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 :-)