Another hobby of mine is electronics design, I build useful gadgets mostly for my own personal use.
    I might as well post some projects here, perhaps someone will find one useful.
    All schematics and PCB layouts are made with Eagle , the freeware version of eagle is able to view all schematics without restrictions.

    Do you need special purpose filters, pre-amplifiers or line-amplifiers? (0-3GHz)
    If you need PCB prototype boards etched, or electronic gadgets designed.
 

    0-30MHz MAX038 signal generator with LCD frequency counter. Original MAX038 schematic is basically copied from David L. Jones .
    One modification not shown on my schematic is that instead of the 22pF cap. at the range selection, I've removed it and soldered   a 10pF cap directly onto legs 5 and GND since the cable
    to the switch had alot of capacitance itself. This also made it somewhat stable up to about 32MHz.
    The LCD counter is switchable between internal measuring and bnc/sma jacks in the front panel, it's also remarkably accurate for such a simple design,
    calibrating it at max frequency with the trim-capacitor it was close to +/-10Hz over the entire scale of 0.3kHz to 35MHz, most impressive for a single
    4MHz PIC16F84, and this schematics was copied from a HamRadioIndia project, just some small changes like removing the swithces which aren't useful in my design, and the addition of a
    100pF capacitor between the LCD's enable and GND, for some reason the pic hangs after a few seconds without this capacitor.
 

    LCD counter schematic , PCB and HEX file for 1x16LCD (this source code was hard to find since
    almost all was designed for 2x16 displays).
    Main MAX038 oscillator schematic , PCB.
    Voltage regulator schematic , PCB. This PCB was unneccessary large due to that I did what size the heatsinks would be. It's fed with 24vdc.
    Amplifier board with 0-5v output level not finished yet.

    Audio preamp using 2 OPA27 opamps, I added a 50kHz lowpassfilter on the input to make it suitable for wefax use.
    The Soundblaster Live line-in needs alot more juice than the older soundblaster series so I had to make a litte preamp before the soundcard.
    Schematic , PCB , FilterPlot

    Icom CI-V adapter that fits inside a d-sub.
    Schematic , PCB
 

    AD595 temperature sensor and setpoint controller, 10mV/degree input on pin8, ie 1V=100degrees.
    Schematic , PCB

    One of the current project is a frequency synthesizer to replace crystals in Drake receivers, to make them cover all avaible bands without the need of any crystals.
    Built on a micro, PLL, and VCO following the Hageman design, but with my own modifications, since I'm redrawing the entire schematics and PCB to suite my own stock of components.
    There are some minor glitches that I need to correct, but basically it's working!








 

    Service Manuals and Schematics

    I haven't opened all files but there should be NO PASSWORDS and it's all FREE - no charge at all,
    it something would happen to be passworded - let me know.... we hobbyists need to stick together :-)

    As the years go by, manuals and software are getting more difficult to find.
    Therefor I've got the habit of collecting all useful manuals I find, the archives are several gigs so I won't put all of them here, only a few select ones,
    however - if there is a manual you can't find just contact me and I'll check if I got it.
    The archives do not contain just amateur radio manuals, service manuals and schematics, it also contain alot on electronic measurement equipment as well,
    oscilloscopes, curve tracers, power meters, voltmeters, multimeters, and alot of other equipment!

    NEWS! I'm currently building an extensive manual/schematics library, the idea was to gather as many manuals - servicemanuals - and schematics as possible,
    if you're into radios or electronics equipment you might already know how hard it can be to find this stuff for older equipment.
    Currently the library is 15gig but I'm looking for more, if you have anything you want to add - or just tip me where to find more - please mail me ( greger@rfelektronik.se )
    Not just Tektronix , Fluke , Icom , Philips , AVO , Collins , Drake , Cushcraft , Gould , Hammarlund , Harris , Heathkit
    HP , Kenwood , Lafayett , Marconi , National , Philips , RCA , Sony , Pioneer , WaveTek , Yaesu , but also alot less common makes...

    MANUAL / SCHEMATICS LIBRARY   <<<CLICK HERE - I put them all on my other site.


    PLEASE do not leech every manual just because it's good to have - this is kept on my DSL line at home, I'd rater burnd a dvd and mail it to you :-)

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