Harry's Homebrew Homepages
Harry Lythall

Updated 03th June 2024

Welcome to Harry's Homebrew Homepages; a resource for radio, hamradio and electronics in general.

If you have any technical questions, then please visit my
messageboard at http://sm0vpo.forumotion.com
(Opens in a new window)

HHH is still hosted on a Raspberry Pi, beside my bed. I also have a mirror at sm0vpo.altervista.org. (decided not to have a mirror beside the bed ;-)

A "must view" M0DAD pedestrian mobile. When I spoke to him he was walking, and I only had an 80cm loop out of the window in Sweden!!

Most recent projects are:
Arduino RC Encoder 6-CH (8-CH)
Arduino RC Servo Tester/1CH Encoder
RC Servo Tester / 1.CH Encoder
3D Printed Portable HF Antenna
AF source using your RF generator
Retro audio amplifier - for the bench and fun
Custom value (bespoke) capacitors
Ferrites for RF
Window Cable Transition
200mW FM TX (good filter design)
Pathlosses explained
Basic TX filters for HF/VHF
HF antennas in small spaces
Designing Transformers
Voltage Regulators
Mic Audio Compressor
AF Generator 01 (retro design)
CMOS Scope Timebase
160mW FM TX by Joy Mukherji
3D printed 10KV tunng cap for 20m antenna
3D printed 6P Jones plug for FT-101ZD
PIC based Frequency Counter
3D printed Denco coil substitute
20 metre frame antenna (small :-)
GDO revisited (GDO-2)

Searching for schematics? Circuit Diagram - Schematics is the language of electronics. It provides a concise and comprehensive diagrammatic description of a circuit. www.schematics.com allows users to connect and share designs and ideas in a like-minded community.

Did you know that I have written a book? "How to please a woman in bed". Nothing to do with sex - I suggest a man should get up early on Sunday morning, make breakfast and serve it in bed. Believe me, it is a lovely romantic start to any Sunday, and can give a massive kick to any relationship.

There are several links:
My book on Amazon
My book on Adlibris (SWE) (right-click and select "open in new tab")

Paperback: ISBN 9781910394717
Hardback: ISBN 9781910394724

Anyway, I hope you have fun with my homepages. Very best regards from Harry Lythall - SM0VPO, (M rsta), Sweden.

Site Summary

Homebrew Projects are located at:

If my server crashes then there is an alternative at:

Download files are located at:

Visitors Circuits are located at:

About 16,000 PDF datasheets are located at:

= Photograph illustrations included with the project.
= I have recently updated this project (Obvious, really!!!)
= Recently added (no timeframe - I'm quite informal)
= Not new (but I want it to be noticed by someone)
= The picture file is missing - please let me know.

Here you can e-mail Harry, but if it is a technical question then please be so kind and use the MessageBoard. Thank you.


During 2005 I had 202,000 visitors
During 2006 I had 182,000 visitors
During 2007 I had 166,500 visitors
During 2008 I had 279,000 visitors
During 2009 I had 210,000 visitors
During 2010 I had 641,193 visitors
During 2011 I had 959,762 visitors
During 2012 I had 2,800,000 visitors*
During 2013 I had 1,671,882 visitors*
During 2014 I had 2,140,969 visitors
During 2015 I had 2,054,169 visitors
During 2016 I had 2,313,061 visitors
During 2016 I had 2,433,120 visitors

(* = estimated from fragmented LOG files)

2015, 2016 and 2017 is the total of the two sites www.sm0vpo.com and sm0vpo.altervista.com.