# An Interview with Ken Shirriff

- Show: [The Amp Hour](https://hardwarepodcasts.com/podcast/the-amp-hour)
- Published: 2017-09-25
- Length: 1h 14m
- Episode: 361
- Page: https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff
- Listen: https://theamphour.com/361-an-interview-with-ken-shirriff/

## Summary

Ken Shirriff, who runs the blog Righto.com and formerly worked at Google, discusses his reverse engineering of vintage silicon and restoration of historical computing hardware. He details his process for creating die shots of 1970s chips using metallurgical microscopes and chemical etching, and explains the technical challenges of restoring a Xerox Alto computer, including replacing decaying foam and fixing incompatible TTL logic boards. Shirriff also analyzes the internal architecture of Apple power supplies, noting the presence of microcontrollers for safety handshakes, and compares the varied internal designs of standard components like the 555 timer and 741 op-amp across different manufacturers.

## Chapters

- [0:00](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=0) Introduction: Ken Shirriff and Righto.com
- [2:53](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=173) Die Shot Photography: Microscopes and Stitching
- [7:13](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=433) Etching Vintage Chips: Armor Etch and Acid
- [10:27](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=627) Counterfeit RAM and Touchtone Dialing Chips
- [13:04](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=784) Bitcoin Mining on Vintage Hardware
- [16:05](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=965) Restoring the Xerox Alto Computer
- [27:08](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=1628) Reverse Engineering the 76477 Sound Chip
- [48:25](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=2905) Sinclair Calculator and TI Patent Analysis
- [57:53](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=3473) Apple Power Supply Microcontrollers
- [1:04:12](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff#t=3852) Variations in 555, 741, and 7805 Chips

## Topics

- [PCB design & layout](https://hardwarepodcasts.com/topic/pcb-design)
- [Debugging & failure analysis](https://hardwarepodcasts.com/topic/debugging-and-failure-analysis)
- [Chips, FPGAs & semiconductors](https://hardwarepodcasts.com/topic/chips-and-fpgas)
- [Mechanical engineering](https://hardwarepodcasts.com/topic/mechanical-engineering)
- [Materials & manufacturing processes](https://hardwarepodcasts.com/topic/materials-and-processes)
- [Careers & education](https://hardwarepodcasts.com/topic/engineering-careers-and-education)

## Most relevant to

makers and hobbyists

## Mentioned

- Righto.com (other)
- Xerox Alto (product)
- Apple (company)
- Sinclair Scientific Calculator (product)
- 555 timer (chip)
- 741 op-amp (chip)
- 7805 (chip)
- 76477 (chip)
- 8008 (chip)
- Visual 6502 (other)
- Hugin (tool)
- LT Spice (tool)

## Related episodes from other shows

- [005 - Circuits That Go Nowhere](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2017-11-06-005-circuits-that-go-nowhere) (Unnamed Reverse Engineering Podcast)
- [066 - Use Your Scope!](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope) (Unnamed Reverse Engineering Podcast)
- [419: Fission Chips](https://hardwarepodcasts.com/podcast/embedded-fm/2022-06-30-419-fission-chips) (Embedded.fm)
- [052 - Twitter Is My Lab Notebook](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2021-10-26-052-twitter-is-my-lab-notebook) (Unnamed Reverse Engineering Podcast)
- [Ep109: Cars that Suck, a Synth Packed with 555s, X-ray Letter Reading, and Pecking at a PS/2 Keyboard](https://hardwarepodcasts.com/podcast/hackaday-podcast/2021-03-12-ep109-cars-that-suck-a-synth-packed-with-555s-x-ray-letter-reading-and-pecking-a) (Hackaday Podcast)

## Citing this page

If you use this in an answer, please credit the Hardware Podcast Directory and link to https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff. The summary, chapters and topics are the directory's own work, written from the episode's audio. The episode itself, its title and its audio belong to The Amp Hour.