NT-2701 - various issues

[nipsmg]

I just picked up a Rush the Rock with various issues:

-Starts off so dim it’s unreadable then warms up to be viewable but dim.
-Picture is too wide
-(WTF?! ) Anode cup MISSING on anode wire!

So, I’m obviously replacing the fly back because of the anode cup.
I’m going to get a cap kit.  I’ll pull the monitor today or tomorrow and find out if it’s Full Family or Li Chin.

Also, since I want to keep this machine alive as long as possible, are there any consumer tubes that can be swapped into this chassis? (Are the tubes different for a med res chassis?!)

Any other suggestions/things to do?  I have no experience with this type of chassis so I’m happy to take any advice I can get.

Thanks!

[MKFan4Life]

I'd definitely put in a new flyback, and if you have no idea when it was recapped, do a new cap kit to it.  Emissions from the tube itself could be low, so that might explain the dim display, but you'll be able to tell easier when the flyback and caps are in. If you know someone with a tube rejuvenator, they could look at the output of your 3 guns in the tube and rejuve it if needed.

I have an NT-2701 Medium Resolution in my Gauntlet Legends cabinet. I have recapped it, installed a flyback, and TWICE had to replace this bipolar capacitor on the small pincushion board, because it gets really hot and goes out (causing pincushion problems). Install a good quality BP cap rated for 105 degrees there for better longevity. Mine's had a really good display (knock on wood) since I did that work several years back. I will say, if you recap, pay EXTRA ATTENTION to the capacitor polarity, as I have found at least 3 times Neotec has incorrectly screen printed the pcb showing the polarity REVERSED on the board. So just look at the capacitor you remove and put the new one back just like that, if the chassis worked before, and you'll be golden.

For the width problem, try adjusting the Horizontal Width Pot (can't remember if it's on the remote board or main pcb). And, if that doesn't work, CAREFULLY with a plastic width coil tool, adjust the Horizontal Width Coil.

From what I have read, a tube's resolution is dependent on the chassis itself. But you must have a yoke (containing the vertical and horizontal deflection coils) that is compatible with your chassis. Most people doing tube swaps use a multimeter to take resistance readings (in Ohms) of each of the coils. The larger reading is your vertical coil. And then they try their best to match a donor tube that has very close readings to the original. (I think +/- 10% difference is acceptable) Some say to have an actual inductance measurement to go by, in Henries, which require an LCR meter. I've done a swap from a TV just using resistance, and it's been running fine for a few years in my MAME cabinet.

Here's a good link where someone restored a pair of Rush cabs, and it has a LOT of monitor info, as well as tons of other stuff: http://www.pinrepair.com/rush/

Here's a link about tube swaps (but there are many more around the net!): https://arcademonitor.com/Arcade-Monitor-Repair/swapping_arcade_monitor_picture_tube.php

 

[nipsmg]

I've done a tube swap on a standard res chassis, but given this is a med res chassis, does it require a different type of tube?  If not, I've not seen any compatibility lists for confirmed tube swaps on NT-2701 chassis before.  If you know of any please let me know.

I got a cap kit (including the bipolars) from arcadepartsandrepair.com.  I've used their cap kit before on a K7000 and the parts are all legit nichicon caps, high quality, no knockoff crap.

I also bought a HOT and the flyback, they're on the way.  I'm hoping I don't have to rejuve the tube because I know nobody with a rejuivnator but hopefully I can find someone locally if I have to. 

The game is funcitonal (kind-of) but says steering is not detected at start-up.  Lots of posts have pointed to a bad steering pot (even it it works in game), so I have that on order as well.

Active steering wasn't working at all, so I dropped the steering wheel and found that someone had "repaired" the existing steering belt with electrical tape, and it was completely off the gears.  All of the gears look intact, and I can see the motor engage and turn both directions at startup, and it runs when I hit abort in the calibration test menu... The (newer/better material) belt is on the way from Grainger, and I'm hopeful that installing/tensioning it correctly will get me Active Steering / Force Feedback.  I've also heard the 2 OPA541AP's (Q1/Q2) on the active steering board cause all kinds of issues if/when they go, so if it's not behaving I'll swap those out as well, I have 2 on order from TI.

The brake pedal is always registering some value even when not depressed, and the gas pedal is "jumpy" in the calibration menu, so I've got to replace those pots as well, all on order.

By the time I'm done I'll have replaced 3/4 of the parts in this machine, but I'm hopeful it'll be back to working order soon.


Thanks for your help/info.

[MKFan4Life]

I have always heard that as long as the neckboard socket is the same type/# of pins (basically form factor) as the tube, the chassis determines the resolution of the tube. Someone with more experience in that can chime in. If the neck of the tube is the same diameter, you can do a yoke swap from the old tube, too. But I think you know that if you've done a swap before. But, that potentially leads to a lot of time later to get the convergence/purity/geometry perfect.

Looks like you're going all out on the restoration of this. Hope it works out for you. And that link of the fellow doing a restoration of a set of those cabinets (EDIT!: He's doing San Francisco Rush! Sorry! But cabs look identical.) seems to have done a lot of these same repairs.