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Mpodgor
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Username: Mpodgor

Post Number: 1
Registered: 7-2012
Posted on Thursday, August 23, 2012 - 6:43 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have this kl-503 that has a resistor that is fried. It is R8. I need the value to replace it. Any help would be appreciated! The board is rel 1.2
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Mpodgor
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Username: Mpodgor

Post Number: 2
Registered: 7-2012
Posted on Thursday, August 30, 2012 - 2:53 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Here is a reply that I got from RM Italy:

R8 is a 100 Ohm carbon film resistor. If you replace it, it must be a non
inductive resistor type. R8 is a balancing resistor across the output
combiner. If its getting too hot then usually it is a sign one or more
transistors are damaged and are not giving full power. This causes an
imbalance in the combiner and current flows across R8. The amount of current
depends on how much the imbalance is.

The amp when driven with 4W or 5W (max) should output about 250W if you are
getting much less than this then this too is a sign that there could be a
problem.

Best regards,

Andrew
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Mpodgor
New member
Username: Mpodgor

Post Number: 4
Registered: 7-2012
Posted on Tuesday, September 18, 2012 - 5:54 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Now the damn resistor burns up. Maybe bad mosfets? Anyone know what P/N for the 9 mosfets? RM Italy seems to keep it a secret. The face of all the mosfets are sanded so there is no printing on the face. What's that all about????
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Wheelco505
Member
Username: Wheelco505

Post Number: 90
Registered: 12-2004


Posted on Saturday, October 06, 2012 - 7:09 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

are 4 1446's in the new ones?
james wheeler

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