I'm not a web authour so apologies for the 'basic' look of this site.

However I'm sure that the practical Radio Amateur will find this to be a practical site.

In amateur radio my particuar interest is the Microwave bands. I'm currently active on all the bands 50Mhz to 2320Mhz + 10368Mhz. I have equipment under construction for 3400 and 5760Mhz too. I don't do too much design/development on these bands however so I'm afraid I'm a net 'consumer' of information in that area.

As a proffesional I work in PMR, which means I get access to some nice test gear (sadly nearly all of it stops at 1000Mhz!) , some useful software and servicing information. My company specialises in Kenwood stuff, so you will find a definate specialisation in that area. So for programming software for most of Kenwoods PMR range please visit :-

Zycomm Engineers Website

Most of the software available there is 'freeware' however recently Kenwood have been forced by commercial pressures to begin charging for programming software. So I'm afraid that if the software you downloaded demands a licence number it's chargable.

One of the things that PMR engineers seem to get 'put up for' is maintainance of Amateur repeaters. Several years ago I was asked to 'have a look at' GB3EE the Chesterfield 70cm box. As a result of several hours struggling to make the GB3US controller fitted to EE work properly I finally gave up and designed a new controller. The design is a simple one based around the 8051 microcontroller. Details are available on the following links.

Repeater controller features.

Repeater controller schematic.

Repeater controller builders FAQ

Repeater controller parts info.

Almost as soon as I had fitted my controller to GB3EE my boss (G3ZYC) was asking for one for GB3DY. Since he had supported the development work on the EE unit I quickly made a second one for DY. Word gets around and I have now supplied over 30 units. If you require any more info on this controler please email me

Email me.

Recently I was asked to 'make EE work with IRLP'. After some minor problems I managed to find a solution that suits all. I made a change in my software that causes CTCSS encode on the repeater output to go off immediately carrier is dropped on the input. The IRLP node is connected to a radio fitted with CTCSS decode and its 'busy' input is driven from an open collector output derived from carrier & CTCSS. This output is available on many PMR sets. This has the effect that only speech is passed to IRLP. None of EE's signal reporting or courtesy pips are ever heard on IRLP, this meets IRLPs requirements whilst still allowing users who wish to hear all the 'extras' given by EE to do so simply by switching off their CTCSS encoders.

Current users of SLE logic may upgrade for £5 on an 'exchange of 8751 basis'. However if you had 'special' software you will get back the 'standard' software as I'm afraid I just don't have time to maintain lots of specials. If you wish to upgrade please email me for details.





As a further enhancement I used the FSK beacon key output as a second 'CTCSS' input, the IRLP radio drives the CTCSS decoder fitted here which causes the S, I or W signal report to be replaced by a N signifying 'Networking' These modifications also open up the possibility of relatively easy networking of multiple repeaters using the EE controller, I have some thoughts on the relatively complex subject of repeater networking, if you are interested please look at

Repeater Networking Project

For a long while users of the EE controller have had to 'make their own arrangements' for remote switching of the switchable functions (HI/LO power, Talkthrough on/off and remote reset). I have now developed a small (45x60mm) PCB which will allow DTMF switching of up to 8 devices. The board has been designed to complement the EE contoller, but you could of course do all sorts of other things with it. The board accepts audio at a few 100 mV and provides 8 open collector outputs each able to sink 200mA from up to a 30V source. Built and tested boards will be available at £27.00 inc P+P.

Current things I'm working on are:-

Refitting my new shack

Ongoing development of my 'Amateur Voice Switch'



Anyhow hope you found the site useful, keep calling as I'm sure I'll be adding things over the next few months. Meentime if you or anyone you know wants to trade links let me have details.