Flashlamp query

[paddythegreek]

Was checking out a Radical i 'd bought and 3 flashlamps (all connected) in the backbox and one on the playfield didn't flash. Turns out the 5w 3 ohms resistor had gone. Look in the manual and said resistor should be 5.6 ohms. I've installed a 5.6 but none of the flashlamps are very bright. As i dont know how bright they were with the 3 ohms one, would 2.6 ohms make that much difference?

 

[Jay Walker]

Hi, paddy,

Generally speaking, the more bulbs connected (in parallel)* the higher the value of the limiting resistor. 2.6 Ohms is probably a bit too low for 4 bulbs - I'd try something in between.

* Williams changed the flashbulb circuits from series to parallel with 'Fire!'. That game ate up #89 bulbs, since its little resistor boards under the playfield had limiting resistors suitable for the series connection (too low for the parallel circuit). After changing these to a higher value, the lamps would hardly light in test mode, but were okay during play.

 

[Moonraker]

It's the wattage that you need to keep an eye on. The 0.4 of an ohm will probably see them be a little brighter but if 5w wasn't man enough to take the load then find one that's 10w or more to do the job.

 

[paddythegreek]

2.6 ohms is the difference between what was installed and what is now installed. It was a 3 ohm not .3. Its now 5.6. Ken

 

[Moonraker]

2.6 ohms is the difference between what was installed and what is now installed. It was a 3 ohm not .3. Its now 5.6. Ken

D'oh...!

 

[paddythegreek]

Have installed a 5w 3ohm resistor. It actually reads 3.5 ohms but at the moment its working ok with bright flashlamps. A 10w one won't physically fit unless you can get 10w ones the same size as 5w ones. My 10w are twice the length.