kr 9400 help needed

M

maclvrbr

AK Subscriber

Subscriber

• Dec 2, 2013

• #1

I recently recapped the power supply and right left channels. My problem is low volume with a buzz even when knob is turned to maximum. I have the +14 and -14 voltages from power supply. Thanks for the help

 

EchoWars

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• Dec 2, 2013

• #2

New issue, or old? IOW, was it f'd up before you recapped it?

 

M

maclvrbr

AK Subscriber

Subscriber

• Dec 2, 2013

• #3

kr 9400

Its a new issue. Thanks for responding

 

EchoWars

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• Dec 3, 2013

• #4

Speaker relay engaging?

 

M

maclvrbr

AK Subscriber

Subscriber

• Dec 3, 2013

• #5

kr 9400

yes. I am getting sound from speakers. The volume knob must be turned fully clockwise, but volume is low and has a slight hum. Ideas? thanks

 

EchoWars

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• Dec 3, 2013

• #6

All that comes to mind is the obvious...check your work, look carefully for broken wires (Kenwood used a lot of solid-core wires that are easy to break).

 

M

maclvrbr

AK Subscriber

Subscriber

• Dec 4, 2013

• #7

kr 9400

I have rechecked my work and would appreciate any other ideas. How can I diagnose the TA 7136p IC's if they were bad? I have replaced the 4558's as a friend gave them to me some time ago. Thanks in advance

 

EchoWars

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• Dec 4, 2013

• #8

Well, if you have a signal going in, but none coming out...

The 7136P is a single channel device, so I'd find it tough to believe that both devices are suffering from the same issue. Really need a scope here to follow the signal and see where it's being lost.

 

dnpainting

Super Member

• Dec 5, 2013

• #9

Low sound @ full volume From all sources including external? Phono, Aux, Tape etc.?

Tape monitor switch('s) came to mind.
Broken Wire like Echo said. Pinout Wrong/orientation On 4558's or no good. Put old back in, one at a time.

 

Last edited: Dec 5, 2013

M

maclvrbr

AK Subscriber

Subscriber

• Dec 5, 2013

• #10

kr 9400

Thanks for the replys as I am trying not to pull my hair out. I tested aux tape and phono and all inputs gave me low volume with knob turned fully clockwise. I would love to find a broken wire somewhere to fix and actually have repaired 2 red broken wires that attached to the power supply and a few others on the power supply board as well. I am sending a pic of the 4558 opamps I installed. From what I understand the orientation was that the small circle on top indicated pin 1 on the tone control board. Any other ideas appreciated.

 

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EchoWars

Hiding in Honduras

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• Dec 5, 2013

• #11

Yes, small circle is Pin 1. As shown, your orientation is:

8-7-6-5
1-2-3-4