The amazing Boys' books of Radio and Electronics by Alfred Morgan!

The amazing website of Pieter Hooijmans

www.maximus-randd.com Had the great pleasure of visiting this informative website by the man who was designing RF tuners in Philips. And excellent account in many parts on the history of TV tuners in Philips from electronic valves ie electron tubes to Germanium transistors to silicon transistors to ICs. It is funny I was trying to find more answers for years on audio, radio papers. On this TV history one can even read what makes the PCC88 different internaly , an excellent description on how the cascode configuration operates and only the 1st part has been partly read yet.

Visiting Smartkit shop

Had the pleasure of meeting Daniel. Open minded with passion for electronic kits since a child,RF and AF. He showed me his TDA7000 FM radio. Fan of electron tubes too. He narated how the sound engineer of a live venue explained that you have to do it wrong now so that it comes correct sounding when the audience arrives due to the sound absorption of humans. He was briefed into some Pleiades battery powered preamps such as the Pleiades V6, the Pleiades (R,L) gentle slope low cut microphone filter, Pleiades Electra II, the Jean Hiraga, Maison d' Audiophile 2SK170 Le Passific MM phone low noise brilliant sounding preamplifier. Daniel is organised. I had the pleasure of getting a 300 in one electronic lab and a sample of Smartkit 1038N which may be great as a front end AM radio frequency amplifier or even a microphone pre pre amplifier.

AD1862 DAC IC directly connected to OPA541 power amplifier opamp

At your risk. Loudspeakers will be possibly damaged if the volume potentiometer in the negative feedback loop of the amplifier open-circuits. Have the pleasure of meeting again with Panos. He is driving his speakers in an impressing way with the signal path shown in the title. Just 2 ICs connected together, doing away with many op-amps normally found in a DAC, (digital to analog converter unit). The only op amp conected directly to the current output of the OPA541 IC is a power amplifier in itself, impressively directly driving, loudly with huge bass the speaker(s). Panos also brought to my attention the Sanyo LA6510 portable audio equipment power amp IC and the UPC2500D car power amplifier IC operating at single rail 12V. Panos was brief on one transistor (electrons flowing all the time, ie class A operation) power amps such as the Pleiades 2N3055, a one transistor radio found on youtube etc. We discused a bit line array full range column speakers.

melodybook

SHowing on the piano how great melodies with harmony are played. Initially conceived as the Melody book but some examples can be seen, heard on excellent Vicky Moriton chanel, Vicky is constantly improving as a producer.

How does the one transistor FM receiver operate?

This post may be wrong, the 1946 paper on locked in oscillator refered to on Television Engineering - Fink has not been read yet. The L, C reactance, LCR equations describing steady state ie after transient has decayed. Pehaps the most scientific method to undersatnd is taking a bouncing ball in our hands, play and examine its behaviour. The ball is a great analog computer, nature itself. We excite a system, firstly it is doing its natural it follows the forced oscillation. FOr example we clap our hand near a piano with the sutain pedal depressed, all strings vibrate excited by thisimpulse , almost delta function. On the so called locked in detector we havd to it from the transient point of view., rather than steady state. FM modulation is done by a music signal whiich is transient in nature. On the one transistor FM receiverthe received FM siugnal tries at any time to change the current through the osc L coil (part of LC). By nature inductance (analogous to mass) reacts to the change at any time and it produces an EMF (force) VOLTAGE.tHIS IS THE MUSIC SIGNAL WE GET BACK DEMODULATED. Similar to bouncing a basket ball between our hand and the floor. It has it natural osc frequency.If at any time we try to cjange that natural frequency The mass of the ball reacts (newton's 1st law), we get EMF ie force , we feel it on our hand.As we may try to descrese the frequency, same thing but force is no negative. We get our signal back, amplitude variations. Similarly to playing with a swing or a pendulum.