Service List

Project List


Other Material

Related Links


LTspice (Free) (Recommended)

Very good free Spice3 based circuit simulator from Linear Technology, with a vast selection of models specifically relating to Linear Technologies, linear and SMPS regulators. The models also include test benches. I have used the models with success to assist in development of an LT1249 based 1.5kW power factor correction circuit and a corresponding voltage-mode, half-bridge converter. I have also used it for some low frequency (to 27 MHz) E-class amplifier design simulations that were originally in Orcad (Cadence) Pspice. The GUI takes a bit of getting used to but is fine after a while. The plotting and postprocessing functions (cursor measurement , FFT etc) are VERY GOOD. I think that there is now also an interface between LTspice and Eagle.

NGspice (Free –open source)

Capable Spice3 based simulator. Includes Xspice functionality (but has to be flagged for some installations). Note: seemed it seemed to include the Xspice option as default when installing on windows. I've only really used this in the net list mode (i.e. with no GUI). The PLL Xspice examples seem to work well there are some other useful examples for RF applications. There are a number of links to GUI front-ends on the NGspice site here. There are also some examples of linking KiCad to NGspice. I've tried out Oscad (based on KiCad), found it non-intuitive, but didn't really spend that much time on it, and I think there are some good tutorials. CppSim is an excellent system simulator that also incorporates NGspice.

CppSim (Free) (Recommended)

This should really be included in system and RF simulator categories as well. A TRULY GOOD system level simulator, included in this section as it includes NGspice. Ive  used  it a number of times for general frequency-synthesizer and up-converter system level simulations. The website for CppSim contains some excellent papers and tutorial material.

B2SPICE (Commercial-but with useful trial versions) (Recommended)

This is a link to Beige Bag Software the creators of the B2SPICE family of SPICE based simulation tools. The simulator front end is easy and intuitive to use (making it an ideal tool for educational purposes) and the full versions of the software have powerful features. I have developed a lot of educational material using the demo versions (ADV4 Lite). One useful feature is the support of Xspice models for behavioral modeling.

Orcad Pspice (Cadence) (Commercial but with useful trial version on this page)

There should be a trail version of Pspice somewhere here. I have used this a lot in the past for general  electronic and low frequency RF simulation. I found that it was a very capable simulator. Not sure what the limitations are now regarding the trial versions, but I seem to remember that they were useful.

Dolphin Smash (Commercial — Think there may be useful trial version)

Very good mixed-mode simulator. (I have used this a number of years ago and am not familiar with the current status). Includes Spice, VHDL, VHDL-AMS and has good plotting capabilities. I mainly used this, for synthesizer design and analysis (VHDL, behavioral and Spice), with a netlist interface, . It seemed to work very well and have good plotting capabilities. Used it occasionally in conjunction with Cadence for schematic capture. A graphical interface exists and is shown here.

DesignSpark PCB (Free)

I've tried this in the past for PCB design and it seemed OK. I've seen reports that it now has a simulation interface, although I haven't used it yet.

Online spice based circuit simulators

There are a number of online based circuit simulators. Some are linked below. Many are in developmental stages but look promising. The main criticism with some, is the ability to extract and post process simulation results .

PartSim (Free)

I have tried out some of the examples with this simulator. The schematic capture front-end looks V.good and is easy to use.  It could do with more simulation and post processing options. As far as I know this is being planned / under development. Potentially could be a very good simulator as it evolves.

NGSPICE online (Free)

Netlist only online version of the NGspice simulator. Have tried a few times with basic circuits and the outputs look OK at lest for transient analyses. Seems to lack post processing functionality (although there may be ways to do this that I’m not aware of). Tried with FFT and linearize commands in the plot dialogue, but could only get the transient response plots.

Circuitlab (Commercial-free student educator versions)

I've only looked at the GUI for this. It looks to be very good, however, you have to pay a subscription fee and I am not totally sure of the categories as yet and what limits there are on the trial versions.

WEBENCH® Electrical Simulator (Free)

Simulator from Texas Instruments. I haven't used this. from the text on the website it seems to use the Tina circuit simulator for simulating TI’s SMPS and PSU components. (Similar to LTspice ?). I’m not sure if you can use it for other Spice circuit simulations. I’m guessing that if it is based on the Tina simulator it will work well.

Other free and commercial Spice simulators

Tina-Ti (Free)

Spice based analog simulation program from Texas instruments used this a while ago, and it seemed to work vey well. Lots of simulation models and test benches are available form the site.

ADIsimPE powered by SIMetrix/SIMPLIS (Free)

Free version of  SIMetrix for Analog devices parts. Haven't tried this yet but the manual looks promising and it looks like the simulator would be useful for PLL circuits. Page give links to example circuits. AD also have general Spice model links here.


Analog FastSpice (Commercial)

Should be included in the RF simulators as well. Looks very good, but expensive.


Related Links


I have found the following links useful in the past. Hopefully, they will be of use to you. I have tried to categorize but there is inevitably some overlap of functionality. I've also tried to concentrate on free tools or tools with a good trial version.



PCBPOOL pcb manufacturing services. I have used these for manufacture of various prototypes for FR4 based substrates. I have found the service to be very good. Good links to demo PCB software are included on the site. The site now also includes Label / front panel design services and mechanical prototyping (3d printing, machining etc) services. NEED to be carful that you ensure that the layer stackups and dielectrics are consistent when transition from the “prototype-series” to larger volumes. I think that FR4 and aluminum substrates are the only options at the moment. The site also provides population services.

Quick-teck PCB

The site provides PCB manufacturing and population services. I have used them in the past for some clients boards and they seem to provide a good quality service. The main focus is for FR4 substrates, and again you have to be carful to check and specify the layer stackups for boards that require impedance controlled transmission lines. I have contacted them in the past asking about high-frequency dielectric boards and they said they could supply them on special request.


I have a number of other contacts for.

Þ Board manufacture using high-frequency laminates.

Þ General PCB population. Through-hole and surface-mount, exposed pad etc.

Þ mmWave manufacture—some contacts for wire bonding services and precision machining.

Þ Contacts for general CAD and CNC machining.



To contact me :

Phone:  Lancs 825064

E-mail: martin_AT_mjb-rfelectronics-synthesis_DOT_com

Software / Service Links


General Component / Material Supplier Links

QUCS (Quite Universal Circuit Simulator) (Free) (Recommended)

A free and very useful RF circuit simulator. Supports linear (s-param, AC), transient, and harmonic balance ? simulations. It also includes some useful tuning and filter design wizards. Allows simulation of distributed components, s-parameters, etc. Microstrip and S-parameter simulations seem to correspond  very well with other free  and very expensive commercial tools. In the past I've tried comparing some of the simulation results for vendor supplied s-parameters blocks against some commercial tools and have got some very favorable results. The site seems to mention that Harmonic balance simulation is still under development. I've tried the diode example out (directly and with altered parameters) and managed to get believable results and results that correspond to high-end commercial simulators. The QUCs package also now has support for Verilog and includes an Octave interface. There are some good examples and academic papers online explaining the use of Qucs for modeling of advanced RF systems. Some of the papers also provide comparisons to commercial tools. The main drawback is lack of extensive libraries for RF components.

QucsStudio (Free)

This has evolved out of Qucs (see dialogue on the link), but mentions that it doesn't use the same simulation engine as Qucs. It seems very good and some of the examples look interesting. I really need to investigate this further.

CppSim (Free) (Recommended)

See description above.

AppCad  (Free ) (Agilent / HP) (Recommended)

A selection of useful tools for RF / Microwave design.

RFSim99 (Free)

A useful linear RF circuit analyzer. Note:  this no longer seems to work directly with windows 7 and above. However this new link provides details of how to fix it. QUCS is possibly now of more use.

Vipec (Free)

Linear RF circuit simulator. I have only tried this for simple S-parameters, but it seems to work well and has a good user interface and good output capabilities.

S-Parameter Explorer V1 (Free)

Useful tool for S-Parameter conversions and plotting. The parent website also seems to have some other useful calculators.

fREEDA (Free)

General purpose simulator that includes harmonic balance analyses. I Need to try this out.

HBfree (Free)

Harmonic balance simulator. Used this a number of years ago and it seemed to give OK results.

TX-LINE (Free)(Recommended)

AWR’s downloadable transmission line calculator (Requires registration). A very useful application which seems to provide consistent results for CPW (Co-planar waveguide). Thoroughly recommended.

Online Microstrip and Stripline calculator (Free)

A useful online trace impedance calculator tool from the University of Missouri-Rolla EMC laboratory.

Eeweb online tools (Free)

The site provides a good selection of online tools and calculators. It includes a section of PCB impedance calculators.  I haven't used all of these yet, but they look very good.

SiversIMA online RF calculators (Free) (Recommended)

Lots of useful calculators for RF circuit design, link budget etc. I've used some of the calculators in the past and they work very well. The parent site also has a number of good RF, Microwave, mmWave products. From past experience the prices seem to be reasonable as well.

 Aplac (Commercial)

This has now been taken over by AWR and is incorporated into Microwave Office. A very good harmonic balance and transient RF simulator. I have used the commercial and student version a number of years ago. Unfortunately you can no longer obtain the student version, but you can request a trial of Microwave Office that includes Aplac.

Ansoft Designer SV (Commercial)

Very good all round circuit and system design package for RF and microwave systems available from Ansys. The link is actually for the full version (which may now be Ansys Simplorer). In the past there used to be a student version (SV) available. The student version would allow linear system design using S-parameters, and also included some very good synthesis tools. This is still available on the web along with some excellent tutorials. The Ansys site also includes the 3D EM simulator HFSS.

Agilent ADS, Genesys, etc (Commercial)

Very capable sets of RF / microwave circuit and system design software. I have used ADS in the past with good results. I’m guessing that there have been a number of improvements. ADS is costly and feature rich, but there are good short term lease options. Trial versions and student versions are also available for non-commercial try-outs. Best to look at the Agilent website for the features of the software. The contacts for trial versions etc, seem very helpful.

AWR—Microwave Office (Commercial)

All of the comments for the last entry apply to this. I've tried out some of the trial versions in the past and the software seemed to work very well. 

RF / Electronic websites

I've mainly used Orcad (Cadence PSD) and Protel (now Altium in the past) for commercial projects. However, I've recently been looking at Kicad and DesignSpark, that both look very good and seem to work very well, especially considering that they are free.


Note that some of the design packages mentioned below also include options for interfacing directly to circuit simulators. There are also a few tutorials online for interfacing Kicad to NGspice.


Kicad (Free-Open source) (Recommended)

Very good open source software for schematic capture and PCB layout. I seem to remember that there used to be some layout examples for PCB trace patterns useful for RF / microwave applications.

DesignSpark PCB (Free)

I tried this out a couple of years ago for some designs, and it seemed very good. There now seem to be a lot more tutorials and information on the parent website. There are also some free mechanical CAD packages on the website.

Eagle (Commercial—but with useful free version for non-profit applications)

I've used the free version lightly just to view files and do some simple modifications e.g. Arduino files etc. It looks very good , and I've got contacts who use it al the time and would recommend it. As I’m more familiar with Orcad, Protel, Kicad etc, I've tended to find that the key combinations and shortcuts take a bit of getting used to, but as all my libraries are for other packages the incentive isn't really there.

Target 3001 (Commercial with OK free version)

PCBPool have an unlimited  version that can just be used with their PCB fabrication service. I've used this in the past for layout and simulations and it seems to work well.

Cadence Orcad Solutions (Commercial—demo available on request)

Very capable PCB schematic capture and PCB design software. Also as a good Spice simulator available. I've used this a lot in the past with older versions (up to version 14), and also looked at the newer demos. I've also used the Cadence IC design suites and will put these in a list with other open source offerings sometime.

Altium (was Protel) (Commercial)

Used this a long while ago when it was Protel (just before it changed). It seemed to work very well then, and I am guessing it is still a very good design package. I haven't managed to investigate the newer demo versions yet.

Proteus (Commercial — reasonable pricing options)

I've used this a few years ago, and found it to be a very good piece of software. It was intuitive to use and had some good tutorials. The price breaks seem to be very reasonable as well.

Magic VLSI Design Software (Free)

Integrated circuit layout software with compatibility with MOSIS technology files. Tutorila are included for development of Process design kits for use in Magic. I've used this a number of years ago mainly to look at cell layouts of simple circuits , at the time I also had access to the Cadence IC design package. The software seemed to work well once the technology files were set up correctly.

Electric VLSI design system (Free)

Integrated circuit layout software. I've used this a number of years ago in a similar manner to that outlined in the above entry. I seem to remember that this worked very well when set up (used to only be able to compile it from the source). Also seem to remember that it had an option for PCB layout and simulations. Now that distribution is as a windows binary I will try it out again at some point.

PCBWeb (online PCB layout — free to use)

This looks very good, but I have to get round to trying it out.



A very good site providing information on all aspects of RF design and products. There are good links to various RF calculators and other technical resources.


Lots of useful practical data and tools relating to microwave engineering. Includes good stripline calculators.

Microwave Journal

Online version of the Microwave Journal. Excellent archives containing papers relating to Microwave system and circuit design.


This site provides some very useful links to schematics and reference designs from various manufacturers. The site provides a concise and comprehensive diagrammatic description of a circuit. Schematics.com allows users to connect and share designs and ideas in a like-minded community.



An excellent website with links to a variety of RF engineering topics.


American Amateur Radio Relay League. Main American organization for Amateur Radio. Some good links to useful technical articles.


Radio Society of Great Britain. Main UK organization for Amateur Radio. Some useful books available.


The site contains lots of links to material that is useful for RF and communications engineering. The site also contains links to various types of RF and electronics software. A good site.

RF Globalnet

More of a commercial / advertisement site now (the site used to have lots of links to free tools etc). However, still a useful site with some useful information for RF and Microwave.


Good site with lots of good general engineering links. Some good engineering tools are included on the site.


Another interesting site with lots of  useful articles on electronics engineering.

Electronics Weekly

Another interesting site with lots of  useful articles on electronics engineering and emerging trends.

UK Microwave Group

Lots of good links on this site relating to microwave applications.

Spread Spectrum Scene

A good site with a lot of links to tools and article useful for RF and communications engineering.

UK EMC information

Very good site with lots of information relating to EMC testing and issues.


UK’s Institute of Engineering and Technology (Formerly IEE—Institute of  Electrical Engineers). Very good site with lots of resources, especially if you are a member. Various sectors and special interest groups for RF, Microwave, IC design.


Institute of Electrical and Electronic Engineers. Very good site with lots of resources and some interesting specialist journals and societies. A number of good resources are available to members.

IEEE Computer society

Society of the IEEE. Definitely worth joining as there are lots of resources and online seminars (some free) on RF communications related subjects. 

IEEE Solid state circuits society

The journal has lots of interesting papers on RF integrated circuit design.


Electronics and Telecommunications research institute Korea. The journal frequently includes papers that have an interesting RF or microwave engineering focus. In the past I have assisted as a reviewer for this Journal.

IEEE Industrial Electronics Society

Good journal that some times has papers relating to synchronization and RF applications. In the past I have assisted as a reviewer for the journal.

IET Microwaves, Antennas and Propagation

Journal has very good contemporary papers.

IET Circuits, Devices and Systems

Journal has very good contemporary papers.

IEEE Microwave Theory and Techniques society

Good society with good journal articles.

Farnell In One

Good comprehensive source of electronic components. Good range of IC’s, DDS etc.


Good comprehensive source of electronic components. Good range of IC’s


Good comprehensive source of electronic components. Some Murata and Toko components in small quantities. Shipping charge required to UK.


Very comprehensive source of components, with good service. They stock some Triquint parts.



Good comprehensive source of electronic components. Very useful for smaller discrete order quantities.


Good comprehensive source of electronic components. Range not as extensive as the above though for IC’s , discrete and passives.


Excellent supplier of oscillator and SAW filter products. Very good service.

JAB Electronic Components

Good source of  RF components. Includes toroids, Toko coils, silver coated copper wire, etc

Amidon Associates

Toroid cores, suitable for high power RF and switched mode power supplies. Useful data on site. Small volumes.


Vast array of off-the-shelf and customizable microwave components including horn antennas. Enquired for pricing / design in the past and had good rapid response and reasonable pricings.

Micro Metalsmiths (Now Sylatech)

Lots of very good micro and mmwave components on this site. Enquired in the past for pricings / design and test. Got good response and reasonable pricings.

Castle Microwave

Suppliers of RF and microwave components. Used them in the past for some amplifier components and they were very good.

Solid State Supplies

I've used these in the past . Service and communication from the agents was excellent. They now seem to have a very good linecard.

Richardson Microwave

Very good selection of RF and microwave components. I have used tem in the past via various clients and they provided a very good service.

JPR Electronics

Good comprehensive source of electronic components.



OEM businesses looking for wirewound and high precision resistors should look to the professionals at Riedon.


Dr. Martin John Burbidge

Electronics and RF, research, development and prototyping.

General Spice based circuit simulators

RF / microwave specific circuit simulators and support tools

EM / waveguide / antenna simulation software

Openems (Free) (Recommended)

Very very good 3D Electromagnetic simulator using the FDTD method. Uses Matlab or Octave for the interface. As I don't have access to a version of Matlab, I tried interfacing to Octave with success. The instructions were well set out and easy to understand Lots of good examples for Horn antennas etc. Tried modifying the rectangular horn example dimensions for 10GHz operation and the package seemed to work well. IT would be good if this could be interfaced to an open source RF simulator such as QUCS.

FEST3D (Commercial –but with very good trail versions) (Recommended)

Excellent software for the design and synthesis of waveguide structures. The full versions also allow multipactor analysis to be carried out. I have compared the synthesis results of this with some other tools and textbook examples and it gives very good results. Some examples of tests will be included on my ongoing project list page  I’m currently trying to find the time to use it more.

Sonnet (Commercial - Very useful “lite” version)(Recommended)

3D planar EM simulation software. Very useful for microstrip and stripline filter design also useful for patch antenna design. A lot of examples are included that can be run on the lite version.

4NEC2 (Free) (Recommended)

Very good antenna design and simulation software. Some examples are included for rectangular horn geometries, however you have to add an appropriate driven element for excitation. I tried this out in the past and seemed to get acceptable results.

emGine (Free)

I've tried this out in the past using the trial version, and it seemed to work well. The site seems to mention that there is an unlimited version available for non-commercial applications, but I haven't tried it out yet.

Feko and Antenna Magus (Commercial—but have some good trial versions)

Very good EM simulation and antenna simulation packages. I've tried the trial versions out in the past  and they seem to work very well.

MEEP (Free)

FDTD electromagnetic simulation software from MIT. I haven't used this yet, but there seem to be some good examples and tutorials for waveguide structures here.

Elmer (Free)

General purpose finite element modeling software. Haven't used this yet. There seem to be some good applications on the website.

MaxFem (Free)

General purpose finite element modeling software. Haven't used this yet. There seem to be some interesting application examples on the website.

WIPL-D (Commercial-but with good lite  pricing options)

Provides a good set of EM RF simulation software. Tried out the demo versions and they worked very well. Lots of  application examples are included on the website.

FreeEM3DS (Commercial but with good free cut down version)

Interesting software for EM simulation with some good examples. I have tried out the trial version briefly by modifying the Dielectric resonator examples. The software gave good results, however I need to tryout some more examples in the future.

Simulation Models—S-parameters and Spice

Spice models


Link includes RF transistor spice models, and also S-parameter models.

Central Semiconductor corp

Links to some low frequency RF transistor spice models.


High-frequency RF spice models and S-parameter models for Polyfet MOS and GaN transistors. The parent website also contains some useful links, application notes and tutorials.


Links to P-spice models for various transistors. RF transistor model links are below.


P-spice models for high-power, mainly HF RF switching transistors.  I've used the P-spice models directly for E-class and C-Class and AB class simulations and designs, and they seem to give good results. I have also adapted some of the models in the past for use in LTspice.

Fairchild semiconductor

Links to spice models for various devices. Has a link to some bipolar RF transistors. The MOSFETS section also has links to 2N7000 models.

ON Semiconductor

Link to spice models for various transistors, diodes and other devices.

International Rectifier

Link to various spice models for International Rectifier devices.


General links to spice models and S-parameters. Note most of the RF transistor links seem to provide ADS and Microsoft office kits. However, clicking on the top two links opens further links to S-parameter files.

NXP (Further links to RF wideband transistor spice models)

Further NXP links to spice models for wideband RF transistors at the bottom of the page.

AVAGO Technologies

Links to Design tools and models for RF and Microwave devices. Includes S-parameter and spice models.

Texas instruments

Links to TI’s general spice models.(Mainly OP-Amps) Also contains links to models and libraries specifically for use with TINA-TI.


Spice and S-parameter models for AVX capacitors. The parent site also includes some good online and downloadable tools to assist parts selection (see SpiCap 3.0).


Spice and S-parameter models for various RF and power inductors. Examples are provided on the page for Pspice and LTspice.

Maxim Semiconductors

Lots of links to spice simulation models for Maxim devices.

Diodes Incorporated

Lots of spice models for diodes, transistors, etc. A link is included to download the whole library.


Various links to Pspice models for operational amplifiers, video amplifiers, and buffers.

Linear Technology

LTspice (see spice links above) and spice model page.


Various spice and S-parameter models.


Various spice models. The site also has links to a tool to covert S-parameters to spice macro models.

S-parameter models

Online CD of S-parameters by G-Kraus

Excellent compilation of S-parameter files in one place.


S-parameter and impedance tool. Sofware to allow selection and extraction of S-parameters for Murata capacitors and inductors. The site also has links to various S-parameter files and spice files for other devices. The MURATA online design tool  “SimSurfing” also allows extaction of spice netlists.

Mini circuits

Lots of S-parameter files for specific circuits. You have to select the specific device and then select the S-parameters.


Lots of S-parameter files for specific circuits. You have to select the specific device and then select the “model data” file.


Lots of S-parameter files that are generally included in the product description page. Some of the S-parameter files are available on request. Now owned by Analog Devices.

RF micro devices

Lots of S-parameter files that are generally included in the product description page. Some of the S-parameter files are available on request.


Lots of S-parameter files that are generally included in the product description page. Some of the S-parameter files are available on request.


Lots of S-parameter files that are generally included in the product description page. Some of the S-parameter files are available on request.

American Technical Ceramics

S-parameter data for capacitors and inductors from ATC.

Thermal simulation tools

Note some of the software highlighted in the “EM / Waveguide / Antenna simulation software” section above, allows thermal simulations to be carried out. See “Elmer” and “MaxFEM”


THsim (Free)

Interesting thermal simulator that uses a spice engine for simulation. Tried this out a few times and it seems to give believable results.

Novelconcepts inc (Free)

A useful set of online tools for thermal calculations. I've used the “FORCED CONVECTION HEAT SINK THERMAL RESISTANCE” section a number of times, and it gives good results.

Lisa (Free 1300 node limit—can be unlocked)

Finite element analysis software, that has some examples and tutorials for thermal analysis. I haven't used this yet (only downloaded and looked at some of the examples), but it looks good on initial inspection. There seems to be lot of examples and tutorials on the website and the 1300 node limit for the free version appears to be useful . Also the unlocked versions look very reasonable.

General mathematical modeling software

GNU Octave (Free) (Recommended)

Mathematical software for numerical computation similar to Matlab. A number of good tutorials and toolboxes exist for communications and RF. The command line interface works OK if you have some familiarity with Matlab commands. Some simple Matlab *.m files will run in Octave, however many now have  dependencies on non-Octave functions. This software works well with Openems. Doesn’t include a time domain graphical simulator such as Simulink. However, in the past, I have found  CPPsim to work better for certain system simulations (i.e. PLL, SD, etc).  Extra Octave packages / toolboxes can be found here http://octave.sourceforge.net/ .

MATLAB (Commercial) (Recommended)

Very comprehensive numerical simulation software. Also has symbolic programming via Simulink. Lots of user added code for communications and RF applications. I seem to recall when I have purchased this software for companies, you have to select appropriate toolboxes for your applications.

Scilab (Free) (Recommended)

Numerical simulation software that also includes a Simulink like interface. Includes a Matlab to Scilab converters that work on some Matlab functions, and also includes examples of conversion of some Matlab syntax and functions for use in Scilab. Some communications toolboxes are available on Sourceforge.

ScicosLab / Scicos (Free) (Recommended)

I Think that this is a spin off from Scilab. Includes a graphical front-end similar to Simulink. There is also a useful communications systems blockset called Modnum.

Maxima CAS (Free) (Recommended)

Algebraic / symbolic mathematical programming. With good plotting capabilities.

Sage   (Free) (Recommended)

Algebraic / symbolic mathematical programming. With good plotting capabilities.

SMath Studio (Free) (Recommended)

Algebraic / symbolic mathematical programming. With good plotting capabilities. Very similar to Mathcad and Maple. I have used this in the past with good results and adapted some PLL modeling files from Mathcad. The old main website seems to be inactive, however files can be downloaded from the forum. Very good.

PCB layout software (some free IC layout tools at end)

Mechanical CAD software



FreeCad (Free—open source interface)

I don't tend to use mechanical CAD software a lot, but I've tried using this for some simple milled enclosures with and without additional finning and also some very simple split-block waveguide structures. It seemed to work very well and was OK to use after following the tutorials. Lots of good tutorials are included on the parent website.

Design Spark Mechanical (Free)

Only just noticed that this is available. It looks very good and I will have to try it out.

eMachineShop design software (Free)

Free software available on a machining service provider site. The software is designed to work with eMachineShop orders, but is also useful in its own right. Ive used it in the past to do simple / quick renderings of  enclosures.




PCB manufacturing, population and mechanical services

Further miscellaneous links

I have another website  that is related to electronics for renewable energy applications and products.  Its basically a spare time activity and gets updated as and when  www.ecopivotal.co.uk.

When I get the chance I plan to put some more links relating to mechanical engineering applications and Stirling engines here and on the other site.

RF and electronics test equipment:

Manuals / repair and GPIB tools


Links for various manuals mainly relating to RF test equipment. Note: Unless stated, most are free repositories


Excellent site with lots of links to test equipment manuals. The site also has interesting articles on test equipment repair. There is an excellent article on refurbishment of  the HP 8569B Spectrum analyzer rotary switches here.  I recently (Jan 2016) contacted Simon as I had a problem with the Sweep function above 2 MHz / div on an HP 8569B and thought I might need a new sweep generator board. I luckily managed to trace the problem to a faulty resistor after working through the service manuals. Simon gave some excellent feedback especially relating to replacement boards for the unit. Details of the sweep problem are outlined on Simons site here.


Another interesting site with lots of information on test equipment. The site has excellent links for electronics and RF test equipment manuals.


Hewlett Packard Archive. The page contains lots of links to manuals for older vintage HP test equipment. Further links are also provided on the page. Note that the home page for this site also contains links to old HP journals here. A lot of the older HP journals provide information that is still relevant in terms of microwave and RF testing.

Keysight (formerly Agilent)

Use the “Document library” link. The site now contains archives of some older and discontinued products. The parent site also contains excellent tutorials and app-notes relating to RF test and measurement procedures.

Keysight Links: Discontinued manuals (Mostly commercial)

Note: it mentions at the bottom of the page that the keysight library team may be able to provide older manuals. Possibly worthwhile checking the previous link in this list first though.

ManualsPlus (Commercial reasonably priced)

In the past I have purchased hard copies of manuals that I couldn't find online form this site (e.g. Marconi 2383 spectrum analyzer manual). I've just checked the site out (May 2016) and it has this message “As many of you may have heard, Manuals Plus is closing its doors. -We have made an agreement with The Internet Archive to donate our entire library to their collection. You can find information about them at (https://archive.org/about/)”. Hopefully, the archive.org site will have more manuals available in the future. I've had a quick look at the site and it seems to have  scanned copies of a number of more difficult to find manuals.


This is a general archive site. However, it also seems to contain lots test equipment manuals and articles on RF and electronics. For a general search try <Texts> => <Search> “test equipment manuals”, alternatively try to search for a specific manual . Also see the entry for ManualsPlus above.

The Boat Anchor Manual Archive

Good archive site with lots of links to older test equipment manuals.


Bird Technologies

Link to manual for the ubiquitous Model 43 wattmeter. The site also contains various excellent applications notes and calculators here and here.

Various good application notes and manuals can also be found on the following sites

Rohde & Schwarz



GPIB (General Purpose Instrument Bus)

Various GPIB links.

Prologix USB to GPIB adapter

Supplier of GPIB to USB (and Ethernet) converters. Note: I've used National instruments and Agilent GPIB IDE / PCI cards in the past  and  they have worked really well. I wanted a reasonably priced USB alternative so that I could use my laptop for GPIB transfers. The Prologix adapter seems to work very well.


KE5FX GPIB Toolkit

Lots of really excellent GPIB utilities on this website. I tend to use the 7470 plotting emulator a lot with an HP 8569B and it seems to work well.


Follow the page link for EZGPIB. A good GPIB biased programming environment with some excellent examples and utilities. The examples include an example DLL for use with Profilab. I've used this software in the past to interface to various equipment with good results (HP 8569B, Marconi 2383, HP54120B etc).

GPIB overview

A good general overview of GPIB hardware and operation from the KO4BB website.

EZGPIB and Prologix GPIB Adapter Overview

Another excellent overview of the Prologix GPIB adapter used with the EZGPIB programming environment.  The overview is provided on the Clifton Laboratories website This site also has some examples for using the KE5FX GPIB toolkit.