annual Trainfest '92 at  Wisconsin State Fair Park's North Exhibit
Hall located at 84th St. and Greenfield Ave. in West Allis, Wis. The
show, the one Russ Larson of MODEL RAILROADER said was "...one of the
best, if not THE best, model railroad show in the country," (February
1992 MR) features over 92,000 square feet of exhibits, with over 25
operating layouts in scales from Z to G, numerous hobby shops from
across the country, manufacturer's including W.K. Walthers, Inc. and
Kalmbach Publishing, and other exhibitors including railroad artists,
historical societies, museums. The show also has a video theater and
test track. And there is plenty of free parking!
 
 Admission donations are as follows:
 -----------------------------------
 $4 for adults
 $3 for seniors and NMRA members
 $2 for children 12-18
 Under 12 free with parent
 
 Hours are:
 ---------------------------------------
 Saturday, November 14, 10 a.m. to 6 p.m.
 Sunday, November 15, 10 a.m. to 5 p.m.
 
To get there exit I-94 (from either west or south) at 84th St. and
head south. You won't miss the fair park on your left. Make plans now
to attend.
 Joe Russ
 WISE Div., NMRA
 
 Advertisement: For a schedule of other railroad and modelrailroad
events in the Milwaukee area, see the Hobby Zone on the Safe Harbor
BBS (414)548-8140.
-- 
Joe.Russ@mixcom.com
Newsgroups: rec.models.railroad
From: steven@luna.rivm.nl (Steven van Uitert)
Subject: Re: HO Scale Pantographs
Organization: Rijksinstituut voor Volksgezondheid en Milieuhygiene,Bilthoven,NL
Date: Wed, 2 Sep 1992 07:23:56 GMT

In article <EDVAX.92Sep1204154@pyrite.usenet> edvax@pyrite.SOM.CWRU.edu (Weyland Yutani Ltd) writes:
	|
	|
>		SOMMERFELDT GmbH
>		Friedhofstrasse 42
>		7323 Hattenhofen
>
>		Telephone:	07164/3195
>		FAX:		07164/5786
>
>Now is that Germany or Austria? It doesn't say.

It is Germany. Sommerfeldt however doesn't sell to private persons.
But I really can't believe you cannot have it from Walthers.

Steven van Uitert
From: shorrow@oasys.dt.navy.mil (Paul Shorrow)
Newsgroups: rec.models.railroad
Subject: Re: benchwork: a case study
Date: 2 Sep 92 15:03:14 GMT
Reply-To: shorrow@oasys.dt.navy.mil (Paul Shorrow)
Distribution: na
Organization: Carderock Division, NSWC, Bethesda, MD

In rec.models.railroad, muth@a.cs.wvu.wvnet.edu (Wayne A Muth) writes:
>  inches -- so then I proceeded to cut 3" off of 3 legs and 4" off
>  the fourth.  Instead of the old axiom of "measure twice, cut
>  once", I apparently need more than "measure twice" ...
>
 When I initially built my L girder table I had made it 48" high...
 after a couple of days I lowered it to 43" .....so I could reach
 everything ....
 Now that I'm in the proccess of wiring and hooking up, I picked up
 my layout and set it on blocks so I could work under it without
 banging my head every 2 minutes |-) 
 
 ...bifocals,hot soldering irons, and a low overhead are not compatible....

 My layout is 18x4 ft and is light enough to move (a short distance)
 another plus for L girder construction. 

 Just my $0.02
 Paul Shorrow
From: edvax@pyrite.SOM.CWRU.edu (Weyland Yutani Ltd)
Newsgroups: rec.models.railroad
Subject: Re: HO Scale Pantographs
Date: 1 Sep 92 20:41:54
Organization: Ozone Depleting Shoulder Launched Stealth FAXs, Inc.
	<1992Aug31.200758.21731@CS.ORST.EDU> <25892@dog.ee.lbl.gov>
	<2429@tymix.Tymnet.COM>
NNTP-Posting-Host: pyrite.som.cwru.edu
In-reply-to: romeo@niagara.Tymnet.COM's message of 1 Sep 92 17:41:53 GMT


   In article <1992Aug31.200758.21731@CS.ORST.EDU>
   larsons@xanth.CS.ORST.EDU (Larson Shawn Michael) writes:
   >The question on model catenary reminded me to ask this question:
   >
   >Where can you order pantographs in HO scale?

   Any Fleischmann or Marklin dealer ought to be able to get you some
   pantographs, since both companies sell lots of models equipped with
   them, and they sell spares as replacement parts.  Judging by the one
   Fleischmann electric engine I own, they're quite durable, and they
   ought to run quite well if you've got decent wire overhead.
--------------------------

You might also wish to check out Sommerfeldt. They make the most
authentic catenary (double wire, counterweights, pulleys,  etc) of any
European HO that I've seen.  They also make pantographs. I have their
1989 catalog that I picked up from AMRO LTD.  They do a lot of mail
order buisiness.  But the stuff is so expensive (3-5 dollars per mainline 
mast!). Their address is:
		AMRO Ltd.
		121 Lincolnway west
		New Oxford, PA 17350

or Sommerfeldt's address:
		SOMMERFELDT GmbH
		Friedhofstrasse 42
		7323 Hattenhofen

		Telephone:	07164/3195
		FAX:		07164/5786

Now is that Germany or Austria? It doesn't say.

Hope this helps,

--ed

--
Bus error, core dumped
Newsgroups: rec.models.railroad
From: turner@ssdt-tempe.sps.mot.com (Robert Turner)
Subject: Thomas the Tank Engine Layout
Reply-To: turner@ssdt-tempe.sps.mot.com (Robert Turner)
Organization: Semiconductor Systems Design Technology, Motorola, Tempe AZ
Date: Thu, 3 Sep 1992 20:00:30 GMT

In the U.S.A. a children's show called "Shining Time Station" appears to
use an HO layout for  "animated" features about Thomas the Tank Engine
and his friends Gordon, James, Henry, and ...

OR I think it is an HO layout.  Does anybody know about the train layout
used in the filming of these segments?

The layout is very impressive in its details.  I have a couple of children's
story books with photographs of the layout that show an incredible amount of
detailing in the track and the landscape.  Check of these story books for what
can be done with a fairly large budget.

FYI: the closing credits has some nice helicopter shots of a steam train
speeding across a lovely green countryside.  Too short, however.

Any information floating around out there in net-land?

Robert
-- 
Robert Turner (602) 897-5441 Semiconductor Systems Design Technology, Motorola
turner@ssdt-tempe.sps.mot.com   OR   ...!uunet!dover!turner
GOD is real, unless declared integer. --J. Allan Toogood
Newsgroups: rec.models.railroad