How Necessary is the PC board in an HHP-8?

[CAB_IV]

Hello!

I was told that the PC-board on the HHP8 actually slows it down and that most bachmann engines perform better when directly wired to a decoder. (at the very least, they go faster. the HHP-8 is almost laughably slow compared to the AEM7s from atlas,  and even the AEM7 only reaches 125 scale MPH.  Realistically, i'd like to make the speeds comparable if possible).

The reason i want to do this is to get some extra performance out of my engine.   I have a club open house coming up, and i wanted to run a long distance amtrak train (Baggage-dorm/lounge-2 viewliners-diner-amfleet cafe/5 coaches.   the club's westbound mainline has a long 4% grade, so this is a tough spot.   I've already made one test attempt with the HHP-8 with bullfrog snot (increases traction) applied to one wheel set, and it wasn't quite able to pull far up the hill, and couldn't really handle the full train even on level track.   

My only other option is a pair of AEM7s or an American GK E60MA Kitbash (this burte can actually pull the whole train by itself no problem when it works, lol), but i wanted to go for the attractive streamlined engine first. besides, i've hardly run the HHP8, and i've had it for years, lol.

this is a photo of the train i'm going for.

[Jim Banner]

Isn't the maximum speed of the HPP-8 only 125 mph?  Curiosity makes me ask what speed yours does and how you measured it.

Removing the pcb may increase speed slightly, depending on the lighting circuit used.  Why not hard wire in a decoder and see?  Then speed match the locomotives.  Do your decoders support speed tables or were you planning a three point match?

Jim

[CAB_IV]

Isn't the maximum speed of the HPP-8 only 125 mph?  Curiosity makes me ask what speed yours does and how you measured it.

Didn't do any quantative analysis, just observation.  I do know the Atlas AEM7 does have a top speed of just around 125 scale miles per hour.  This was measured by Model Railroader Magazine, and i can't see why they'd be wrong/lie. 

Either way, these HHP8s were moving fairly slow.  slow enough that i don't think it will be able to pace well with the other trains on the layout.  Don't get me wrong, they move, but they don't capture the prototypical essence of these locomotives when you have them full throttle unless they are not pulling anything.

Removing the pcb may increase speed slightly, depending on the lighting circuit used.  Why not hard wire in a decoder and see?  Then speed match the locomotives.  Do your decoders support speed tables or were you planning a three point match?

Jim

I didn't want to do any serious cutting before i got all the facts. there are quite a bit of resistors on that PC Board, and the last thing i want to do is blow out my headlights/markers.

I intend to use a TCS M-series decoder in there, and i did test it with an MC2 from one of my AEM7s. I could try changing the speed tables (i've rarely done this), and see how it does.   

Still looking for a Horspower increase, if that can be obtained.

[Jim Banner]

Didn't do any quantative analysis, just observation.  I do know the Atlas AEM7 does have a top speed of just around 125 scale miles per hour.  This was measured by Model Railroader Magazine, and i can't see why they'd be wrong/lie.

I don't think MR would lie about it, but unless you are using the same command station with the same power supply and the same voltage coming out of your outlets, your results and my results and MR's results are all likely to be different.  The actual top speed depends on track voltage which can vary from as low as 12 volt rms to as high as 18 volts rms, depending on the command station and what it powering it.  Even on the same track, two apparently identical locomotives can have different top speeds because of mechanical factors, usually related to drag due to component fit, finish, and state of lubrication.  If you have had your HPP-8 for years and have run it very little, it may need lubrication and breaking in before it will reach its maximum speed.

The differences in speed seem to be worse at higher speeds.  A pair of "identical" locomotives that work together perfectly on a drag freight at 25 mph may fight one another on a passenger train at 80.  I can only guess that the problem gets even more pronounced at 125 mph as nothing went that fast in the era I model.  I think you will be much happier with a speed table match between your locomotives than you would be with a three point match because you can force your locomotives to match throughout that high speed range.

Jim

[CAB_IV]

  Even on the same track, two apparently identical locomotives can have different top speeds because of mechanical factors, usually related to drag due to component fit, finish, and state of lubrication.  If you have had your HPP-8 for years and have run it very little, it may need lubrication and breaking in before it will reach its maximum speed.

this may be true, THis would be the first time its recieved any kind of major use, but its still lacking the power i need.    While i wasn't looking for them to be perfectly matched, I was hoping i could get a more legitimate rate of speed out of the models.   Its possible that the gearing and motors prevents this, but i'm told that when the circuit board is removed, that things run faster/stronger. 

I haven't had to much trouble getting the AEM7s to run at top speed with eachother, but i figured an HHP-8 is a more appropriate locomotive for the long distance electric trains.

[mlrr]

Hello!

I was told that the PC-board on the HHP8 actually slows it down and that most bachmann engines perform better when directly wired to a decoder. (at the very least, they go faster. the HHP-8 is almost laughably slow compared to the AEM7s from atlas,  and even the AEM7 only reaches 125 scale MPH.  Realistically, i'd like to make the speeds comparable if possible).

The reason i want to do this is to get some extra performance out of my engine.   I have a club open house coming up, and i wanted to run a long distance amtrak train (Baggage-dorm/lounge-2 viewliners-diner-amfleet cafe/5 coaches.   the club's westbound mainline has a long 4% grade, so this is a tough spot.   I've already made one test attempt with the HHP-8 with bullfrog snot (increases traction) applied to one wheel set, and it wasn't quite able to pull far up the hill, and couldn't really handle the full train even on level track.   

My only other option is a pair of AEM7s or an American GK E60MA Kitbash (this burte can actually pull the whole train by itself no problem when it works, lol), but i wanted to go for the attractive streamlined engine first. besides, i've hardly run the HHP8, and i've had it for years, lol.

this is a photo of the train i'm going for.

Thanks for posting!  I've been bothered by this as well!  I can attest to the fact that the AEM7 on a NCE Powerhouse Pro system does reach a top speed of 125 scale MPH with TCS drop-in decoders.  I have a trainspeed speedometer installed on my layout.  This past weekend, the throttle wasn't even near 110/126 on my NCE cab and engine number 907 was doing 125 scale MPH pulling 5 cars (three cars short of a prototypical Northeast Regional). 

On the other hand, my Bachmann HHP (equipped with a DH123 decoder) with no load, was flirting with around 100 MPH (just barely) at a setting of 126/126 on the same system.  If hard-wiring the decoder will help that would be great!  The only thing holding me up currently is the prospect of installing a QSI sound decoder.  As soon as the sound sets become available for these locos, they're going right in.  If it needs to be hard-wired, so be it.

Thanks again for starting this thread!  Has anyone noticed this issue with the Acela power cars too?  I still run them on DC because I'm afraid they'll perform like the HHPs under dcc.

[CAB_IV]

My Acela set has a TCS DP5X in the powered car, and it seems to run reasonably.  It would probably help to have a pair of power cars (can't find my other powered chassis, but when i do, i'm going to try double heading).   

At least on the club layout, the only issues come from not having enough power to maintain speeds on certain grades, but thats not at all surprising considering the weight of the train and the hills involved.

I will say that the Acela cars themselves (as well as the dummy locomotive) probably need to have their trucks lubricated at the very least.   they are not very free rolling, and this is probably what holds them up (you know its bad because every acela set i've seen has a characteristic wheel "squeal" when you roll it.)

I haven't messed with that HHP8 in a while (it turns out the intended train was having extreme derailment issues which pretty much forced me to remove it.  I've been running a SEPTA set with Walthers cars and an Atlas AEM7 instead).   When i get some time, i'll play with it some more.

[mlrr]

The wheels definitely need to be lubricated.  Lube the wheel bearings and the wheel wipe contacts.  The squeal is mostly from the contact between the copper pick-up and the inside of the wheels.  I lubed these spots Monday.  It seems that this needs to be done fairly often.

When you say the train runs reasonably, I assume it tops out near or close to 150 MPH under DCC?

Members on other forums support your earlier claim that removing the PC board and hard-wiring improves performance.  I have yet to try this myself but the confirmation eases my mind a bit.

One thing I want to point out is that the HHPs on DC power started up and slowed down smoothly in addition to getting up to 125 MPH scale speed.  The Acelas that I have don't start up smoothly on DC control.  Lubing the cars helps a LITTLE bit.

[CAB_IV]

The wheels definitely need to be lubricated.  Lube the wheel bearings and the wheel wipe contacts.  The squeal is mostly from the contact between the copper pick-up and the inside of the wheels.  I lubed these spots Monday.  It seems that this needs to be done fairly often.

When you say the train runs reasonably, I assume it tops out near or close to 150 MPH under DCC?

Members on other forums support your earlier claim that removing the PC board and hard-wiring improves performance.  I have yet to try this myself but the confirmation eases my mind a bit.

One thing I want to point out is that the HHPs on DC power started up and slowed down smoothly in addition to getting up to 125 MPH scale speed.  The Acelas that I have don't start up smoothly on DC control.  Lubing the cars helps a LITTLE bit.

Nah, its not going that fast, but i haven't lubed all the coach wheels yet either,  only the dummy end (I can't find my other powered end for the life of me!).   However, it moves fast enough that i don't feel like i'm moving slower than a passenger train should.   my HHP8 could not catch up to the Acela set, but i'm still sure my AEM7s can out run it.

If it is true what you say, that others support my plans, i'll have to get a decoder for it.  the only reason i haven't is that its not on my decoder priority list, so to speak.

[mlrr]

The latest HHPs with DCC on-board don't seem to have this problem (651, 656, 663).  I test-ran it yesterday (running light) and it made it over 125 MPH.  The initial run (650, 655, 664) of the HHPs did not make it up to that speed under the same conditions.

I'm trying to find a post on a forum where someone recommended getting rid of a capacitor on the PCB board and that may solve the slow seed problem.

Just to note (I'm not sure if this was an isolated incident): My HHP motor clicked and slow speeds for a while.  I think it had something to do with the wound can motor and I had to take it apart.  It seems that by taking the motor out of the chassis and letting it run on its own for a little while eliminated that problem.  The problem must've been caused by excess residue in the motor.  It runs fine now!

[Doneldon]

Even on a very large club layout a train going a scale 125 mph is going to make the circuit in a pretty short time, like a couple of minutes, max, and it might make the other trains look silly.

Also, if this is a long-distance train you might need some sleepers in the consist.

[CAB_IV]

The latest HHPs with DCC on-board don't seem to have this problem (651, 656, 663).  I test-ran it yesterday (running light) and it made it over 125 MPH.  The initial run (650, 655, 664) of the HHPs did not make it up to that speed under the same conditions.

I'm trying to find a post on a forum where someone recommended getting rid of a capacitor on the PCB board and that may solve the slow seed problem.

Yeah, i haven't ever gotten back to this engine.  I hope to in the future, but we'll see. i'm just nervous that i won't have the right resistors if i hook up any old decoder to the model.

[CAB_IV]

Even on a very large club layout a train going a scale 125 mph is going to make the circuit in a pretty short time, like a couple of minutes, max, and it might make the other trains look silly.

We still have a signal system we have to follow.  Besides,  during show season, "the REALLY FAST train tends to get more oohs and ahhs than the super detailed one i just left in the dust.   as long as i don't tail-gate i'm fine.   besides,   these trains are great for our "junior engineers",  since when we let the kids run, i can go through more kids faster (tickets are for two laps,   and some slow freight drag takes FOREVER to get around). 

Also, if this is a long-distance train you might need some sleepers in the consist.

Yes, those angular cars mid-way in the train are called Viewliners, and they are Amtrak's new sleepers

[mlrr]

I took the shell off both number 651 and 655 this weekend to inspect the circuit board.  I can't determine any differences aside from the the different sized component parts used.  I have no idea how to read the values of these components but they all seem to be in the same relative positions with respect to one another.  I wonder how much these new pc boards for the new HHPs cost.  It would be interesting to see if that is where the problem resides (that seems to be the case according to others).

[mlrr]

**Update**

The problem with the HHPs speed (650, 655 and 664) is in fact the PC Board.  The newer run (651, 656 and 663) have an optomized circuit board which explains why my 651 runs much better.  Unfortunately, Bachmann's price tag for the optomized PCB is $40/each.  I would've though $20 tops but that's another story.

I have a solution and it's been proven on two of the three HHPs I have from the first run (650 and 664). 

I was reluctant to hardwire the entire decoder to the locomotive especially since the circuit board already has the appropriate resistors for the LEDs.

The solution (and I wish I thought of this sooner, it just never occurred to me even when people were saying "hardwire hardwire hardwire").  You can still maintain use of the circuit board.  Just bypass the PCB with the motor leads.  The orange wire on the decoder harness should be spliced and connected to the red wire (M+) motor lead and the gray wire from the decoder harness to the black wire motor lead (M-).

The process takes less than 20 minutes.

By doing this, the current from the decoder to the motor does not have to run through the PCB on the HHP.  My locos now get up to 128 scale MPH (with no load).  I was lucky if they'd reached 100 MPH before.

Hope this helps everyone else who is curious about this and have noticed this before.