Pole position ARii power low voltage

Gorf69

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I have a power supply that is only getting about 1 volt at the board and 3 volts at the 10.3 test site on the AR board.

I purchased a repair kit because the cr1 and r30 were burnt.

I am wondering if I purchased the wrong kit version. Are the resistors interchangeable between versions
IMG_3090.jpeg
 
Hey fellow Minnesotan!

If your 10.3V is low, check the bridge rectifier on the underside of the power brick as well as all the fuses and fuse connections. If that isn't solid the AR2 has no chance of working.
 
What beerNpretzels said.

The 10.3 is the input voltage to the AR. 5V is the output. If you have no 10.3, the problem isn't the AR (though the AR could have other issues on its own).

Burned resistors on the AR are due to dirty edge connector fingers on the game board(s). Clean the fingers with a fiberglass pen and then apply DeOxit. DO NOT go out and replace the entire harness edge connector, it is not necessary. The problem is oxide on the fingers of the game board, and a cleaning is all that is needed. Buy these now, and clean the fingers on every game you own. It will save you lots of headaches and future problems:

https://www.ebay.com/itm/195190435832
https://www.ebay.com/itm/401568675610

It normally isn't necessary to recap AR's. The original caps are fine. All you need to do on most of them is replace the 2N3055, as that's the part that does the heavy lifting, and they should all be replaced with a quality replacement part from a trusted source. If the R29 and/or R30 resistors are burned, just replace them. They are both 10 ohm, 1/4 watt. DO NOT use 1/2 watt. Shotgun kits for AR's are not necessary. People waste too time and money replacing parts that do not go bad, and are not the problem.

The most common cause of low 10.3 is an oxidized/burned tab on the fuse block (or dirty fuses). DO NOT go out and buy a new fuse block. Inspect and clean the one you have first, as that's usually all that's needed, and the original block is nicer than the cheap Chinese replacements.

See posts #17 and 18 in this thread for an example of the issue:



If the fuse block is clean, pull the brick and look for burned wires underneath the brick, especially around the rectifier. These sometimes oxidize as well, and cause bad connections.
 
Last edited:
Link to the fiberglass pen is broken. Just fyi

What beerNpretzels said.

The 10.3 is the input voltage to the AR. 5V is the output. If you have no 10.3, the problem isn't the AR (though the AR could have other issues on its own).

Burned resistors on the AR are due to dirty edge connector fingers on the game board(s). Clean the fingers with a fiberglass pen and then apply DeOxit. DO NOT go out and replace the entire harness edge connector, it is not necessary. The problem is oxide on the fingers of the game board, and a cleaning is all that is needed. Buy these now, and clean the fingers on every game you own. It will save you lots of headaches and future problems:

https://www.ebay.com/itm/401568675610

It normally isn't necessary to recap AR's. The original caps are fine. All you need to do on most of them is replace the 2N3055, as that's the part that does the heavy lifting, and they should all be replaced with a quality replacement part from a trusted source. If the R29 and/or R30 resistors are burned, just replace them. They are both 10 ohm, 1/4 watt. DO NOT use 1/2 watt. Shotgun kits for AR's are not necessary. People waste too time and money replacing parts that do not go bad, and are not the problem.

The most common cause of low 10.3 is an oxidized/burned tab on the fuse block (or dirty fuses). DO NOT go out and buy a new fuse block. Inspect and clean the one you have first, as that's usually all that's needed, and the original block is nicer than the cheap Chinese replacements.

See posts #17 and 18 in this thread for an example of the issue:



If the fuse block is clean, pull the brick and look for burned wires underneath the brick, especially around the rectifier. These sometimes oxidize as well, and cause bad connections.
 
What beerNpretzels said.

The 10.3 is the input voltage to the AR. 5V is the output. If you have no 10.3, the problem isn't the AR (though the AR could have other issues on its own).

Burned resistors on the AR are due to dirty edge connector fingers on the game board(s). Clean the fingers with a fiberglass pen and then apply DeOxit. DO NOT go out and replace the entire harness edge connector, it is not necessary. The problem is oxide on the fingers of the game board, and a cleaning is all that is needed. Buy these now, and clean the fingers on every game you own. It will save you lots of headaches and future problems:

https://www.ebay.com/itm/195190435832
https://www.ebay.com/itm/401568675610

It normally isn't necessary to recap AR's. The original caps are fine. All you need to do on most of them is replace the 2N3055, as that's the part that does the heavy lifting, and they should all be replaced with a quality replacement part from a trusted source. If the R29 and/or R30 resistors are burned, just replace them. They are both 10 ohm, 1/4 watt. DO NOT use 1/2 watt. Shotgun kits for AR's are not necessary. People waste too time and money replacing parts that do not go bad, and are not the problem.

The most common cause of low 10.3 is an oxidized/burned tab on the fuse block (or dirty fuses). DO NOT go out and buy a new fuse block. Inspect and clean the one you have first, as that's usually all that's needed, and the original block is nicer than the cheap Chinese replacements.

See posts #17 and 18 in this thread for an example of the issue:



If the fuse block is clean, pull the brick and look for burned wires underneath the brick, especially around the rectifier. These sometimes oxidize as well, and cause bad connections.
Can you explain why a 10 ohm 1/2 watt resistor CAN NOT
be used in place of a 10 ohm 1/4 watt resistor.
 
Can you explain why a 10 ohm 1/2 watt resistor CAN NOT
be used in place of a 10 ohm 1/4 watt resistor.

The short answer is fire.

Electrically, a larger power-rated resistor will make a circuit work, if that circuit works properly. The problem arises when it doesn't.

In the case of these AR's, when the main 5V or ground path between the AR and game board becomes oxidized/dirty, or just broken (e.g., from someone only putting the edge connector on partway), several amps of 5V gets shoved through the 10-ohm sense resistors. Way more than they are rated for.

When this happens, they normally glow red and burn. Resistors tend to be pretty tough things, and will hang on for a long time before they burn up. But eventually they go open, and kill the circuit.

Several amps through a 1/4 watt resistor will smoke, glow red, and burn open. Several amps through a 1/2 watt resistor will make a much larger fireball before it goes open. And if it's in a cab with a wood bottom, which also might have a layer of dust, or a mouse nest below the AR, if burning bits of resistor fall off the AR, you're looking at a fire hazard. And it's stuff like this that causes house fires. (Ask me how I know.)

So that's why you don't want the larger resistor, and stick to the 1/4 watt one. If there's a chance something is going to burn up in your cab, you don't want to change things to make even bigger fireballs, increasing fire risk in 40-year-old dried out wooden cabinets full of dust.
 
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