Archive for the ‘Building projects and kits’ Category:

2019-11-26 My Radio As A Kid

from FB Comment Nov 26 I inherited old tube radios, I never had a boy’s radio, still don’t today. But I got a 2 transistor SupereX kit that I built. It was a crystal set with an earphone amplifier. Didn’t work very good because I lived a few miles from an AM transmitter and until

(Read More…)

2019-11-15 Build A LED Tester

Big Clive’s YouTube video Ohhh nooo! After all the trouble Big Clive went to show us how a Joule Thief works, he *digressed* to using a 9V battery for his LED tester! Horrors! 😱😱😱 I built a Joule Thief with a socket like he used for the LED. But the JT must not be left

(Read More…)

2019-11-07 Audio Impedance Matching Box

I’ve often had to kloodge together an audio transformer, jacks and other stuff to make a medium impedance output match a low impedance headphone. But it turns into a mess of wires and parts dangling from a transformer. I thought about what I would do to make a box with the necessary stuff, like inputs,

(Read More…)

2019-10-12 RF Oscillator Won’t Make A Sine Wave, Only Sawtooth

I wanted to make an RF Oscillator that puts out a sinewave at about 734 kHz, which uses two convenient values, 100 uH coil and 470 pF capacitor. I used the toroid core with 16 turns of 30 AWG wire, with a tap at 4 turns then later 8 turns. I built the circuit in

(Read More…)

2019-09-30 RF Modulator

For the oscillator I used the Hartley oscillator circuit that is used in the Eico 330 signal generator. I didn’t need any of the range switches – I left that out. It used MPS6513 transistors which are cheap but very uncommon – I can’t remember ever seeing them in any schematics or in PC boards.

(Read More…)

2019-09-27 Phase Shift Oscillator For RF Signal Generator

2019-09-27 PSO I tack soldered the parts together for a PSO, and made modifications to get it go work at 500 Hz. My goal is to get a steady tone to use to amplitude modulate the RF signal generator that I have built (see this blog). The sine wave from this PSO is beautiful –

(Read More…)

2019-07-06 Earliest Audio Amplifiers I built

from FB group Building Transistor Radios July 6 Bill Korbak The early germanium alloy transistors didn’t have enough bandwidth for RF, they were only good for audio. That’s where I built my first amplifier, a three transistor audio amp on a PC board I etched in ferric chloride. I also built the power amplifier. It

(Read More…)

2019-06-12 Plug-in Coils Pros And Cons

from FB group Regenerative Radio… Jun 13 I’ve thought about using plug-in coils, but I’ve had experience with Grid dip meters and there are a few important issues that must be dealt with. One is, what happens to the unused coils when the equipment is not in use. They get separated from the equipment and

(Read More…)

2019-05-25 Books Insult Your Intelligence

from FB group Building Transistor Radios May 25 Loren Moline I don’t think the book insults your intelligence. The book itself is often written with subset of readers in mind such as beginner, professional, mathematics challenged, etc. It’s the failure of the book advertising to make that clear. I believe the book advertising hypes every

(Read More…)

2019-05-19 No Go Showboat

from FB group regenerative receiver initiative May 22 Henrik Stenstrom I would like to build something hollow state with all sorts of gizmos like in this photo, but all of it would be a no-go showboat, just for looks. I would put Amber or orange LEDs under the tubes to make them look like they’re

(Read More…)

© RustyBolt.Info/wordpress
CyberChimps