Hey folks
i picked up a Tech 7 Ampac 760 from eBay as my first power pack. The throttle goes allll the way round and round, which seems wrong to me, but like I said, first power pack. Should I be returning this?
Honestly, I do not know as I do not have this powerpack. However, I have at least 5 MRC powerpacks. All of them have a limit when you turn the handle (maybe 300 degrees?). Perhaps yours is faulty. I would check with MRC quickly, then return it.
MRC does not say in the Tech 7 Amoac 760 manual whether it uses a pot or an encoder for the speed control. But every MRC throttle I have ever seen has stops at the minimum and maximum positions.
The manual indicates if the unit is in warranty you can send it back with $15 to cover shipping and handling. You would need proof of original purchse, which I doubt you’d get from an eBay sale. My advice is that you try them using the contact information in the manual:
(732) 225-6360
Model Rectifier Corporation, Parts & Service, 80 Newfield Avenue, Edison, NJ 08837-3817
I have one. The throttle does not go all the way around. It has two stops, one at off and one at full throttle. Yours is defective.
These are very good units. The momentum and brake features are excellent and so is the power delivery. Lots of spare capacity to run several locomotives in a consist.
Yes.
The throttle should sweep about 270 degrees with positive stops at both ends of rotation.
-Kevin
Far more than 270 degrees. More like 300 degrees or perhaps more as noted by another poster.
You should try to be more accurate when posting specific information. Especially when you don’t have an MRC 760 to look at, although the MRC photo of their own unit is pretty clear.
Mike
Completely uncalled for attack on another poster. I said 300 degrees as a guess, I did not put a protractor on any of my MRC powerpacks. Kevin said @270. You know what? We’ve already decided that the powerpack was broken - it should stop (270, 285, 300 or whatever degrees). The OP should return it and get his money back. Everyone has agreed to this. Your post was pretty much an attack on Kevin (again). Please stop doing this. Kevin has always given helpful info in his posts.
Just posting the correct information. No criticism was made nor intended. I’m really not sure what the points of these other posts were after I confirmed the actual facts.
Looking again I’d say the range of the throttle knob is closer to 330 degrees.
The key point is not the actual range but that there are two stops. That was something I confirmed from looking at my actual unit I use regularly.
“About 270 degrees” is not specific information.
From MRC:
Key Features:
- Accutec Technology™ provides smoother performance and helps maintain the extra power when climbing grades or running over poor track conditions
- Proportional Tracking Control an innovative system of control that yields the most responsive, realistic model train operation
- Automatic Circuit Protector automatically disconnects power to the track to protect your equipment if overload occurs
- Main Line Direction Switch throw the switch to reverse direction of the loco
- More Powerful than others in its class with power to pull heavy loads and operate accessories
- Pilot Indicator Light shows power is being delivered to the track
Yes, completely uncalled for, but it is what Mike does. At least he did not personally insult me this time.
It is all he does, it is his only act, and the only ability he likes to show off. He certainly does not like to show off his model trains. This is a model train forum, remember?
As long as the moderators continue to allow it, we will need to put up with it.
I apologize to all for my estimation being off by 10% and all the confusion that must have caused.
[*-)]
I like showing off my model trains. Maybe someday Mike will do the same, and he can drop this tiresome dispute-baiting and enjoy himself.
-Photograph by Kevin Parson
I guess I should have said “About 3/4 of a turn” instead of using the degrees to equal 75% of a full rotation. I can see how that could confuse some people that have a hard time visualizing “Knob Spin Increments”, or KSI factors.
[(-D]
Anyway, on my layout, 300 degrees (give or take a few) is still about 3/4 of a turn. I think my response to the OP was OK to answer his question.
- - - - - - - - - -
If nothing else, I did get a couple new additional screen-shots for my ever-growing “Things Mike Has Actually Posted” file before he goes back and edits them all for content. Maybe someday I will compile it all into a yearbook or something.
-Kevin
Uh huh.
That’s what always happens on the forum. You do it, I do it, we all do it. If the thread should have ended with your first post, then why add another post of your own?
You should have stopped when you were ahead. Now, you are off 30 degrees the other way.
[quote user=“gmpullman”]
Billwiz
All of them have a limit when you turn the handle (maybe 300 degrees?).
From MRC:
Key Features:
- Accutec Technology™ provides smoother performance and helps maintain the extra power when climbing grades or running over poor track conditions
- Proportional Tracking Control an innovative system of control that yields the most responsive, realistic model train operation
- Automatic Circuit Protector automatically disconnects power to the track to protect your equipment if overload occurs
- Main Line Direction Switch throw the switch to reverse direction of the loco
- More Powerful than others in its class with power to pull heavy loads and operate accessories
In the interest of salvaging a tiny shred of meaningfulness from this train wreck:
Billwiz, if you are at all handy, some of these potentiometer-based controls don’t have the stops built mechanically into the actual pot, but use external plastic stubs that bear on something, perhaps in the plastic handle.
If you’re comfortable with a little disassembly, and you can’t or don’t want to get your money back (or a partial refund from ) your seller – both of which you have a strong claim on, if he implied or sold you the pack as serviceable – you can take the knob off or look at the pot inside to identify what is broken to let the knob go around and around.
Depending on how the potentiometer is made internally, it might work just fine electrically without ‘shorting’ in the non-scale 60 degrees of rotation, in which case you could make a stop glued to the knob with a couple of blocks or posts glued to the case to arrest rotation, and gin up some appropriate friction arrangement to hold the knob in intermediate position if its action is loose or floppy.
You could of course easily remove and replace the pot with something compatible – use a multimeter to determine resistance at zero and full, and get something electrically compatible from a source like Mouser. You’d need to know or learn electrical soldering, but that is a valuable modeling skill in its own right.
As I recall, the MRC case screws are a ‘security’ type, either Allen hexes or Torx-style with a pin in the center. Any of the eBay or Harbor Freight ‘security bit’ sets for replaceable-bit screwdrivers will contain the appropriate bit to get these out.
Here is a look at the outside of the Tech 7 Ampac 760.
Are you sure the throttle knob is pushed on all the way? Not sure how they are mounted but the rotating handle on the control knob is the visual indicator of the throttle position and so may have the stops moulded in somehow, underneath the control knob.