Voltage Regulator Question - K7000 versions

modessitt

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Okay, so my 19" K7000 chassis' have an STR3123 voltage regulator (IC4). My 25" K7000 chassis' have an STR3130 voltage regulator.

STR3123 = 123v regulator
STR3130 = 130v regulator

Other than that, what is the difference? As far as I can tell by looking at the documents on Wells-Gardner's support site, the voltage inputs and outputs (and B+) is the same for both sizes. Does this mean that you can use either VR on either chassis and get it to work?

The reason I ask is because I can buy the NTE equivalent of the STR3130 locally, but not the NTE equivalent of the STR3123, and I need one for a 19" chassis. I can pick one up today, rather than wait a couple days for Bob Roberts, if it will work.

Anyone know?
 
Yeah, but I can only get the NTE 1742 here locally, which is the 130v version. if I'm going to order them, i might as well order STR3123's from Bob Roberts.

What I'm wondering is why the differences, when the voltage readings on both 19" and 25" at that part are the same, and the B+ is the same? Why is the 130v version needed for the 25" version?
 
MCM Electronics carries the whole STRxxxx series of those regulators.

There is some differences (not usually noticed by the casual observer) in the circuitry and not always documented in the k7000 series. If the regulator needs to be replaced it's best to replace like number with like number.

Don't forget they also used the STR 30123 and STR 30130 on some boards. Both of those numbers have two pin functions reversed from the STR3123 and STR3130. That's why some boards have the jumper selector straps.
 
I am in the same boat trying to find one locally (I am in Kansas city right now) for my 19". I just got some stuff from Bob Roberts and I would hate to have to order just this one part. Would nte 1776 work, the power dissapation is lower at 27w instead of 40w and I would have to switch pins 1 and 3? that was the only 125v one I could fine so far. any other suitable replacements I might try to look for or anyone local that might have one for me?
 
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I've never understood all those different STR voltage regulators Wells used in the K7000 series. I do remember one time, I had a 7000 chassis giving me fits. I had it working great with one exception....minor (but obvious) hula. I probed all over that thing....swapping parts...nothing...B+ was good....everything looked good. I had noticed the regulator had been replaced. I knew it was a different STR chip from the original because the legs didn't line up....there was jumper wire getting them to thheir correct position. It was done neatly...and I figured...all the K7000 STR chips do the same thing....right? Out of desperation, I swapped the STR chip with the correct one.....Problem fixed. I now try to keep a few of all 4 (or is it 5) varities (that Wells used through out the K7000 series) in stock.

Edward
 
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