Atari A/R II: Too high +5v

[Dave in Pa]

I've got a few different A/R II boards I'm trying to get working.

I've tested them on a couple of different power blocks (voltages check ok on
the power blocks).

I've got 3 of them that are giving around +12v to +13v on the +5v line. The
adjustment pot doesn't make any change. I put Bob Roberts repair kit on one
of them, no change.

All the other voltages check okay, only the +5v line is off. Any
suggestions on what would cause this?

Thanks,
Dave in Pa

[Chuk]

I have had a couple of AR boards that read +12 on the +5 without a load. As
soon as I hooked up a board, they dropped to +5. Not saying this is your
case, but it's happened to me more than once.

"Dave in Pa" <q_b...@adelphia.net> wrote in message
news:r-Odnc9GecPwVK3b...@comcast.com...

[Jeff]

Hi;
Have you checked the LM305?
Jeff

[Dave in Pa]

Jeff <jetu...@earthlink.net> wrote in message
news:1177642545.7...@t38g2000prd.googlegroups.com...

I was wondering if it was the LM305. Is it a common failure? I'm curious
why Bob Roberts doesn't include it in his kit.

Is there a way to test the LM305 or just replace it?

I've heard others say that the voltage will drop with a load on it, but I
have a working one that meters correctly without a load. I don't really
want to send +12v into my Food Fight PCB.

[Jeff]

On Apr 27, 9:14 am, "Dave in Pa" <q_b...@adelphia.net> wrote:
> Jeff <jetuse...@earthlink.net> wrote in message

Don't do it
I've been told in the past that the voltage will drop when loaded but
every time I investigate the situation further, I discover the failed
component.
I think the LM305 goes for about $3- alot cheaper than a PCB!!
Jeff

[goo...@brentradio.com]

Don't forget to do the sense mod as well.

http://www.stickycarpet.com/pinx/pp2page2.html

http://www.ggdb.com/KB.aspx?c=Coin-Op&s=Arcade&vid=1775&kb=2

Brent

[Dave in Pa]

I've orderes a few LM305's and I'll see it that fixes them up.

Jeff <jetu...@earthlink.net> wrote in message

news:1177729858.6...@n76g2000hsh.googlegroups.com...