Heathkit H88 and H89 Information

This document was updated on Monday, 28 March 2005.
Internal changes only; no changes to content.


There are dangerous voltages inside this unit (up to 15,000 volts). Be very careful when performing the following adjustments. If in doubt, have a qualified professional adjust the unit for you.

CPU Board Switch Settings

Switch S501
Switch Section Default Setting Description
0 0 Not used; leave at 0
1 0 Not used; leave at 0
2 0 Not used; leave at 0
3 0 Not used; leave at 0
4 0 Not used; leave at 0
5 0 Performs RAM memory test at reset. Must be set to 1 to stop.
1 Normal
6 0 Sets the baud rate to 9600 when both switches are at 0. Other positions are undefined.

For adjustments on the Terminal Logic Board and the Video Board, refer to the H19 Web page.

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