Minima -A general coverage transceiver

From the designer of the BITX transceiver: a multiband SSB radio built from common parts with clever use of a microcontroller. The mixer design is particularly neat.

to amateur amplifier electronics hf lpf microcontroller mixer radio ssb transceiver ... on 22 March 2015

Filters - OpenRadioMiniconf

Building HF transmitter filters using air-cored coils, wound on a pencil. This is surprisingly effective!

to amateur coil electronics filter hf inductor lpf radio transmitter ... on 14 March 2015

Low Pass Filter kit

Kits for the GQRP LPF designs, £2.50 per band. Neat.

to electronics gqrp lpf qrp radio shopping ... on 07 September 2013

Harmonic suppression

6m LPF.

to 6m electronics filter lpf radio ... on 25 June 2011

GQRP Club - Low Power Amateur Radio

The GQRP guide to low-pass filter design. I need to order some bigger toroids.

to electronics filter ham lpf radio ... on 02 April 2011

HF Projects - Low Pass Filters

I'm awfully tempted by this multiband LPF kit -- it's not much more expensive than buying the bits separately would be, and it does exactly what I'm after.

to electronics kits lpf radio shopping ... on 27 February 2011

Genesis G59 Software Defined Radio Transceiver SDR QRP

Power amp with integrated low pass filters.

to amplifier filter ham lpf radio ... on 31 January 2011