---
title: "E-Z Load Modification"
type: "article"
slug: "e-z-load-modification"
url: "http://localhost/article/e-z-load-modification/"
markdown_url: "http://localhost/article/e-z-load-modification.md"
published_at: "2026-01-15T12:53:48+00:00"
modified_at: "2026-06-21T23:37:31+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "Based on the information on the recorder to computer interface for the ZX81 which appeared in the Jan 8 3 issue of QZX, I have experimentally devised the following simple matching network for my machine. It consists of only two parts aside from the connectors and enclosure - a 0.1 or 0.2 uF capacitor and…"
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  - name: "TS 1000"
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model:
  - name: "Timex/Sinclair 1000"
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indiv:
  - name: "Edwin Solov (K2SE)"
    slug: "edwin-solov-k2se"
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publication_r:
  id: 21219
  title: "QZX"
  type: "periodical"
  url: "http://localhost/periodical/qzx/"
authors_r:
  - name: "Edwin Solov (K2SE)"
    slug: "edwin-solov-k2se"
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volume: "1"
issue: "7"
issues_articles:
  - id: 62163
    title: "QZX v1 n7"
    type: "issue"
    url: "http://localhost/issue/qzx-v1-n7/"
pages: "5"
pubdate: "June 1983"
archive_link: false
---

# E-Z Load Modification

Based on the information on the recorder to computer interface for the ZX81 which appeared in the Jan 8 3 issue of QZX, I have experimentally devised the following simple matching network for my machine. It consists of only two parts aside from the connectors and enclosure – a 0.1 or 0.2 uF capacitor and an audio output transformer. The transformer is used in an attempt to match the low impedance audio output of the recorder to the higher input impedance of the ZX81’s ‘ear’ input port. The capacitor was added after observed on a scope that the signal input from the recorder was riding on a substantial 6Ø Hz noise base. The capacitor removed that source of irritation very well. Since using this circuit, I have experienced substantial improvement in the reliability of the ‘LOAD’ operation. I did find, however, that this modification required me to increase by about 10% the volume setting of the recorder to obtain dependable performance.