Electronics and Technical resources from vu3dxr
MXR Dyna Comp can be used as an audio compressor in SSB Amateur transceivers. The MXR Dyna Comp is a guitar effects pedal designed specifically for electric guitar. While it is a compressor, it wouldn’t be ideal for use in SSB transceivers for a few reasons: Impedance: Guitar pedals have a much higher input impedance …
Dynamic speech compressor or simply audio compression is an audio signal processing operation that reduces the volume of loud sounds or amplifies quiet sounds, therefore reducing or compressing an audio signal’s dynamic range. Compression is commonly used in sound recording and reproduction, broadcasting, hearing aid, live sound reinforcement, and in some instrument amplifiers. There are …
One watt AM transmitter This is a simple two stage transistor ‘one watt AM transmitter’ for the HF band which gives around 1 watt in output. You can use easily available transistors like BD139, SL100, 2N3866, 2N2219 or a 2N3553 in the final stage. The output with transistor 2N3553 is approx. 1.8 watt @ 12 …
Amateur Radio – End fed Halfwave antenna – Web resources and links An end-fed half-wave (EFHW) antenna is a type of radio antenna that is a half-wavelength long and has its feed point at one end. This makes it a very simple and compact antenna, and it is often used for portable or temporary applications. …
The Really cheap audio compressor circuit diagram from www.freestompboxes.org is a simple, yet effective compressor circuit that can be built with a handful of cheap components. The circuit consists of two op-amps, two LEDs, a LDR, a few resistors, and a capacitor. The first op-amp (U1) is configured as a unity gain amplifier. The input …
Multiband Half wave end fed antenna The end fed half wave antenna is an attractive option for many radio amateurs as it is able to provide multiband operation without the use of traps or stubs whilst occupying a minimum amount of space. A broad-band matching network is typically used to transform the high impedance of …
VK3YE’s AGC circuit for ubitx An ubitx AGC board is a circuit board that can be installed in a ubitx transceiver to provide automatic gain control (AGC). AGC is a feature that automatically adjusts the gain of the transceiver’s amplifier to maintain a constant audio output level, regardless of the strength of …
This loop antenna is based on one published in one of back issues of sprat by DL1HCU. It worked well with QRP power from 20-10 metres, including WARC bands. The tuning capacitor is twin gang type salvaged from old radio.