Motherboard revisions Apple II and II+

The motherboards of APPLE II and II PLUS are divided into two groups:

- NON RFI cards
- RFI cards

What is this RFI story?

RFI = Radio Frequency Interference. Clearly, a NON RFI machine disrupts radio broadcasts.

Determine if it is an APPLE II or APPLE II + by date?
Roughly, the dates on the market seem to have been as follows:

1977 to 1978 : APPLE II with maps REV.00 to REV.03
1979 to 1980 : APPLE II and APPLE II + with REV cards. 04 to REV.07
1981 to end : APPLE II + RFI cards exclusively

NON RFI cards are:

A single and very rare model.
There is NO NUMBER 820-0001-00 as we sometimes see on some sites or user group posts!

REVISION 1: P / N 820-0001-01. with Movable Jumpers Blocks
P / N 820-0001-02. with Movable Jumpers Blocks
P / N 820-0001-03. with Movable Jumpers Blocks
P / N 820-0001-04. Welded 16K Jumpers Blocks

Models 820-0001-05 and 820-0001-06 do not seem to be known.

REVISION 7: P / N 820-0001-07. Disappearance of Jumpers Blocks

Models 820-0001-08 and 820-0001-09 do not seem to be known.

If the revision 0, 1, 2 and 3 (models 820-0001-01 820-0001-02 and 820-0001-03) belong only to APPLE II, on the other hand the other types of NON RFI cards are either on APPLE II is on APPLE II Plus, the distinction being made (in addition to the type of ROM which is not sufficient) by the serial number which is of the form A2S1-NNNNN for APPLE II.
RFI cards are:

REVISION 1: P / N 820-0044-01.

REVISION 2: P / N 820-0044-C. P / N 820-0044-D.

Models 820-0044-A and 820-0044-B do not seem to be known.

It should be noted that RFI cards always belong to APPLE II Plus. The drawing below shows you the motherboards that make up the APPLE II and APPLE II PLUS. The overlap area of ​​820-0001-04 and 820-0001-07 is a delicious uncertainty ...

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