How do I revert back from DCC to Analog on an LGB F7 loco?

S

SuperDave

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Hello,
I recently purchased an LGB F7 A-B loco set online.
The locos are in mint condition.
I already have a few LGB A-B sets in various road names and I am familiar with them and the way that they work.
I placed them on my track and hooked up the 2 cables between the A and B unit so that the sound will work through both the A and B units.
I made sure that the switches on the back of each unit were set correctly for A-B operation.
I turned the power on and the locos moved okay but the A unit did not have any lights or sound in either direction.
The light in the engineers cab and the marker lights should be on all the time in either direction while the main headlight should be on when the Loco is moving forward and then it turns off when reversing.
The sound from the B unit was just fine. I checked the cable connections and even swapped them out for another set - there was no difference.
I contacted the seller and he said that his layout is all digital and that they were working just fine on his layout.
I am just old school with a regular analog transformer.
My question is, how do I revert the A unit back to Analog so that the lights and sound will work on my layout?
All my LGB locos are Analog so I am not very familiar with DCC operations.
Any help would be appreciated.
Thank you,
David
 
Hi David,

Sounds like some decoder CVs (Configuration Variables) were changed in the loco by the previous owner(s). I believe you will need to find someone with a digital system that can reset the decoder to the factory default values. Instructions are in the manual. The manual is available on-line if you don't have the original. That should take care of the problems you are seeing.

A second possibility is that wire harness(s) somehow got unplugged from the decoder. You'll need to take the body off the loco to check this.

If neither of these solutions solve your issue, then there are other problems that should probably have been pointed out by the seller.

By the way, unless the prior owner had a Märklin or ESU mfx system you can be almost certain some decoder CVs were changed as it is very unlikely he was using the default loco address of 3 on his DCC system. It could be he tried to reset the decoder before selling it on and messed it up.
 
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Under normal circumstances a DCC equipped loco should run just fine with an Analogue controller but not a fancy electronic gizmo one. An LGB one should give no problems, but others may be fine I just have no experience with other than LGB but do know of the pitfalls with some controller types. As stated sounds like some of the cv’s have been messed around with. If the chip is reverted to factory settings things ought to be fine.
 
Thank you both very much for your responses! Is there a particular type of digital controller that I would need to look for? Does it have to be one from LGB?
 
SuperDave said:
Thank you both very much for your responses! Is there a particular type of digital controller that I would need to look for? Does it have to be one from LGB?
Click to expand...
That is a big question, do you want a DCC system to run the loco or just to update the Cv’s? I use a small Z21 system to update Cv’s but it would not be suitable to run anything much bigger than a Stainz. I would look round for a local modeler or club that could help you update your loco if you wish to stay Analogue. No doubt someone will chip in with a suggestion of a DCC system to run with, I personally use a Massoth system but be warned good sized DCC systems for big locomotives do not come cheep.
 
I don't think that I will go Digital - it's hard to teach an old dog new tricks! : )
All my locos are just analog and I'm happy with that.
I was just thinking that if I could find someone, like you have suggested, to check it out for me
and hopefully get it back to factory specs. Unfortunately with all this Flu-19 stuff, there aren't any
train shows to go to so I'll have to contact some local Train stores, of which there are very few these days unfortunately!
I really appreciate all your quick responses and suggestions!
 
I know Canada is BIG, but we have a few Users who are in that area.. ;)

One of them may be able to suggest someone close to you?


Beware of 'just' factory defaulting the decoder. - This could set the light outputs to full track voltage, and blow the bulbs.
We also do not know what make of decoder is fitted? - This may mean that any CV values we suggest (if we assume the make) could be incorrect.

Either a Supplier, or someone with a little knowledge, should be able to help you.

Dependent how old the units are, there were different arrangements for cabling between the units for pure analogue, and DCC sets. - If a third-party decoder has been installed, even these conventions may not apply?

PhilP.
 
LOL! There might be a few around! ; )
It all seems very complicated, I think that I will leave it to someone who knows what they are doing!
Thank you Philip and have a Happy Thanksgiving! As we say up here, "Gobble 'til you Wobble!" : )
 
SuperDave said:
Thank you Philip and have a Happy Thanksgiving! As we say up here, "Gobble 'til you Wobble!" : )
Click to expand...
What is this Thanksgiving malarkey ;)
 
Sorry Gentlemen, I assumed that you were from the States! ; )
I'm just new to this whole Forum stuff!
Kindest regards, eh!
 
David,
Does the A unit, on it's own:
Move?
Have lights?
Have sound?

Can the Seller confirm that the A unit has a speaker in it? - Or can you see a speaker? Possibly through a series of holes on the underside of the loco?

(Just a stream of thoughts..)

PhilP.
 
Greg Elmassian said:
That was the reason for my question, in the first post, the OP states the lights do not come on. ( 7th line of his post)

Greg
Click to expand...
I read it that they do on the B unit, though? - Inferred, not stated, and I can't remember if the B unit has internal (or external) lights.

Phil.
 
Hello,
Yes I did try it at full throttle in both directions and none of the lights come on.
In LGB F7 locos, the sound unit is actually in the B unit and the 2 cables that connect the A and B units together
allow the sound to come through on both the speaker in the B unit and the one in the A unit.
The A unit alone doesn't have a sound unit in it, just a speaker. The lights should work on the A unit whether the B unit
is attached or not. Hope this clarifies things.
 
The A unit on it's own moves fine in both directions, just no lights. When hooked up to the B unit and the cables attached, there is only sound in the B unit but not the A.
 
Sounds like 2 separate issues... the speaker issue should be easy to trace... perhaps verify that the speaker wires in the A unit indeed go to the plug/socket you are using .... you could also verify that the B unit speaker plug is "hot" with a small speaker, and touch it's wires to the B unit's plug.

I don't know the connectors and the pinout myself. A wiring diagram if someone has it would help.

Greg
 
Hi Greg,
Thank you for your suggestions.
I tested the B unit with different cables and even hooked it up to one of my existing LGB F7 locos - The B unit works fine and provides sound to my other F7 A unit.
I believe that the issue all stems from the F7 A unit and the digital decoder.
 
Dave remind me.. - I am being lazy / have other things to do. Washing up! :(

Am i right in thinking the A unit has the motor's, but the B unit does not? - I am thinking the decoder is not OEM equipment, perhaps?
It may be 'whoever' fitted the decoder, disconnected all except what was needed, from the connectors?

From memory, these units a re pretty easy to tear-down? - Like Greg say's, I think there may be a wiring issue for the speaker?
Then it may be a simple configuration issue for the lights?

PhilP.
 
Hello Philip,
Yes, you are correct. The A unit has the 2 motors and the B unit has the sound system.
I will ask my son to disassemble the A unit shell for me - my eyes are not the greatest anymore! : (
Would you happen to have a link to an exploded parts list or take-apart video for the LGB F7 loco?
 
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