---
title: "Direct Video Mod"
type: "article"
slug: "direct-video-mod"
url: "http://localhost/article/direct-video-mod/"
markdown_url: "http://localhost/article/direct-video-mod.md"
published_at: "2026-01-14T23:57:05+00:00"
modified_at: "2026-01-15T00:12:42+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "Here's a video reverse/clean-up mod that started as W4MHQ's \"Direct Video Output\" in QZX VOL.1 NO. 2. Like W4MHQ's, this circuit uses a 75451 to do the output switching. The values of the resistors that define the pedestal and P-P video levels of the output were changed to very nearly duplicate the video signal at…"
category:
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  - name: "TS 1000"
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model:
  - name: "Timex/Sinclair 1000"
    slug: "ts-1000"
    taxonomy: "model"
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indiv:
  - name: "Fred Nachbaur"
    slug: "fred-nachbaur"
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publication_r:
  id: 21219
  title: "QZX"
  type: "periodical"
  url: "http://localhost/periodical/qzx/"
authors_r:
  - name: "Fred Nachbaur"
    slug: "fred-nachbaur"
    taxonomy: "indiv"
    url: "http://localhost/indiv/fred-nachbaur/"
volume: "1"
issue: "7"
issues_articles:
  - id: 62163
    title: "QZX v1 n7"
    type: "issue"
    url: "http://localhost/issue/qzx-v1-n7/"
pages: "4-6"
pubdate: "June 1983"
archive_link: false
---

# Direct Video Mod

Here’s a video reverse/clean-up mod that started as W4MHQ’s “Direct Video Output” in QZX VOL.1 NO. 2. Like W4MHQ’s, this circuit uses a 75451 to do the output switching. The values of the resistors that define the pedestal and P-P video levels of the output were changed to very nearly duplicate the video signal at pin 16 of the ULA, and provides a higher (lv) P-P video level as preferred by most commercial monitors.