Guitars of Love ...
musical electronic projects, repairs and service tips (scroll down)

** 'guitars-of-love' is based in Melbourne Australia, which has 240VAC mains supply **


  • - Originally written by my electronics teacher James Wemm at Box Hill Institute, lessons on all the basics of electricity and basic electronics in pdf format. I took over the gig of teaching electronics to audio production students at BHINST from Jim in 2008, and made some changes and added to the series as well. It's all here from the very start including the all important Ohms Law (the basis of all analogue electronics), through to how capacitors and inductors work, the function and purpose of resistors, and how semiconductors work too. The modules contain simple circuits explaining the principals of power supplies and amplifiers and speaker crossovers

I also have a license for 'In-service Safety Inspection and Testing of Electrical Equipment' (AS/NZS 3760:2010) which means I can test guitar amps, mixing desks, PAs, electric tools etc for electrical safety and tag them. Licence No. 046880

Apart from playing guitar I am an electronics technician with many years experience in the servicing of electronics ranging from valve amplifiers to digital cameras. I have been doing my own guitar repairs for a couple of decades now. Based in Melbourne, I specialise in music related gear such as guitar amps, keyboards, P.A. gear etc. I also maintain a keen interest in retro Hi Fi which is becoming very popular on eBay and the like.

 

                   

 

I enjoy working on vintage equipment as much as anything - it's part of the love.

Custom gadgets & projects

Note that I include as larger images as possible on these pages for clarity so they won't always fit into the screen.

 

My latest FET preamp for guitar or bass, with great tone function and a moderate FET overdrive / compression function. It makes a great bass DI and is a definite winner! It uses a FET input which works like a 12AX7 valve, and another FET after the tone controls to add valve like OD. The bass knob also doubles up as an extra OD for a warm and punchy retro sound by switching out the -ve feedback in the bass tone circuit. There is also a treble boost switch to give that Fender amp like twang.


 





 


 

Custom optically coupled GOL tremelo pedal - it's a ripper!



 

...build up your own vintage OD pedal - one of the best OD pedals ever made!

Sick of dozens of crappy 'wall warts'?
Build your own regulated 9V DC unit.

My original, full control GuitFET I designed and built around 1994 - 1996, and put through many changes. The original one features adjustments for input level / bass / treble / treble boost switch / bass cut switch and OD level with two OD stages, one using one FET, and the other using two FETs daisy chained, and volume out. I had no design planned for the vero board and just add libbed as I went. It's by far the most complex circuit but, the best one I have made. The sound is pure velvet.
I have built a new version which is more sophisticated in that it uses two separate OD stages which are switched electronically with a bistable switch. The new one has more tonal variation, but is more complex requiring two vero boards; one for the power supply and bistable cct, and one for the preamp itself. Click on the page for details

An all-discreet component, class 'A' unbalanced to balanced converter DI box. Either straight mono or stereo for Hi Fi apps. Mains powered only!


Tandy 'Realistic' PZM mic pre-amp ... get rid of those battery / transformer packs!

 

The 'Super DI box'. It runs on phantom power, 9V battery and mains! Converts from UB to Balanced and balanced to UB - very handy in an audio workshop.

The ultimate 9 volt power supply....

Toroidal powered with full 1 amp capability :

At the far right, pics of one knocked up by Eric Johnson in the USA using all the same components except for the mains toroidal transformer which is 120VAC instead of 240VAC. He's done an excellent job too!

At left, a 'Spyder' version built by Tristan, incorporating a power transformer with multiple isolated secondary windings. Apart from achieving regulated DC various voltages ranging from 9V to 24V, each supply is totally isolated from the other, and from earth.

Full marks for this effort too!


The Shin-ei Reslytone RT-18 circuits, repairs and useful mods

Update the indicator bulb circuit board to a brighter and more efficient LED one

True bypass mod where I use the Resly as an overall bypass for all other FX pedals as well as the Reslytone itself

kelvin@guitars-of-love.com