Why Three Rails?

They also need DC if they are going to run arc lights.

Jim.

Reply to
Jim Guthrie
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OK, how DID that whistle thing work?

How did it know it got a burst of DC in the AC, and why wouldn't it blow all the time if the train was running on DC? Simply, what was the circuit involved?

Reply to
<wkaiser

There are some advantages to DC, but the difficulty in 'transforming' voltages and the losses in long distance transmission far outweigh them. Well before W.W.II most communities and utilities had switched to AC for those reasons. There were some 'hold-outs' however. The smaller systems using DC could use big banks of batteries for inexpensive back up power, as you describe for the phone companies.

AC systems had NO readily available back up power, except for more generators (uneconomical). Modern 'inverters (DC to AC) were NOT available. Only motor-generator ('MG') sets could do DC to AC conversion, and they were very inefficient.

Similarly, only MG sets could do DC to DC voltage conversion acceptably. Very small scale downward conversion could be done with resistance grids, but this is extremely wasteful. Upward voltage conversion required an MG set. Look at most W.W.II military radios and you'll find several small MG sets providing the various DC voltages needed by the radio. Some such MG sets could simultaneously produce several different DC voltages (different windings in the generator part). They were heavy, noisy, and troublesome, but there was no alternative at the time.

Dan Mitchell ============

Reply to
Daniel A. Mitchell

What I SHOULD have said was that the whistles required BOTH AC and DC to work properly. On the other hand, the loco motors and reversing e-unit sequencer couldn't care whether they got AC or DC to work.

Most used an internal relay to activate the whistle. On the usually 60 Hz AC track power the relay would TRY to activate 60 times per second, first one way, then the other. The result, due to the mechanical inertia of the relay, was NO relay motion at all (but usually some buzzing sounds).

Adding a shot of DC with the whistle button on the transformer electrically 'biased' the relay inone direction sufficiently to cause it to trip, closing a contact, that actuated the whistle motor.

So, yes, on pure DC the whistle would likely try to blow all the time. You just had to disconnect the whistle in that case. The train itself would run fine. Many of the really early sets, those most likely to be run under DC conditions, didn't necessarily have whistles anyway.

Dan Mitchell ============

Reply to
Daniel A. Mitchell

That's the problem... the whistle would blow continuously. It had to be disabled by disconnecting a wire in the tender.

There is a DC relay inside the tender, or loco body for diesels.

On steamers, the relay contacts completed the circuit to provide track power to the whistle motor. Compensating windings in the controller ensured a voltage & current boost to provide a little extra power for running the whistle motor in addition to the engine. The loco could be wired to provide the current instead to an electromagnetic release coupler

On diesels, the relay completed a circuit to connect a dry cell (sic) battery to a bicycle-type horn, producing that magical Lionel "bleating".

The locos could be wired to provide the current instead to the reverising "e-unit" (Magic-Electrol) or an electromagnetic release coupler or couplers (Teledyne). See:

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For a better description & excellent wiring diagrams.

Rob

Reply to
trainfan1

Just as you say - if you ran a typical pre-electronic Lionel loco on DC, the universal motor would work fine, and the whistle would blow all the time. Note that you would not have polarity reverse for the direction control, and would still be relying on interruption of the power to cycle the "E-unit" DPDT stepping relay.

The Lionel whistles were small AC motor driving a blower to activate a two chime whistle. There was a small normally open relay which was de-sensitized to AC by the addition of large copper disks at one end of the coil. The relay continually received track power, but would only pick up when about 1.5 VDC was added to the normal 6 to 20 VAC propulsion power. When the whistle relay picked up, it would complete the whistle motor circuit.

Lionel transformers with the "Multi-Control" logo (and often with a "W" in the model number) had built-in whistle controllers that used a copper-oxide rectifier to generate the DC to activate the whistles. The early add-on whistle controllers (no. 167, etc.) also used the copper oxide rectifier. Lionel used a sequential switch contact arrangement to give a short burst of the full 1.5 VDC to pickup the whistle control relay as the control button or lever was first moved, but then as the whistle control went to full travel, added in a parallel shunt resistor to reduce the DC below 1 VDC as a "holding" voltage, and to prevent burning out the copper oxide rectifier (which otherwise had full train and all the car lights, etc. passing through it.) In later years Lionel offered a cheap substitute add-on whistle control that merely switched a D-cell battery in or out of the circuit to the train. Gary Q

Reply to
Geezer

operated on

systems

acceptably.

different

Reply to
crusty-the-clown

Geez, I forgot about the whistle. It's only been 40 years since I rean any Lionel so I guess that my memory isn't what it used to be.

-- Why isn't there an Ozone Hole at the NORTH Pole?

Reply to
Bob May

I had the Command Control and found it to have worked for the 10 years or so I used it as a kid. It was neat to uncouple cars anywhere without having to go over there and do the uncoupling.

-- Why isn't there an Ozone Hole at the NORTH Pole?

Reply to
Bob May

Yep, DC was the power source for some people back then but you didn't run your toy trains with that relatively high voltage!

-- Why isn't there an Ozone Hole at the NORTH Pole?

Reply to
Bob May

Hornby used 20V AC. You are probably thinking of Hornby-Dublo - that used

12V DC.

Hornby was '0 Gauge' tinplate and was both clockwork and electric. Hornby-Dublo was '00 gauge'. Both systems were manufactured by Meccano Ltd.

"Christ> snip

Reply to
Dick Ganderton

Your experience was better than most. A friend had one of these (he STILL has it). After a few months lots of stuff stopped working right. MANY trips to the Lionel repair depot only yielded partial and temporary fixes. This was typical. After a short run, Lionel discontinued the whole concept. It was too expensive to have a big market, and too troublesome to be profitable.

There were LOTS of attempts to use mechanically tuned devices to select between electrical frequencies. Some Radio control systems (model aircraft, etc.) tried to use it. There were all sorts of vibrating reed relays, and vibrating reed frequency meters. I worked on some of this stuff, as a university instrument repairman. Some of the very expensive stuff worked passably, but was always high maintenance. The only lower priced things that worked decently were the frequency meters (I still have a few around somewhere), but they're obsoleted by newer digital solid-state devices. Toy trains were definitely in the low cost (relatively) end of this scale, and suffered accordingly. If it had been made well enough to work dependably, nobody could have afforded it. As it was, few could afford it, and it still didn't work acceptably.

Dan Mitchell ============

Dan Mitchell ============

Reply to
Daniel A. Mitchell

Not DIRECTLY from high voltage DC, NO! SOME DC systems were 110 volt, but many were not. In the early days there was NO standardization.

There were lots of low voltage systems around in rural areas. Many were only 12 or so volts. 32 Volts was also in use. The problem was that you couldn't send the low voltage DC any distance without horrible resistive losses. We still fight with this problem on our layouts today, it's called 'voltage drop'.

The trains could be run from the then common 6-volt batteries, two in series. I remember O-scale layouts with big banks of batteries to power them. You established speed control by BOTH resistance, and by switching in and out various series and parallel combinations of batteries.

The batteries, in turn, could be charged through resistors (to limit current), and 'stacked' in series as needed to match the charging voltage.

Dan Mitchell ============

Reply to
Daniel A. Mitchell

I had a slot car back in the late '50s or early '60s which ran off some of the big old round dry cell. Got an Aurora set later when I was

11 or 12 that had a power pack. Still have that old set (Aurora) come to think of it. I've been dragging it around for decades as I've moved.
Reply to
Rick Jones

Well sort of. It is interesting to review the old Lionel catalogs. In 1902 and 1903, if you didn't want to run your 2 7/8" gauge Electric Express on dry cells, for $0.50, Lionel would supply you with a No. 370 direct current reducing outfit. It consisted of 2 glass jars with two lead plates each that were filled with sulphuric acid diluted 10:1 with water, and wired in series with a 32 candle power lamp running off the household 110 VDC power. The child then connected his track to the two outside lead plates to run his train. (Yes, one rail was at line potential.) The instructions say to replace the sulphuric acid solution when the train ceases to operate. Kids were a heck of a lot more robust back then!!

By 1905, Lionel was instead offering a No. 20 direct current reducing device for $5.00, that employed a built in 50 candle power lamp to drop the voltage and a shunt resistance to allow adjusting the track voltage, all mounted on a slate base and protected with a metal box. In 1908, "a lot of experimenting" lead to a "vastly superior" design that employed "four porcelain tubes carrying resistance wire, perfectly insulated" for $6.00. It was for DC only, and one was to specify the line voltage when ordering. By 1909, Lionel's "scientific researches" allowed a very similar device to be used on AC or DC (purchaser to specify DC voltage or AC voltage and number of cycles). But it still appears one side of the track was still connected to the incoming line - the catalogs make no mention of it but I would hope the instruction sheet described how to make sure that rail was on the grounded line. Gary Q

Reply to
Geezer

In the 'old days' (pre W.W.II, mostly) batteries were commonly available (the the extent that they were available at all) in single cell form ... about 1.2-1.5 volts each cell. Thus a bank of these could provide reasonable speed control just by switching in and out various cell combinations.

The 'wet cells' were mostly lead-acid types just like today, though the nickel-iron 'Edison' cells were also fairly common.

The speed control by battery switching or resistance would work with 'dry cells' as you state, or 'wet cells' equally well. The rechargeable wet cells were far cheaper in the long run, but cost more initially. Obviously, the wet cells were also far more dangerous (acid, hydrogen outgassing, etc.), especially for children to play with.

But, LOTS of things were more dangerous 'back then', and nobody even thought about it much. Such things were often the LEAST of your worries!

Dan Mitchell ============

Reply to
Daniel A. Mitchell

Good post! All or most of these were various forms of resistor banks for dropping the voltage.

And Yes, people didn't worry a lot about safety 'back then'. Life in general was a lot more dangerous (industrial/work dangers, fire, illness, etc.), and such 'details' were not significant in the overall picture. People were TOUGH ... they HAD to be. Those that weren't didn't last long.

I recall reading of various layouts that DID use full 'mains' voltage (often 110 V) on the track to run the trains. Lots of these were fully scratch built set ups. Worse, some were models of electric railroads with working catenary that operated at something like 110 volts. It must have been 'exciting' for the cats and dogs about, as well as the children!

Dan Mitchell ============

Reply to
Daniel A. Mitchell

On Sun, 20 Feb 2005 22:30:12 GMT, Robert claims:

We tried one rail systems, but the trains kept falling over.

Sorry, could not resist.

Cordially, Ken (NY)

email:

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can send mail to snipped-for-privacy@ftc.gov

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Reply to
Ken [NY]
*** I recall reading of various layouts that DID use full 'mains' voltage (often 110 V) on the track to run the trains. Lots of these were fully scratch built set ups. Worse, some were models of electric railroads with working catenary that operated at something like 110 volts. It must have been 'exciting' for the cats and dogs about, as well as the children!

----------------------------------------------------- Especially in a basement with a dirt floor!

Bill Bill's Railroad Empire N Scale Model Railroad:

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Reply to
Bill

Strangely, the idea of a monorail is hardly new. There were some steam powered ones "way back when". The idea sounds good, and can be made to work, but is a mess to put into practice economically. Perhaps the new Mag-Lev trains will finally get it right ... if they succeed at all.

Dan Mitchell ============

Reply to
Daniel A. Mitchell

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