Difference between revisions of "H765 Power System"

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The '''H765 Power System''' is a modular [[power supply]] system from [[Digital Equipment Corporation|DEC]], used in the [[BA11-K mounting box]]. In addition to [[main memory]] and [[device controller]]s on other [[PDP-11]]'s, the BA11-K was used to hold [[PDP-11/04]] and [[PDP-11/34]] [[Central Processing Unit|CPU]]'s.
 
The '''H765 Power System''' is a modular [[power supply]] system from [[Digital Equipment Corporation|DEC]], used in the [[BA11-K mounting box]]. In addition to [[main memory]] and [[device controller]]s on other [[PDP-11]]'s, the BA11-K was used to hold [[PDP-11/04]] and [[PDP-11/34]] [[Central Processing Unit|CPU]]'s.
  
A 5411086 board in the H765 supplies a modest amount of +15V [[Direct current|DC]] power to various [[backplane]]s mounted in the BA11-K, along with a [[line time clock]] signal, and [[Alternating current|AC]] and DC 'power OK' signals.
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The main [[transformer]] in the H765 supplies 20-30V [[Alternating current|AC]] to several [[DEC standard modular regulators]] (up to four, in spaces numbered '1' through '4') mounted in the H765, which provide other voltages such as +5V [[Direct current|DC]] to the [[backplane]]s in the mounting box.
 
 
It also supplies 20-30V AC to several [[DEC standard modular regulators]] (up to four, in spaces numbered '1' through '4') mounted in the H765, which provide other voltages such as +5V to the backplanes in the mounting box.
 
  
 
Generally the [[power harness]] supports only a fixed arrangement as to which regulator can be in which spaces; e.g. the BA11-K harness mandates that #2 and #3 hold [[H744 +5V Regulator]]s, #1 holds an [[H745 -15V Regulator]], and #4 may hold an [[H754 +20V, -5V Regulator]].
 
Generally the [[power harness]] supports only a fixed arrangement as to which regulator can be in which spaces; e.g. the BA11-K harness mandates that #2 and #3 hold [[H744 +5V Regulator]]s, #1 holds an [[H745 -15V Regulator]], and #4 may hold an [[H754 +20V, -5V Regulator]].
  
When the BA11-K is used in custom configurations to hold systems (such as the [[MJ11 memory system]] and [[MK11 memory system]]), other regulator configurations may be used, along with a custom harness; e.g. the MJ11 calls for two H744's and two H754's.
+
A 5411086 board in the H765 supplies a modest amount of +15V DC power to various backplanes mounted in the BA11-K, along with a [[line time clock]] signal, and AC and DC 'power OK' signals.
  
 
The harness used [[DEC power distribution connectors]] to provide power to standard backplanes; it normally used the [[DEC standard power wire colour coding]].
 
The harness used [[DEC power distribution connectors]] to provide power to standard backplanes; it normally used the [[DEC standard power wire colour coding]].
 +
 +
When the BA11-K is used in custom configurations to hold systems (such as the [[MJ11 memory system]] and [[MK11 memory system]]), other regulator configurations may be used, along with a custom harness; e.g. the MJ11 calls for two H744's and two H754's.
  
 
The H765 supported the standard DEC [[Remote Switching Control Bus]], so it could be turned off and on from a power switch elsewhere.
 
The H765 supported the standard DEC [[Remote Switching Control Bus]], so it could be turned off and on from a power switch elsewhere.
 +
 +
==Issues==
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 +
Some components on the 5411086 board are not protected by a [[fuse]]; if they fail 'closed', since AC to that board enters through contacts on the edge connector, those contacts may be damaged.
  
 
==See also==
 
==See also==
  
 
* [[H742 Power Supply]]
 
* [[H742 Power Supply]]
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==External links==
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* [http://www.glitchwrks.com/2019/06/05/pdp1110-psu-repair Repairing the PDP-11/10 Power Supply]
  
 
[[Category: DEC Hardware]]
 
[[Category: DEC Hardware]]

Revision as of 18:05, 6 June 2019

The H765 Power System is a modular power supply system from DEC, used in the BA11-K mounting box. In addition to main memory and device controllers on other PDP-11's, the BA11-K was used to hold PDP-11/04 and PDP-11/34 CPU's.

The main transformer in the H765 supplies 20-30V AC to several DEC standard modular regulators (up to four, in spaces numbered '1' through '4') mounted in the H765, which provide other voltages such as +5V DC to the backplanes in the mounting box.

Generally the power harness supports only a fixed arrangement as to which regulator can be in which spaces; e.g. the BA11-K harness mandates that #2 and #3 hold H744 +5V Regulators, #1 holds an H745 -15V Regulator, and #4 may hold an H754 +20V, -5V Regulator.

A 5411086 board in the H765 supplies a modest amount of +15V DC power to various backplanes mounted in the BA11-K, along with a line time clock signal, and AC and DC 'power OK' signals.

The harness used DEC power distribution connectors to provide power to standard backplanes; it normally used the DEC standard power wire colour coding.

When the BA11-K is used in custom configurations to hold systems (such as the MJ11 memory system and MK11 memory system), other regulator configurations may be used, along with a custom harness; e.g. the MJ11 calls for two H744's and two H754's.

The H765 supported the standard DEC Remote Switching Control Bus, so it could be turned off and on from a power switch elsewhere.

Issues

Some components on the 5411086 board are not protected by a fuse; if they fail 'closed', since AC to that board enters through contacts on the edge connector, those contacts may be damaged.

See also

External links