Nad C-420 Service Information

NAD C420

MODIFICATION

PROBLEM:

When a frequency of 10.25 MHz or higher is stored into preset 3 the unit may change this frequency to

12.8 MHz less after receiving any remote command (102MHz becomes 89.2MHz).
This occurs even with other brand’s remote commands.

CAUSE:

This is a software bug.

SOLUTION:

There are two possible solutions for this fault:

• The best solution is to replace the CPU, this will keep the partnumber mentioned in the service

manual: LC866448B (U201)

• The fast solution is to disable the IR receiver, this is only possible if you are 100% certain the

customer will not use this function.

It is advisable to perform this modification whenever a unit comes in for service.

PRODUCTION:

The new CPU will be installed from serial: G0XC42003201

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Service Tip C420

Preset memory circuit change

PROBLEM: When a frequency of 102.5MHz or higher is stored into preset 3
the unit may change this frequency to 12.8MHz less after receiving any
remote command (102.5MHz becomes 89.2MHz). This occurs even with other
brand’s remote commands.

CAUSE: This is a software bug.

SOLUTION: The solution is to replace the CPU, this will keep the part
number mentioned in the service manual: LC866448B (201).

PRODUCTION:

This modification has been implemented in production from serial number: G0XC42003201

Contact:

NAD Electronics International
633 Granite Court
Pickering, ON Canada L1K 3K1
Voice: 905-831-0799 FAX [phone]
[e-mail]

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