[vcf-midatlantic] Received H11-a shipping mess!

Richard Cini rich.cini at verizon.net
Wed Feb 10 22:06:41 EST 2016

Jonathan —

	The M7270 LSI-11 is DEC-branded (forgot to write down the revision number). The SLU and RAM are Heathkit branded. I have the LSI-11 and SLU manuals but no manual for the RAM. That’s easy though — it has simple jumpers for the bank enable (0-3 on board #1 and 4-6 on board #2; bank #7 disabled).
	The third toggle switch is a 7/16” threaded toggle drilled into the front panel. It’s a simple SPST connected to the power supply board with a two conductor cable and nowhere else. Without a schematic I don’t know what it’s connecting to. There is no additional cable to the backplane or any other board.

	I’ll try to post a few pictures this weekend. I’m really disappointed at the poor packing job. There’s a lot of fixing to do. I might even consider making cherry or walnut side panels as a replacement for the plastic composite.


Rich Cini
Collector of Classic Computers
Build Master and lead engineer, Altair32 Emulator

On 2/10/16, 8:59 PM, "vcf-midatlantic on behalf of Systems Glitch via vcf-midatlantic" <vcf-midatlantic-bounces at lists.vintagecomputerfederation.org on behalf of vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:

>> It’s a two-switch front panel with a 3rd toggle switch connected to two posts on the power supply board 
>If it's like a LSI system, it's probably for the Line Time Clock (LTC).
>> The CPU has 5 40-pin chips (two purple ceramic and three PDIP). Supposedly the H11 has a monitor PROM or something like it, but I don’t see anything like a PROM on the board. Guess I have to wait until I get it running!
>Sounds like the LSI-11 chipset (based on the WD16 multi-package CPU). If so, it's got ODT microcoded right into the processor. You'll still need some working RAM and a SLU at the typical address for it, though. Do you know if it's just a rebranded DEC board?
>> Is there anything else I should know about the H11 while bringing it up?
>From what I know about the H11, I believe some of their cards are just DEC boards (CPU, possibly some of the RAM options). Can you post pictures of your boards for us to identify?

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