Bachmann Online Forum

I received a USRA Spectrum tender for my 4-6-0. I had to reverse the pairs in the tender for proper operation. Interesting.

Rich

Hi Rich
Can you please be more specific about the changes you had to make to the tender, such as wheelset orientation, incorrect wiring, connectors, etc.

Also, did the tender as received cause, or could have caused, any problems such as shorting, stalling, or any heat damage?

The lack of consistency in these tenders could cause someone's locomotive, decoder, or plastic parts to become damaged, especially a newcomer who might not be aware of these variations.

At first I considered the "variants" I mentioned to be only a couple of isolated incidences, but I recently found another tender that was incorrectly wired. Also, as you discovered, the 4 pin adapter connector packed with the tender may not be correctly wired for all applications. 

Thanks

I guess I should have posted the long version.
I recently ordered a Spectrum USRA to run with my 4-6-0 52 inch driver loco. The tender comes with two short jumpers as the tender has the sockets with male pins, different than the small tender that comes with the 4-6-0 52 inch driver loco. The jumpers allow the tender to be connected to the loco. Unfortunately, the jumpers reverse the polarity of each function pair. Therefore it is necessary to reverse the pairs in the tender at the PC board. The loco would run in reverse, the DCC power would be shorted, plus reverse polarity to the headlight. I know, the LED in this case might do nothing as the polarity is reversed. WAG.
The PC board does not have a resistor for the LED headlight. The LED would get 12 volts DC.
Also, when running in reverse, the headlight dims slightly as there is a 120 ohm resistor that routes power from pin 2, reverse light from the decoder. Cut the PC board trace if you do not like the option and program the decoder to leave the light on at all times.
Other than that, the tender seems ok. I plugged in a decoder and all works just fine now with a NCE Power Cab.
The front truck picks up from the right rail (red wire) and the rear truck (red wire) picks up from the left rail. The trucks cannot swivel all the way around.

I believe this tender comes with the 4-6-0 with 63 inch drivers from what I see in the Bachmann photos. The jumpers are not needed and probably do not come with the loco.

(http://i98.photobucket.com/albums/l267/richg1998/Spectrum%204-6-0/ModifiedSpectrumUSRAtender.jpg)

Original tender wiring. Lousy drawing, part hand drawn and part scanned and PC modified.
(http://i98.photobucket.com/albums/l267/richg1998/Spectrum%204-6-0/Spectrum4-6-0originalPCboard.jpg)

I am beginning to see what your mean about the Spectrum tenders. Because of the jumpers, it was necessary to reverse each pair which would be a pain for most modelers. You have to carefully trace and draw out the wiring diagram. I did not post the modified schematic. It could really be confusing.
Notice the two wire and four wire plugs, sockets have pin numbers. Get out your Optivisor.

This I would consider a major over haul.

Rich

Forgot to mention. I actually reversed the two tender pickup wires to match the power coming in from the loco so there would not be a short.
Now the black wire you see in the tender wiring photo is really the right rail, and red the left rail.
Very confusing project. Probably the last time I get any more Spectrum stuff. Much too hard to mix and match.

Rich

Thanks Rich
I thought the compatibility problems were corrected with current release tenders, but apparently only when used with current release locomotives.

I am considering ordering some of these to make special PC boards, for hard wiring decoders or sockets.

http://www.ebyelectro.com/wire_guard/wg_eb725.asp

Download the PDF file, they are ultra micro in size, available with 6, 7, or 8 connectors. A bonus would be the convenience of using test probes.

Another option, slightly larger but fits ok, and allows screw connections on both sides. I trimmed off all the excess nylon to make them more compact.

No telling what release this is. I bought it from The Favorite Spot.

Rich

To All,

I have posted the following many times regarding the 4-6-0 and the "other" tenders. Same problem, slightly different approach but the same solution.

Tender Swap – Bachmann medium Vanderbilt oil tender (Item #89905) with 63" driver 10 wheeler (Item #82307)

Initial test using jumpers provided with the tender – dead short, no operation.

Original plan – move 10 wheeler circuit board into new tender. This proved unworkable for several reasons, 10 wheeler circuit board too large and wires too short to fit into Vanderbilt tender without major modifications to both the tender and the circuit board.

New plan – can existing circuit board from Vanderbilt tender be rewired to work with 10 wheeler. A simple examination of both circuit boards revealed that while different, they both have the same basic connections, so the problem must lie in pin assignments in the connectors.

Tracing wires and a few simple checks revealed that the two wire connector simply brings the loco pickups to the circuit board. Reversing the wires on one end of the two wire jumper corrected this. Now the loco runs but in the wrong direction.

Two of the wires on the four wire plug are the motor leads. Reversing them gave us correct operational direction.

This only left the front headlight. The circuit board in the Vanderbilt tender is for the 2-8-0 which has 12 volt lamps for lighting. The 10 wheeler uses LED's, this is the main reason the circuit board is different. Rather than trying to modify the circuit, I simply replaced the loco headlight LED with a 12 volt lamp.

Additionally I added weight to the Vanderbilt tender bringing it weight to about 5 oz. and replaced all couplers with genuine Kadee #148 on both the loco front and tender.

Result – loco now converted, runs well with original 10 wheeler draw bar and looks great. 

This issue seems to be tied to what tender cam with what loco in the first place. I do not have all of the Bachmann spectrum locos, but from what I have seen, read and experienced, the following may be a good beginning of a compatibility chart:

Light Mountain & Consolidation will work with all of the "medium" tenders.

Heavy Mountain and 2-6-6-2 will work with the long coal tender, hicken tender and long vandy tender

Russian shares same tender with some 10 wheelers, so I am guessing they share the same circuit board.

The 10 wheeler is really a wild card here because it comes with three different tenders, depending on roadname. Some have the low, small "pre 1900" looking tender, some have the small tender from the Russian and one has the same tender as the consolidation, but obviously with a different circuit board.

But again, I think most of these differences are just the pin assignments and the type of headlight.

Sheldon

Additionally,

The 63" driver 4-6-0 did come with the medium USRA tender in one version, Chicago & Northwestern, item #82306, no longer in production. It is likely that tender is wired the same as the other 4-6-0 tenders. The current 63" driver unlettered loco, and the previous NYC loco, have always come with a shorter, but similar tender that is also wired the same as those from the 52" driver versions. It is the same tender as the Russian Decapod.

These wiring changes are needed to put any of the "2-8-0" tenders behind the 4-6-0.

Sheldon

The original USRA long for the USRA light 2-10-2 would NOT work with the USRA heavy 4-802 or the ligcht 2-6-6-2. 
Gene

The medium Vandy tenders that came with my Spectrun 2-8-0s will only work with the factory supplied Bachmann decoders. With a DH123P they are totally dead.

My original plan was to move the boards to my USRA medium tenders, which won't work with any decoder, including Bachmann.

As I mentioned in another thread, Bachmann will replace the 4 Vandys and 3 USRA at a cost of $150, with the caveat that replacements might not be compatible either.

This is irritating to say the least. Perhaps the catalog listings should read DCC "NOT SO READY".   >:(

Again this calls for standardization. They should use the same type of bulbs, same circuit board, same wiring arrangement, NMRA  color wires at all locations in all engines. How hard is that?

Once upon a time all steam locomotives that had power pick up from both loco and tender had standardized pick up and power delivery.  It was possible to mix and match tenders with ease.  Now it takes some effort as the draw bar is attached to the loco for some companies and the tender for others.
Gene

My idea for a "DCC ready" tender is to have a simple light board plugged into a NMRA 8 pin socket. Pull the board, throw it away and plug in any decoder you wish.  How simple is that?

If you get a chance, look at the board in a medium Vandy, way over engineered and probably adds a lot to the initial cost. What a waste!  If someone buys a DCC ready tender, doesn't that suggest the person plans to install a decoder?  "Here's Your Sign".

I agree with Paul, all decoders come wired with the standard color code, why not the tenders and locomotives?  I'm not looking forward to hardwiring my 7 tenders, but that's what I will do.  Then I will give the boards to my wife for target practice.

Some of that engineering involves noise suppression for Europe. But even that could be standardized into a smaller package.

Next we should require Ford, GM, Toyota and Honda to use the same parts and designs to build their cars.

NOT!, and not likely. I agree it would have been better if Bachmann had thought their design through and than stayed with one universal tender wiring scheme. But we are where we are, just like the wheels on my Ford will not fit a Chevy.

Capitalist competition, although chaotic, wasteful and redundent at times, has brought about way more advancement and inovation than forced standardization ever will.

It is easy to use hindsight to suggest what should have been done. Much harder to open your bank account, design a product, bring it to market and make a profit.

Personally, I'm just thrilled with all this great stuff we have to choose from.

As for installing DCC in these locos, I don't understand why most of you don't just ditch all the old wiring and hard wire your chosen decoder? That is definately not harder than all this circuit board modification before plugging in the decoder?

Me, I don't need decoders, my trains run just fine on DC.

Sheldon

The very best tender to loco drawbar was the one first used on the P2K 0-8-0 switcher.  It acted as both drawbar and electrical connection and provided a scale distance between engine and tender.

No other tender drawbar cames close.  Period.

I'd pay a little extra just to have this drawbar fitted to all steam tender locos.

Roger T.- You're dead on!  I just bought a used switcher, and it has what I would definitely call the best connection I have ever seen/used. And it is very easy to connect and disconnect... with a positive latch and an easy-press-to-release botton. Wouldn't it be nice if more engines had the same!?!- Mike