OH7SV Matti Hohtola Ham Projectspop
- The most modern QRP transceiver in 2004,Direct Conversion HF Transceiver with DDS LO,
50 ohm to 200 ohm HF wide band transformers,
Wilkinson splitter for RX measurements,
Windom baluns 2001/2004,
Ferrite rod antenna for 80 meter, Magnetic Loop Antenna for 80 m, Mascot Switched PSU 9320 modification to 8A peak current, 150W MOSFET linear amplifier for 80m, 80 m HF SSB/CW Transceiver
- DL4YHF's Audio Spectrum Analyser Spectrum Lab or Speclab started as a simple FFT program running under DOS a long time ago, but it is now a specialized audio analyzer, filter, frequency converter, hum filter, data logger and more.
Can be used for MTHELL QRSS, DFCW, PSK, MSK, Castle
- Offer PC based virtual instrument for electronics enthusiasts, students and professionals, including full-fledged sound card real time Oscilloscope, Spectrum Analyzer and Signal Generator.
Tube Amplifier data and tech info
- Source of common model manuals and amateur help on amplifier problems for the amateur bands, Discussion of vacuum tube amplifiers. Technical information and discussion of obselete tube replacement.
144 MHz preamplifier with BF981
- Design of a preamplifier for 144 MHz with 1 dB NF and 23 dB gain using BF981. This amplifier is using a low cost silicon MOSFET (BF981 from Philips) to give more than 20 dB gain with around 1 dB noise figure on 2 meter.
U301 FET preamplifier
- This FET preamplifier has been around for almost 25 years. It is extremely reliable and can handle several watts directly into either the input or the output without failure.
23 cm GaAs FET preamplifier
- On 23cm the best way to obtain a good RX-sensitivity is to use a GaAs-FET in the front-end, since these devices show very low noise figures.
Receive only processing equipment
- One of our most popular products, receiving preamplifiers are used for achieving top signal band performance in competition operating, low noise longwave reception, repeater applications into the UHF region, or lab use