Lionel SOS, how is it supposed to work?

the older SoS tenders did not have a whistle.  you would have to hook the wire from the tender to the engine for it to really do anything.  A lot of the older boards were held to the frame w/ foam. As it ages, the foam crumbles. If the board touches the metal frame it will short it.

Some SOS boards did have a whistle but the whistle button that came with them would burn out so they stopped using that board. You can see if it works, power up the tender and touch the wrapped wire to the center rail. If you get a static sound it works.

There are people participating on this board who know a lot more about Lionel sound boards than I. My experience with them is limited. Still:

The Sound of Steam only boards that I have seen only have two power wires, one to ground and the other to the locomotive. The locomotives have a switch built into the smoke unit to send pulses of power to the board, making the chuffing sound.

The Sound of Steam & whistle boards that I have seen have three wires: one to center rail, one to ground, and one to the locomotive.

How does a Z4000 generate it's D.C. offset? If it works like a postwar Lionel transformer, you may not have enough load to generate enough offset to operate the whistle.
Put some sort of load in parallel with your test track.

Also, Lionel used a piece of foam to mount those sound boards. Over time the foam would decay, and allow the underside of the board to come in contact with the metal tender frame, causing the board to short and burn out.
So many boards were damaged this way. If your board is still good, replace the foam with some sort of insulating material. I use a piece of styrene. Some folks use hot glue.

FYI: My SOS board in my Milwaukee Limited diecast steam loco/plastic tender had a whistle which could be activated with a Z1000 or Z4000 whistle button. I did replace the worn foam insulation on the board with two layers of Scotch double-sided tape as per an earlier SOS repair thread!   

Those old SOS boards are kind of hit or miss, but my only SOS engine sounds like it did in 1973 when it was new!  

FYI: My SOS board in my Milwaukee Limited diecast steam loco/plastic tender had a whistle which could be activated with a Z1000 or Z4000 whistle button. I did replace the worn foam insulation on the board with Scotch double-sided tape as per an earlier SOS repair thread!   

Understood.
But, would your Z1000 or Z4000 activate the whistle if only the tender was on the track and nothing else was connected to the transformer? Even in neutral, if the locomotive had a headlight and smoke, they would add to the load on the transformer, as would any lighted cars.

I am not familiar with those two model transformers. Postwar transformers need a certain load to generate the DC offset that operates the whistle.

Thank you, all.

CW, I didn't consider load so I'll put a locomotive on the track with it.  I also have a postwar ZW, so I'll try it with that to eliminate any potential quirk with the Z4000.

The Lionel data sheet shows only how to wire it to the tender truck but zero other info.  There also two potentiometers to adjust something.

No big loss if this doesn't work but I do appreciate all the input.

My 4-4-2 c&o was tethered and died via popped a capacitor.

If there are 2 adjustable pots, the board is a SOS and whistle version. If you are using a postwar ZW, move the whistle control only half-way. If nothing, reverse the wires.

My old 8603 C&O Hudson,MPC, since traded for pre-war AF, had a SOS board that connected to the engine, no whistle.  Many times it would have to run at least 5 minutes before the SOS kicked in.

I finally had some time this morning to look at this.

I connected the circuit board to my old ZW (whistle button works) but all I get for a whistle is some clicks and buzzing.  I swapped the wires around, in sequence, and still get the same results.  For fun I unwrapped the third lead and momentarily touched it to ground and got, what I imagine is, the sound of steam, quite loudly.  Repeating this I can simulate chuffing but not Legacy quality.

So I have a board were SOS works(?) but no whistle.  Any more ideas before I scrap the whole thing?

Thanks

If you have a 6a diode try bridging the rails with it quickly or inserting it inline. (careful, it will get hot fast! Bridging isnt ideal, but should give you a half wave dc for a fast whistle test that a board will see easier. Smaller diodes may work too, but will be even hotter)

Sometimes electronics dont like the old rectifier disks.

The Sound of Steam is just a static sound generator, and the whistle would be integrated, so it sounds like you have found the right wire combo anyhow. If testing with electronics doesn't give a whistle, maybe use it as a auxillary tender behind a PW whistle tender giving you both chuff, whistle and a one-off yet prototypical look.

Lionel had some of these left last I looked, but I lost the part number (Roy Boy had it at one time). It is for running two tenders, slips over the #2s drawbar.

Adriatic, that was it!  A diode in line worked.  Now I have to find out what my friend is using as a transformer.

Thank you.

For permanent use, the diode amps should exceed the transformer amps by a lot (maybe 15amp+ for a ZW) or at very least be more than the maxium amp use of engine, cars, switches, lights, and whistle combined, 6a was a safe bet, 8a would be nicer, some what cooler, good to the 80-90w range.

I have old stuff that won't sound on new transformers, and new that wont sound on old transformers.  You may want to service your transformer whistle switches too. It seems to "sharpen" the signal and response for at least a while if nothing else. If you actually replace the rectifier disk with a big diode you might not have my issues. I just use both, diode on a button and transformer.  I haven't used a large amp post type internally yet to know from experience, other cry eureka.

Reverse the diode and hold for 2-3 seconds and the bell will sound if it has one

Great thread!  And for those following along at home, a TON of MSOS tenders were produced without “whistles”.  (I use that word advisedly... my #6200 turbine sounds like a sick cow).

I’m curious as to what engine this tender was matched to...

Jon

Adriatic Thanks for your help.  I don't have any large diodes in stock so I have to order anyway so I'll go for the 10a.

Jon  This was a great thread because it showed just how helpful the forum is.  I have fixed lots of things over the years but never had an SOS board,  I reached out through the forum and got the answers I needed to make it work.  Thanks everyone.

The tender was paired with a post-war 2065.  It is being used for whistle only.  Someone taped the chuff input lead, since the 2065 has no switch.  When I got it to work, it sounded pretty sick.  Figuring I couldn't make it worse, I played with the two pots on the board and tuned it to sound a little more like a steam whistle.  It is not Legacy or PS2/3 quality, but it is better.

What engine are you using? I have many MPC Sound of Steam Boards in my Parts case, and I have a gentleman who can actually repair the original Electronic Sound of Steam Boards.

Let me know if you still experience issues.

Thanks, Mark.  For the moment, everything is good.

Adriatic posted:

 

Lionel had some of these left last I looked, but I lost the part number (Roy Boy had it at one time). It is for running two tenders, slips over the #2s drawbar.

@Adriatic, The Lionel Part number for the draw bar to knuckle converter you pictured is 610-6655-015. Does not appear to be currently in Lionel's stock. If you have a source, I'd be interested.

Nope, I knew there weren't tons and should have jumped I quess. If you find them and don't buy them out, give me a heads up too. I think it's a very cool piece (though it does make for a huge gap, trimming the bar short and permanent attachment was likely the intention for use.

   I had found mine in the parts drawers of a hobby shop, along with another that had a verticle slot. That one I used on my Marx tin, but it was made of a more brittle plastic and the knuckle snapped off eventually. I really dont think the vertical slot was Lionel, but I doubted the one shown was Lionel for years too.