G Scale Model Train Forum banner

Pheonix sound problems

  • Pheonix volume up and down problems on 2K2 board

    Votes: 0 0.0%
  • aftermarket sound

    Votes: 0 0.0%
1 - 19 of 19 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
Hi fellow Model Railroad enthusiasts, Im a 30 + years veteran with G Scale but brand new to after market sound systems, I run LGB, Bachmann, Aristocraft trains on 4 tracks plus a trolley with Analog power.

My question is about a used LGB 25552 alco diesel i just purchased, it has a Pheonix 2K2 sound board, works as it should and sounds fantastic except the externeral spdt switch is not controlling the volume up or down, seems like it is stuck in the loudest mode, I did continuity check on switch and its connection to pins 4,5 and 6 and its correctly wired and electrically functioning except its not lowering the volume, as I mentioned seems to be stuck in the loudest mode, can you help with any tips to restore the control function of the switch and how do I disable the sound when not needed, I downloaded the install manual but didn't find much info for this problem, as I said I run a dc set up only. Tnx
 

·
Registered
Joined
·
3,384 Posts
I have a couple older Phoenix and several Sierras. IIRC, the volume control also controls the various functions once you hold it a certain amount of time. On the Sierras you need to "bump it" up/down rather than just holding it to get to the volume you want. I don't recall if the Phoenix is the same, or just the opposite (i.e., hold it for a bit to get volume control).
 

·
Registered
Joined
·
7 Posts
Discussion Starter #4
Thx for your speedy responses, He's what I have done: I tried pulsing the switch and also holding it down and up, but no change, I read that by shorting out pins 4, 5 and 6 to put it into a program mode then remove short and hold spst switch up or down for 1 second will change the startup sounds by 1 volt of track power so as not to have sound turn on from noisy power supplies or to change the start up sound threshold, as far as connections to the sound board, Ive checked continuity with my trusty Simpson 260 all is good. I was hoping for a loose connection or a faulty spst switch or a bad wire... no such luck. There is a small 3 wire phone jack also coming out the side of the loco, I believe it is for programing different sounds but Im brand new to the after market sound, Ive been very happy with the electronic sounds that the engines came with until I heard this pheonix, must admit Im pretty impressed. just way to loud.
 

·
Registered
Joined
·
3,384 Posts
There is a small 3 wire phone jack also coming out the side of the loco, I believe it is for programing different sounds but Im brand new to the after market sound.
Probably, but possibly a charging jack to precharge the battery so the sound continues when the engine stops when run at low speeds.

The 2K2 Handbook does not show an optional charging jack (probably because the operaing voltage is so low), but the Sierra system manuals do.

http://www.phoenixsound.com/pdf/2k2Handbook.pdf
 

·
Registered
Joined
·
7 Posts
Discussion Starter #6
Outcome: I ended up replacing the spdt momentary switch even though it checks out good in the circuit... and the sound works as it should now, push up and hold the sound ramps up in volume, push and hold down and the sound pretty much goes too silent. When I had the replaced switch on the bench I measured it again... one position it was 0 ohms the other position it measured 12 ohms. No doubt this switch went bad, shot the switch with alcohol and cycled it a few times and the resistance went to 0 ohms, I guess dirty contacts, Happy its working, Anyway its time to put this baby back together again, Tnx for all your recommendations it pushed me to look further then what i initially did.

I looked into that jack, it looks like its for programing new sounds and also for setup if you don't like factory supplied sounds and parameters. The manual states that battery gets charged from track power.
 

·
Registered
Joined
·
3,384 Posts
Glad it worked out.

I got a bunch of Chinese switches and they will initially check out OK. But when you solder the wires on, they go bad from the heat unless you get "in and out" very quickly with just the right temp.

Can't tell you how many of these cheap switches I've thrown out.
 

·
Super Modulator
Joined
·
20,525 Posts
I always try to learn something, both from successes and failures.


So, please take this in a constructive manner:


When you checked out the switch the first time, clearly your checkout procedure was flawed. Perhaps you used a continuity meter or function, as opposed to measuring the actual ohms.


You learned a lesson, so next time you will be able to catch the problem the first time, by fixing whatever was flawed in your first "checkout".


Glad you have it working


Greg
 

·
Premium Member
Joined
·
3,884 Posts
The Phoenix jack is for programming the sound unit from a computer via their special adapter and software. And Phoenix does update their sound files and adds new ones from time to time.



The inexpensive ohm meters do not have a good 0 ohm reading due to the limited ranges they have. I have a 55 year old Paco vom that actually places a D cell battery in the low ohm range and can read down to 1/5 of an ohm. And if that is not good enough I have a great unit that has low ohms that needs the leads calabrated to remove their low resistance so I can read less than 1/10 of an ohm.
 

·
Super Modulator
Joined
·
20,525 Posts
Yep, for low ohms, I use either my Fluke meter, or an old cheap analog meter with the zeroing function.... old school, but can read really low ohms.


Greg
 

·
Registered
Joined
·
7 Posts
Discussion Starter #11
Thx gentlemen on your troubleshooting technics, The Simpson 260 while old is still the Cadillac of analog meters if properly used and taken care of. As far as reading 0 ohms its there. when reading components still connected in the circuit depending on the circuit you can get false readings, this is obviously what had happen, shame on me for taking this reading as truth.

To give you analogy when you're doing a forward reverse check on a transistor sometimes you will get away without removing it from the circuit to see if you have a collector to emitter short, sometimes you just can't get that warm fuzzy feeling its good until you remove it from the circuit especially if there's and .3 ohm emitter resister. Same with most components... capacitors you'll get a charge swing but if you're looking for a value, its not going to happen until the component is removed from the circuit, etc etc.

Thank you for your constructive criticism, point well taken and believe me I have lots to learn with these after market sound boards, even after a 40+ year career as an Electrical Engineer designing to component level.

The crazy thing about this is when I opened up the Diesel engine to see what was going on, I was surprised that the original sound board was still intact but electrically cut out of the circuit. I wish I could get a lead on this circuit, it has a serious amplifier as part of the sound circuit, do any of you Veterans have any info on getting schematics on the LGB electronics, I would appreciate that big time.
 

·
Premium Member
Joined
·
3,884 Posts
Original 25552 has a dcc decoder board (LGB on board decoder) which controls lights, motor, smoke AND a susi bus (red connector) that connects via a 4 pin cable to the sound board (the one with super caps).
 

·
Registered
Joined
·
7 Posts
Discussion Starter #14
Dan what you described sounds like what's in there especially with the super caps, do you know if it was just DCC or was it DC also? Next time I crack it open Ill take some definitive pictures. the circuit board is the full length of the top enclosure behind the cab, it has some serious LSI circuits on the board. Greg are you alluding that there are schematics floating around of LGB circuits, that would be fantastic, My experience with this dedicated type electronics is its very preparatory stuff.
 

·
Super Modulator
Joined
·
20,525 Posts
No not many schematics... not implying schematics..



When asking about a board, a picture helps make sure of the model and version... many boards had several versions.


Greg
 

·
Premium Member
Joined
·
3,884 Posts
If you go on the web search for the following to get the parts diagram which also shows the cabling.

LGB 25552 pdf

And you will find the manual (user guide in 3 languages) also which will explain the CV settings for DCC if this unit has DCC which is usually the case if the on board decoder has the red SUSI bus.
 

·
Registered
Joined
·
46 Posts
John mention that he used a Simpson 260 to check the switch. If I remember correctly the Simpson 260 does have low ohms zeroing.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #18
If you go on the web search for the following to get the parts diagram which also shows the cabling.

LGB 25552 pdf

And you will find the manual (user guide in 3 languages) also which will explain the CV settings for DCC if this unit has DCC which is usually the case if the on board decoder has the red SUSI bus.
About a month back or so i scoured the internet for anything I could find on the LGB 25552, I came up with owners manual, Exploded view, Parts diagram, great for a complete tear down but had minimal tech info that I was looking for, I guess i was hoping for a Schematic, Im assuming that if t hey put in an after market sound board the OEM failed, and if it didn't I could retrofit it into another engine.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #19
John mention that he used a Simpson 260 to check the switch. If I remember correctly the Simpson 260 does have low ohms zeroing.
Simpson 206 is an excellent Meter still sold today, the version I own is a series 7, which has Rx1, Rx100 and Rx 10,000 scales, this is my goto meter even before I reach for the Digital Fluke 87V or the 8020A, an Analog Meter will show the trend of a circuit where as a digital will always keep searching for a number to display when looking for the reaction of a circuit.
 
1 - 19 of 19 Posts
Top