Resonances From Aether Days: Vintage Radio Equipment

Table of Content

General Culture Issues

• Historical Framework
• SSB Reception
• Radioteletype (RTTY)
• Mechanical Filters
• R-390A
• Filters
• 51S-1 Mechanical Filters
• Sensitivity

Collins Radio Company

• A Great Man, a Great Brand
• We Could Stop Here
• Great Products

The Roots of the Tree

• AN/ART-13 Transmitter
• (R)Evolutions: Autotune
• (R)Evolutions: PTO
• R-91/ARC-2 RX / TX

Collins 51J Receivers

• Introduction
• The Data Age Begins
• Description
• The Magic of Tubes
• A Linear Scale

Mechanical Filters

• 51J-4 Top View
• 51J-4 Bottom View
• Competition

R-390A/URR

• R-390A, His Majesty
• Better Than The Best
• The R-390/URR
• The R-390A/URR
• 1967 EAC R-390A/URR
• Mona Lisa Replicas
• Collins "First Order"
• 1954 "First Contract” R-390A/URR
• The R-390A Today
• R-390A Information
• A Few References
• R-390A in Short
• Innovations
• The Value of a Counter
• Mechanical Filters
• Modular!
• IF Subchassis
• An Empty Mainframe
• Mainframe Top View
• Mainframe Bottom View
• R-390A A-Side
• R-390A B-Side
• The RF Assembly
• The RF Subchassis

Table of Content (cont'd)

• Tuning System
• Gear Box
• AF Subchassis
• Temperature & Stability
• The Great Radio Massacre
• Using the R-390A for SSB
• Some Practical Suggestions
• Looking Inside the R-390A
• R-648 A Flying R-390
• R-725 A Special R-390
• “Inspire” by the R-390s
• A Few Restoration Tip
• R-390A Sensitivity
• A Never Ending Theme
• Conclusions

AN/GRC-19

• New Equipment
• GRC-19 History
• Common Characteristics

T-195 Transmitter

• Silence, please...
• The Strength of Innovation
• Overview
• Construction Quality
• No Space is Wasted
• Mainframe
• Exciter
• RF Power Amplifier
• Antenna Capacitor
• Antenna Inductor
• Output Capacitor
• Servo Amplifiers
• Discriminator
• Servo Amplifiers
• Modulator
• Positioning Secrets
• Positioning Recap
• Antenna Matching
• Feeding the Monster
• Restoration Story

Underrated

• RT-66/GRC (67, 68)
• RT-67/GRC
• Right View
• Block Diagram
• RT-66/GRC
• RT-67/GRC
• Top View
• General Architecture
• RT-68/GRC
• IF Chassis
• Wiring Side
• Mechanics
• PP-112 Power Supply Unit
• Wonderful Labels!
• R-108/GRC Receiver
• Specifications
• RT-70 Receiver/Transmitter
• To Work Inside A Tank
• RT-70 Specifications
• RT-70A Architecture

Some WW-2 Equipment

• First Love Is Never Forgotten
• The WS N°19
• R-107 The Sensitive Ugly
• BC-348, an Airborne Receiver
• BC-348
• R-44/ARR-5 Receiver
• R-45/ARR-7 Receiver
• Human Interfaces

German Equipment

• Not Worse Indeed

Siemens E309 Receiver

• A Great Brand
• Siemens E309
• Sprechen Sie Deutsch?
• Still Single
• B-Side
• Oscillator & Filtering
• Filters Check-up
• Tuning Dials
• Electronic Nonius

Competition

• Distant Drums
• German Precision

Siemens E311 Receiver

• Introduction
• Better Than Ever
• Some Comparisons
• Main Specs
• Modular
• Multi Modality
• Documentation
• Receiver Versions
• The Journey of the Signal
• RF Sections
• Intermediate Frequency Stages
• Filters
• A Road Test
• The Phantom Filter
• Detectors
• Audio Frequency Circuits
• An Ante-Litteram PLL
• How Does it Operate?
• Complementary Equipment
• Conclusions

Telefunken E863 Receiver

• Introduction
• The Opportunity
• Its First Words
• A First Road Test
• Technology Canned
• What Else Is Striking?
• Nixies, Come Again?
• Telefunken & the E863
• What Is BWB?
• Modular
• Key Points
• RF Stages
• Modern PLL Frequency Synthesis
• German Gears
• Frequency Display
• IF Stage
• Mechanical Filters
• IF Amplifier
• Decoders & AGC
• The J2 Instrument

More On the Front Panel

• Audio Amplifiers
• Power Supply
• Voltage Regulation
• The "Smoother"
• Thermostats
• Structure
• The Front Frame
• Upper Chassis From The Rear
• A World Of Interfaces
• The Upper Chassis
• seen from Below
• Upper Chassis From Below
• Frequency Control
• The Accessories Box Set
• Measurements
• So Beautiful
• Conclusions

Racal RA.17 Et Al.

• Racal RA.17, David vs. Goliath
• Space Wasters
• Nudity
• Seen From Below
• Geloso G4/216
• Allocchio Bacchini AC-18

The Silent Symphony of Radio Waves

Invisible, weightless, and swift as thought, radio waves swept across the void– a whisper through the ether, unlocking the miracle of human connection.

From the first spark across a wire to voices leaping continents, they gave us more than sound- they gave us reach, binding hearts and minds across oceans and time zones.

With every broadcast, a bridge; with every signal, a step closer. Music found ears it never dreamed of, laughter and learning traveled where no road could lead.

Friendships bloomed in static and Morse, hope flew on frequencies in the darkest nights.

These waves, unseen yet ever present, carry not just data, but dreams– and in their rhythm, humanity found its voice.