WG U5000 tube compatibility...

[MKFan4Life]

I am doing a cap kit and flyback replacement for a friend on his WG U5000 chassis.  It does both 25K and 15K by changing a jumper on the chassis.

I really want to do some testing after I finish the work, but I don't have the tube that was mated to this chassis.  (He shipped the chassis to me, because I have a bit more experience with soldering.)

I have always heard you need a compatible yoke to work with your chassis, and that damage might occur if you try, for example, a tube that was mated with a standard-res chassis and a chassis that is medium-res.  Since this has the standard-res jumper, would it hurt to try the chassis on one of my tubes with standard-res WG K7000's or Hantarex Polo currently installed if the U5000 jumper is set to 15K?  (They are 25" tubes and the U5000 chassis came from a 25" medium-res monitor.)

If this wouldn't work, I do have a medium-res monitor in my Gauntlet Legends cab, but it has a 27" tube.  (Neotec NT-2701, medium-res only chassis.)  Would that work if the jumper stays on 25K, although I'd assume it wouldn't fill the entire screen?

Thanks for any help guys!

[MKFan4Life]

Anybody have any help on this?  Thanks in advance... 

[grantspain]

vertical 5 ohms
horizontal 2 ohms

will run on a hantarex polo yoke

[MKFan4Life]

vertical 5 ohms
horizontal 2 ohms

will run on a hantarex polo yoke

Thanks.  Will the tube be able to be used in the medium-res mode for testing?  Just wondering.  This chassis appears to have had a partial upgrade kit for the "Vertical Sweep" performed, and apparently you must complete a connection from a terminal strip with a large resistor on it to enable 15K operation.  It is currently installed in such a way as to enable 25K mode.  Someone did not complete the entire upgrade to the vertical sweep, nor did they install the other 2 kits I have read about which upgrade the power supply and horizontal output for the chassis. 

[grantspain]

yes you can run in both 15k and 24k using similar yokes

the wire link should be a white wire on right of chassis,should be a 2 pin connector that goes to a single pin header
with it disconnected i think the picture is 15k,it makes only some difference to vertical position if i remember

[MKFan4Life]

yes you can run in both 15k and 24k using similar yokes

the wire link should be a white wire on right of chassis,should be a 2 pin connector that goes to a single pin header
with it disconnected i think the picture is 15k,it makes only some difference to vertical position if i remember

Thanks for the reply man!

[MKFan4Life]

vertical 5 ohms
horizontal 2 ohms

will run on a hantarex polo yoke

I have one tube that was mated with a WG K7000 series chassis, and the yoke measures 11.5 ohms vertical & 3.2 ohms horizontal.  Too far off huh?   

[grantspain]

those measurements sound like a 19" tube

[MKFan4Life]

those measurements sound like a 19" tube

Had my meter on the wrong setting.  It's a 25" tube.  It is 1.4 Ohms and 9.8 Ohms.  (Hor & Vert respectively)  Sorry.  Still not close enough though I wouldn't think.

Might have to pull the Hantarex Polo yoke wires loose on the MK2 and check to see what I get from that one.  The other tube those readings are for is just conveniently out of a cab at the moment and easily accessible. 

The vertical sweep update kit instructions says this about the connection of the large resistor terminal strip:

Wells-Gardner U-5000/U-2000 Vertical Sweep Upgrade Kit

TP205 located directly in front of vertical deflection IC U601. Connect it such that TP205 mates with the proper connector position for the respective horizontal frequency operation:
WITH TP205 CONNECTED to the white wire for 15 Khz (CGA or standard) operation.
WITHOUT TP205 CONNECTED to the white wire for 25 Khz (EGA or medium) operation.
13. Affix the resolution/frequency select label to the side of the bottom pan directly in front of TP205.

It is currently connected to the position on the plug WITHOUT the white wire.  (And the monitor came to me with the jumper set to medium-res mode and was on a medium-res monitor.)  There is hot glue on the connection so it has been that way a good while.

Guess I need to remove the glue and switch to the position WITH the white wire connected to TP205 to set this to standard-res then, as well as switch the jumper to the 15K setting.  (He wishes to connect this back up as a standard-res when I return it to him to run an MK3 board and War Gods board (set to 15K output) on a JAMMA switcher.

[MKFan4Life]

I had the owner test his tube at home and he said he was getting 1.9-2.0 Ohms Horizontal and 7.5-8.0 Ohms Vertical.  What range of readings could I safely stay within for testing if I can't get an exact match?  Thanks in advance.

[MKFan4Life]

Just checked my monitor in the MK1 (K7400) and the tube measures 1.2 Ohms Horizontal and 7 Ohms Vertical.  Wonder if this is close enough to 1.9-2 Ohms Hor. and 7.5-8 Ohms Vert. the owner measured from the original tube from the U5000?

[grantspain]

yep

[MKFan4Life]

yep

Got the U5000 going great on the tube that was in my MK1 (had a WG K7400 in it).  So the small difference in resistance between it and the original U5000's tube doesn't seem to have been a problem.  Cheers.