Installed Zender diodes on my PW ZW but it still speeds up?

Do the whistles work properly on both handles? If so, I'd suspect they're installed correctly.

Gunrunnerjohn,they work correctly off of both handles.

Thanks
bryan

Well, that would seem to indicate they're installed correctly, at least in my mind. How much speedup do you get, the same as other PW transformers?

Yea john,I get the same as when I originally had it set up with the old ones.

Well, if you have the usual postwar ZW, I'm not at all surprised. In fact, I'd say the ZW is working properly. There is a 5v winding that kicks in when you hit the whistle button. This was provided to compensate for the additional draw imposed by the whistle motor on a steam locomotive. So if you are running a modern efficient can motor, and you use the whistle button to activate the horn, the motor will see the additional 5v and speedup. Does not matter if you have the old Cu rectifier disc or a modern diode; same effect.

Chris
LVHR

Chris, maybe you missed the point that this is a Zener diode, not a conventional diode. The drop across the Zener in one direction is supposed to compensate for the boost due to the extra coil.

Yup, Dale, you got that right! Missed it.

chris
LVHR

So Dale,are you saying that I should not speed up,when I hit the
horn button?

Did you remove the resistor wire that is in parrallel with the rectifier disc now Diode you are using?

The mod recommended with the Zener requires that wire not to be reconnected. G

Sorry to take so long to get back with ya GGG,I will look at that,and I bet that's the problem,the only wire removing I did was when I replaced the wire off the old rectifier disk and attached it to the new diode.

That parallel resistor will screw things up, that's most likely your problem.

Thanks John,now if I could only find out what the parallel resistor looks like,so I can remove it,I will be set.All I see with the top off,is a bunch of black wires.

The resistor looks like a fat wire, most I see are a white braided thing a few inches long. It doesn't look like a resistor. Looks like this.

Bryan, Just a couple post down in another posting is this link for the pictures. G

ZW pics

Thanks George,I will look at it tomorrow and see if i can find anything that looks like it and go from there.I need a location to exactly were the wire is located.I have looked at the Zender installation post,but i really cant tell from it.I will just need to look at that post again,maybe a second time will be a charm.

That lump of white "wire" is the resistor in this photo. You should be able to identify it by the special ends crimped onto the resistance wire, see my photo.

Thanks John,there is a wire like that on both ends of the ZW,so I will take a look a look and see if that is what i need to remove.

Hi Bryon, I somehow got left behind on the posts & someone started a new zener thread. I'm the one that installed the zeners in the original thread. OGR member pa told me about them. I got mine from him. He was 100% correct about how good they work.
If you have a speed change you have the wrong zeners or did something wrong.
What is your zener #?
Now... if.. you have a ZW-R the resistor is the resistor coil looking deal on the side of the whistle control bracket. The R model does not have the long wire. Only the earlier ZW has the white fuzzy resistor wire. There is also resistor wire on the early ones for the bulbs. Don't mix them up!
I have an earlier non R ZW. The resistor wire has a brass terminal spot welded (so to speak) to the bottom corner of the metal recitifer bracket. I grabbed the brass part & wiggled back/forth to crack off the terminal. Taped the end & tucked it out of the way. Tape it good!
Here is a link to the original thread.
http://ogaugerr.infopop.cc/eve...062943327#8062943327
Look it over also.
Very best, Don Johnson

Hi Dale, Did you install your zeners yet?
Very best, Don Johnson

quote:

Only the earlier ZW has the white fuzzy resistor wire.

I believe that that white fuzzy covering is asbestos based. Lionel used it in quite a few places. I always try to minimize disturbing it, and contact with it.

Don,there is a bit of a speed up,on my engine,when I engage the whistle.There is no white wire at all,and I used the exact Zender diode that you listed in your post.I will try to take a picture so maybe you or someone can tell me which wire to detach.

Bryan

Does it do the same thing in both the first and second positions of the horn/whistle switch? If there is a difference, the resistor may still be connected. If the response is the same in both positions, the resistor probably isn't attached to the second switch position - as would be appropriate after the mod.

Yea!!!!!Found the wires,removed them and now it work great.

Hi Bryan. Good going!! You did it. That is big accomplishment to get it all done.
Bryan, how about running all you have with horns & whistles & let us know your experiances with the zeners. List the locos etc. Write a review on what the zeners/sound systems do & don't do. Before & after.
Any photos of what you did would be most helpful to others.
Very best, Don Johnson

quote:

Originally posted by Dale Manquen:
Does it do the same thing in both the first and second positions of the horn/whistle switch? If there is a difference, the resistor may still be connected. If the response is the same in both positions, the resistor probably isn't attached to the second switch position - as would be appropriate after the mod.

Based on the earier discussions I thought the resistor is not required on any position when using a Zener diode. G

I was suggesting a troubleshooting procedure to see if the resistor might still be (improperly) attached.

Will do Don when I get the chance.I played with it just a bit yesterday.I get an intermittent horn when running the train in spots,but it probably has something to do with the track not being clean.

Hi Bryan, I know exactly what you mean. Occasionally mine whitles will give a little toot now & then. Mostly when crossing switches. I've observed this over the last 20 years. Even... when running whistle tenders with a non-whistle transformer. I don't know the true cause. My hunch is the intermittant contact of the rollers can simulate a dc type signal of sorts. Even my new Lionel will do that.
If you think of how the whistle circuit works, it would be unlikely for the transformer to cause this. You'd have to have a short to power in the whistle control circuit. The way the transformer is constructed not likely for that to happen unless your whistle lever sticks to the whistle side. Then it would look biased in the case towards whistle. I bet if that were the case you'd notice it & pull it back to center.
Now & then I clean my track simply by rubbing rail head with scotch brite pad & a wipe with paper towel. No solvents or cleaners ever. I feel any water based track cleaner will in the long run cause pin contact issues.
I have a scotch brite pad on my Lionel track cleaner car & roll up some paper towel for the wiper. It works ok, but truth be told, much faster to just do by hand. My layout is only 6x11 so easy to do.
Very best, Don Johnson

Thanks Don for the advice.And also to you too Dale,you have been a lot of help on other projects that I have.Not much really to say about performance other than what was already posted,the transformer seems to be smoother,I dont know if that is because I havent used it in a good while or something else.Thanks again everyone,and I do mean everyone on this project. Bryan

quote:

Originally posted by superotrackdon:
Now & then I clean my track simply by rubbing rail head with scotch brite pad & a wipe with paper towel. No solvents or cleaners ever. I feel any water based track cleaner will in the long run cause pin contact issues.

FYI, 99% Isopropyl Alcohol has less than 1% water, it's what I use. Works great, and if the dirty rag is any indication, it does take a lot of stuff off.

Hi Bryan, I was specifically refering to the operation of the whistles & horns on modern & postwar trains, before & after the zener installation. The sounding of sounds & speed change of trains. That is exactly what I want to know.
Regarding track cleaning. Good if it works for you.
Very best, Don Johnson

It's been almost a year since this topic was posted and as far as I can tell, 3 people tried installing zener diodes.  Has anyone else tried this and to what effect?

Have had a Zener diode in both a ZW and KW for

more than 15 years. The horn works at any speed

 or not moving and the train does not speed up.

 

What is the part number of the diode you used?

 

I haven't installed anything yet.  I'm fixing up a ZW I bought recently and was intrigued by the posts on this site regarding zener diodes.  Looking over the posts, I found reports from only 3 people who have installed them though.  I was just wondering if in the year or so since the topic was posted anyone else has tried them and what they have to say about it.

I installed one in a LW last night and it works great.  My Williams & MTH (PS-1) horns blow with just a crack of throttle and a push of the whistle button.  (The Lionel steam tenders work good too!)

 

S/F Mike

Thank you.  I ordered a couple from Newark today and will post the results.