Diode Conversion For Lionel 1033

awesome tutorial!.....can you provide info on the diode itself? where to get it? what type it is?......thanks for the tips!

Just complete the same upgrade with a 16 amp stud diode.  Found after removing the old rectifier there was insufficient clearance for the stud and nut when attached to the original mounting plate.  My bracket was difficult to bend so I decided to mount the diode parallel to the mount plate using a 2" x 1/2" right angle from the hardware store.  Shortened the side attached to the mounting plate to 1" and the other side to about 3/4", short enough to clear the transformer cover.  Used a machine screw, washer and nut to attach the new bracket to the mounting place with a few drops of thread locker to keep the nut tight.   Hardest part was finding the correct size machine screw in my parts bin.  Replaced the missing resistor wire with a new 10 watt 1.8 ohm resistor.  

Also, the rivet holding the plate was loose so I drilled it out, threaded the bracket hole and secured with a machine screw and washer.  

With the plate removed from the transformer it was much easier to secure all the hardware. 

Unless I missed it, what the diode number?  Diodes depending on part number, are made with either anode or cathode side oriented towards stud side.  For old PW motor whistle, polarity unimportant, but modern locos with electronic whistle and bell, polarity matters.

The favorite recommendations are the 1N1190AR, 1N1186AR, or 1N1184AR diode available from many electronics suppliers. These will retain the stock polarity of the transformer. (Note that for some transformers, this is the reverse of the current conventions set forth post manufacturing - in that case you can opt to use the same numbers without the R to get a diode of the opposite polarity).

rrman posted:

Unless I missed it, what the diode number?  Diodes depending on part number, are made with either anode or cathode side oriented towards stud side.  For old PW motor whistle, polarity unimportant, but modern locos with electronic whistle and bell, polarity matters.

There is no # visible on the diode, purchased from a large Lionel online parts supplier "Justtrains.com" out of Sussex NJ.  They sold two diodes, standard and stud 16 amp (used mainly in the large 2 handle transformer).  This diodes markings indicated the stud is the anode (+) and the solder connection cathode (-).  Therefore is currently wired the reverse of factory.   This transformer was purchased in 1952 and is only used to run post war (1950's) trains.  It could easily be wired to factor spec but that did not seem to matter.  Somewhere along the line the resistor wire was clipped and replace with a piece of hookup wire.  Since they also sold the 1.8 ohm 10 watt resister went with than in place of the resistor wire.  The line cord was brittle so that was also replaced with the correct sized molded plug cord.

Any reason to reverse the polarity to match the factory diagram?

bmoran4 posted:

The favorite recommendations are the 1N1190AR, 1N1186AR, or 1N1184AR diode available from many electronics suppliers. These will retain the stock polarity of the transformer. (Note that for some transformers, this is the reverse of the current conventions set forth post manufacturing - in that case you can opt to use the same numbers without the R to get a diode of the opposite polarity).

There is no # visible on the diode, purchased from a large Lionel online parts supplier "Justtrains.com" out of Sussex NJ.  They sold two diodes, standard and stud 16 amp (used mainly in the large 2 handle transformer).  This diodes markings indicated the stud is the anode (+) and the solder connection cathode (-).  Therefore is currently wired the reverse of factory.   This transformer was purchased in 1952 and is only used to run post war (1950's) trains.  It could easily be wired to factor spec but that did not seem to matter.  Somewhere along the line the resistor wire was clipped and replace with a piece of hookup wire.  Since they also sold the 1.8 ohm 10 watt resister went with than in place of the resistor wire.  The line cord was brittle so that was also replaced with the correct sized molded plug cord.

Any reason to reverse the polarity to match the factory diagram?

@aka1178, the consequences of having reversed polarity of the diode means that the horn/whistle and bell controls will be reversed for newer locomotives. Your 1033's whistle control will activate the bell on such equipped locomotives (instead of the horn/whistle).

You are correct that the pre&postwar locomotives don't have a polarity sensitivity and will whistle/horn regardless of the polarization.

Thanks for the detailed explanation, since it's easy to change I most likely reverse the wiring so it matches the transformer factory wiring diagram.

Since you are using a stud diode, I'm not sure how easily one can "reverse the wiring"... usually one employs a diode of opposite polarity.

If  your 1033 isn't fully integrated and phased with a larger layout in common ground scheme, you can simply reverse your leads to the center and outside rails to effect reverse polarity without rewiring the transformer.

Move the connections (transformer/ resistor) soldered on the bracket to the lug on the diode and the connection from the transformer whistle lug from the diode lug to the bracket.  The bracket is attached to the top insulator plate and isolated from the rest of the transformer.

aka1178 posted:

Thanks for the detailed explanation, since it's easy to change I most likely reverse the wiring so it matches the transformer factory wiring diagram.

Don't do it.

The diagram is actually wrong. Always connect the cathode to the center rail track connection - in the case of the 1033, this would be the "U" terminal - to keep to the convention of the positive offset to the train for whistle, negative for the bell.

Found this service manual for the 1033 transformer, indicates that correctly installed the anode (stud in my case) should go to the whistle post, am I reading it wrong.  I actually still have the original "Instructions for Operating Lionel Multi-control Transformers".  This shows the U post being connected to the outside rail.  Attached both service and operating manual pages

This is where things get messy - The Lionel docs are NOT WRONG! The polarity indicated is as I find most stock transformers. They predate the DC offset polarity convention. It is common to use a stud diode to reverse the polarity of these to bring them into compliance with the DC offset polarity convention, but if the operator was content with he stock polarity and/or wired the transformer into their empire accounting for the stock polarity, why change it? Also, generally followed conventions have the center rail be the variable voltage, and on single throttle transformers such as the 1033, this is the U post.

Take a peek here for Lionel's transformer wiring matrix: http://pictures.olsenstoy.com/cd/transfmr/ps6.pdf

Only change the polarity if you have a reason to do so - if you are content with the operation currently, or can swap the inside and outside leads, I wouldn't necessarily recommend it.

So you don't recommend changing my upgrade connections to match the polarities shown in the service manual? 

Only using to sound the whistle on a 1952 engine 2025 tender (once that's fixed).  The relay needs replacement, some where along the line the relay was energized enough to partially melt the plastic whistle box.  Think the windings are shorted or they were cooked since the electro magnet barely works anymore.

Unless you have a stated need to change the polarity, run with what you have. Postwar locomotives don't care about polarity of the DC offset and will operate their Whistle/Horns with both a + or - offset.

aka1178 posted:

So you don't recommend changing my upgrade connections to match the polarities shown in the service manual?

That's right. You have it wired correctly if it's the opposite of the service diagram. If you are using "U" on the center rail, you can test this by running a newer loco with horn(or whistle) & bell. The 1033 will trigger the horn, not the bell.

Thanks

Thanks

Here is a picture of a diode installed on my 1033 transformer.

I removed the old whistle rectifier and parts, cut off the the old mounting bracket out of the transformer, and soldered in the diode.

Boy, do those whistles blow now and every time!

Quick and easy.

Nice job, wish I had seen this before going with the 16 amp diode.  Your top plate is much better shape than mine which is light brown and really worn,  yours looks almost brand new.     Appears  you also removed the factory circuit breaker, you seem to have an empty space where mine is mounted.

Yardmaster posted:

Here is a picture of a diode installed on my 1033 transformer.

I removed the old whistle rectifier and parts, cut off the the old mounting bracket out of the transformer, and soldered in the diode.

Boy, do those whistles blow now and every time!

Quick and easy.

 

Correct me if I am wrong.  So what you have shown here is another way to do what LIONELTIN showed us in his original post ?  And what do I ask for when buying the diode in you photo ?   Great picture by the way.  

Correct, was not comfortable with the stud clearance I had using the method LIONELTIN showed.  Found the 16 amp diode and 1.8 ohm 10 watt resistor at "Justtrains.com", search "16A-Diode-2".  They also carry the 6 amp diode that you used and the original resistance wire.  Purchased from them since they carried all the parts I needed for the transformer repair and smoke unit upgrade to my 2025 1952 engine.  One stop shopping.

aka1178 posted:

Correct, was not comfortable with the stud clearance I had using the method LIONELTIN showed.  Found the 16 amp diode and 1.8 ohm 10 watt resistor at "Justtrains.com", search "16A-Diode-2".  They also carry the 6 amp diode that you used and the original resistance wire.  Purchased from them since they carried all the parts I needed for the transformer repair and smoke unit upgrade to my 2025 1952 engine.  One stop shopping.

I usually use All Electronics as a source for electronic parts.  I also checked on Evilbay just now.  Nothing found with an amperage of 16.  

Was originally going to the electronics supplier mentioned in an article but found the train parts site that had everything I needed and they did not gouge for shipping.  Might have been a little cheaper but needed other parts, so saved on shipping from multiple suppliers.  Save the name you mentioned for future reference.  I think the 16 amp is primarily used for the older big two handle transformers.  Thanks for the tip.

Yardmaster,

Where did you purchase your diode? And a part number?

Thanks!

JustTrains.com, search  16A-Diode-2   they also carry the 6 amp version and 1.8 ohm 10 watt resistor to replace the original resistance wire (mine was removed).  Here is the direct URL  http://store.justtrains.com/16...le-Diode_p_2682.html

Found them when looking for parts, carry a wide selection of Lionel repair parts and refurbished assemblies.  I also needed a new line cord and liquid smoke conversion kit for my old 1952 2025 steam engine.

Here is the website / part number for the 6 amp diodes. 

      https://www.mouser.com/Product...2bnfkiI4wf3WMw%3D%3D

First, thank you LIONELTIN and YARDMASTER for sharing your technical expertise.

Good morning, Brothers!   I am late to this party, but I hope you still have some interest in this topic, and can point this newbie of sorts in the right direction. I recently opened up a transformer for the first time  to replace the rectifier disc on a beat up 1033. I have all the electronic skill of a History major, so I also bought some "distressed" 1033 transformers to take apart, see how they work, and put them to rights. (You can't damage junk.) I hope now to replace the other discs with diodes, but which way should I skin that cat: 16A-Diode02 or 6A10 - T ?

Is the clearance for the 16A-Diode-2 truly adequate or is it an opportunity for self-inflicted frustration? Opinions differ here. With regard to the 6A10-T, how involved (difficult) is it to remove the old whistle rectifier and parts, and cut off the the old mounting bracket out of the transformer? What cutting tools are needed? (When taking out the appendix I don't want to take out the liver by mistake.)  Is there an observable performance difference using one diode over the other; or using diodes over new rectifier discs?

Your comments would be most welcome. Thanks a lot!

Pete

   I haven't tried yet, but it seems a dremel wheel would be the way to cut the brackets.

   I have wrecked a few post type diodes bending the connections like that. Not many, but it happens. (actually triacs, but very very similar to post diodes).

  I don't have experience with those in this type of application. Ive had good luck with the barrels externally for home spun whistle/bell button boxes.  I like the maneuverability the legs give. 

  The advantage of post type is mostly the heat sink proporties. (it can also be hard to solder to some thick metal frames, the post side deals with that nicely)

  A smaller amp diode will be hotter than a smaller one. I.e., higher amp diodes run cooler than lower amp diodes.

Off topic slightly, consider looking at the thermal breaker while you're in there. (small rectangle, small adjusting stud screw, brass.) If corroded badly or darken from heat swap it....but locate the part first. At least test and adjust it. (I go for just under 4 seconds to a trip with a direct short at full power). Napa may have dropped the 6a auto reset thermal breakers. Last I called I got a rookie that couldn't find them. (I think its 6a... just woke up, allergic to mornings, lol.)

What diode would you use, Butch? I am inclined to go with the 6 amp and leave plenty of room around it for heat dissipation, but I would like to hear from you and others before I butcher the transformer.

You read my mind with the breaker. I bought a Bussmann 6A 12Vbreaker. My understanding is that it is a simple matter of soldering wires to the forks and covering with heat shrink insulation. Correct me if I am wrong, but I believe I can either let it float or hot glue it to the base plate.

Of course I will replace the power cord when I have the 1033 opened up. Since this is my learning 1033, what else should I do to it to secure great performance?

Thanks a lot for your help and generous use of your time!

Pete

Here is a picture of the new circuit breaker installed in a 1033.

I unsoldered the one wire on the old circuit breaker, cut out the old one, hot glued the new one in place and soldered the wires. You have to add a piece of wire from the brekaer up to the B post as shown. This is how the old breaker is wired.

The circuit breaker is a 6 amp Bussmann circuit breaker.

Pete,

I silicone or epoxy items like that. There are usually tabbed case part# or a prefab bracket made.  It's a thermal breaker, cases can get pretty hot. I wouldn't trust hot glue unless it was high temp. 

  I'm a huge fan of good thick rubbery shrink tube. Hated the "shrinkwrap" multi color thin stuff.

  From a pro-look; to wire support at the connection, helping prevent breaking there; to ease of use; to durability, shrink tube is great.

  A 6a diode might work, but I like some overkill when I can manage it. Feed 5a to a 6a diode and you will likely burn yourself a tad touching it.

  I ran a 4a Radio Shack dc supply through a 4a diode and had the solder melt, drip off the leg and loose connection...It puts out 4.4a as it turns out. It would have cooked the diode way early. But the point is how hot an small diode might get. In contrast I can hold a ten amp diode for a few seconds at full power on a 1033 and solder isn't meltng.

  In other words, if whistle happy kids are involved, I'd look to 8a-10a for sure, Both for saftey and to prolong life in less than ideal situations or lack of cooling time. 

  If one fails intermediately, it usually quits when hot and works when cold, so extra amp capabilities are a good thing here imo.

  Bakelight transformer cases won't melt like plastic. The worst case would be a heat spot in the finish long term. I doubt there would be issues with a lager diode especially. 

  Nothing usually suffers running a big amp diode over a small one. The other specs are what are more important. 

  Heat dissapation shouldn't be much of an  issue with the larger diodes. There will be nearly the same amount of heat made total in either size as the voltage drop is about the same, lost as heat. 

  The real difference is the amount of heat that builds in a mass andand surf area for dissipated heat

  E.g., Pour X-btu into both a small mass and a large mass and the large mass has a smaller increase from its static temp. than a small mass that was at the same static temp. Because there is more mass, it requirs more btu to raise a static temp. The more mass the less effect a btu has on top of that.  I.e. it needs more btu to even begin change from static temp.   

  The 1033 average case temp will be the same as before. Only the diode area itself might be hotter.  You can bend the diode legs toward the frame till the body touches it and even get nuts and lay it in white heat sink compound if you wanted to put the heat to the frame where it once was.

   Don't let thoughts of asthetics mess with the form follows function mantra of under the cover electronics; it's not going anywhere even with 1" legs bent to the side.    If you can leave a hook in the hole so it 1 in a million it does get too hot and melted solder, it would be held in place mechanically 

  Heatsink compound on the post type bases wouldn't hurt either.

  The big 8a-10a barrel diodes are not so big as to be a hassle compared to a post. 

  I did like adding a bracket to mount the post type sideways. 

Shell out the extra quarters for one of the bigger diodes.

I agree, Butch. Epoxy or silicone to secure the breaker is more prudent.

Having surplus diode capacity also makes sense. Here is a link to some 10A10 diodes. https://www.amazon.com/20-Piec...=10a+diode&psc=1    Would these suffice?

I always use these stud diodes as they can use the same mounting plate as the rectifier discs originally used. They also handle about 40 amps and thus have a better chance at surviving the inevitable direct short. This was mentioned way above:

bmoran4 posted:

The favorite recommendations are the 1N1190AR, 1N1186AR, or 1N1184AR diode available from many electronics suppliers. These will retain the stock polarity of the transformer. (Note that for some transformers, this is the reverse of the current conventions set forth post manufacturing - in that case you can opt to use the same numbers without the R to get a diode of the opposite polarity).

bmoran4 posted:

I always use these stud diodes as they can use the same mounting plate as the rectifier discs originally used. They also handle about 40 amps and thus have a better chance at surviving the inevitable direct short. This was mentioned way above:

I found a 1033 carcass I had along with a 1N1190AR diode I have on hand. This specific 1N1190AR diode will fit with a little massaging. One would need to use a hacksaw or similar to trim the stud to length and gently bend the terminal to fit.

Not really like that unless your forced to. Thats how you'll wreck some. hc

Firmly hold the upright by needle nose or even side cutters as close as possible to the diide. Don't let it slip as it would pry, pull up, & maybe out. Firm hold, now fold the contact over the tool. You might need another set of pliers; maybe not. A broad curve is best if it is a hard metal (more likely to work harden & snap)

  This tip actually applies to all electronics. Stresses from bending can chip out holes around leg bases, create pressures that are going to compound during heat expanspions. A real hot diode, a crack might fissure more from heat cycling over time and eventually crack like a walnut. From there if the diode is still trying to work you might have flame coming out of the fissure. 

  Stresses continue beyond the surface into the component interior too.  

I never looked into what worked and what didn't for whistles. My supplys are... more like were as Im about run out of everything.... random variety package and salvage parts for the most part.

  Every general purpose diode set Ive used has had the same result. I've not looked at offset deeply enough to know which properties are effective with the relay and boards both. 

   I have two relays that won't work for any diode so far, and two boards that don't respond to disks. Until about a month ago when I found a ten amp that pulls one of the relays. But it's an unmarked salvage part. Until I figure out why, I don't feel comfortable with promotion of any part further than "it's worth a try". Diodes are pretty cheap.

 Exception on what has worked for me ...... a few 4a I played with doubled up, where Id need three or four diode pairs to get enough voltage drop for the offset (too efficient. Some diodes are more efficient and have a lower voltage drop; these were like -0.5v.; we want the normal voltage drop )  (pairing diodes to increase amperage isn't the best way imo. Should one fail for any reason, the other likley becomes immediately overheated.  I started seeing it in some new products. The first, a cooked power supply, two bad diodes paired, one of them cooked (charred like a blackened filet mignon). My hypothesis, one failed by chance, the other cooked; too small alone.

 I always see it as two chances at hosting a "firemans ball" vs one   Those guys make a mess

WoW!!🙈

As a post script to my questions earlier, I have now performed 8 restorations to 1033 transformers with new power cords, diodes, and circuit breakers. All my success is thanks to the kindness and generosity of the above experts who shared their knowledge so freely. Thanks a million, gentlemen!

Two field comments on installing the stud 16V diode: 1.) On my first attempt to make clearance to install the diode I did not support the rectifier mounting plate tab that bends at a right angle beneath the top fiber plate. The result was  a total break in the fiber top plate leaving the rectifier assembly plate totally adrift. The good news is that I was practicing on a junk transformer.  I corrected this mistake the second time with excellent results. Accordingly, please take note that it is essential that you grab the top tab of the rectifier assembly plate with a blunt nose pliers and keep it steady while you use your other hand to bend the bottom of the rectifier assembly plate away from the transformer a bit. This way will avoid a stress fracture of the fiber top plate while giving you plenty of room for the diode.  2.) Lining up the nut and washers to secure the diode through the original rectifier disc assembly hole can be frustrating. I found it very easy to put the nut and large washer on the middle finger of my left hand and line them up behind the hole. Takes a few seconds. Then turn the diode until it bites the nut snugly, and tighten with long nose pliers on the nut and a half inch wrench on the diode. Easy!