Dr. Greg Latta's
Electrical Engineering
and
Amateur Radio Pages

Welcome to my electrical engineering and amateur radio pages.
These are updated on a regular basis so I encourage you to stop back every so often.

Click on one of the links in the table
below or scroll down for more information:
Receivers	Transmitters	Amplifiers	Accessories	Miscellaneous and Academic
The AA8V 6x2 Superheterodyne Receiver	The W8EXI Wingfoot VFO Exciter	The AA8V 6AG7 QRP VFO Amplifier	AA8V Digital VFO For Vintage Transmitters	The AA8V Station
The 6x2C 30m/20m Receiving Converter	The AA8V 6CL6 One-Tube Transmitter	The AA8V 6146B Amplifier	Electronic T/R Switching and the Ameritron QSK-5	The Workshop at AA8V
The AA8V Twinplex Receiver	Johnson Viking Ranger Restoration and Circuit Descriptions	The AA8V Wingfoot 813 Amplifier	Using the LM-13 Frequency Meter as a VFO	Aluminum Chassis Construction
	Heathkit HW-101 Transceiver		An Automatic CW T/R System for Vintage Stations	A Study of Secondary Emission in Vacuum Tubes by Angela Meyers

**The AA8V Station**
The AA8V Station After many requests I have written web pages that will take you on a tour of my amateur radio station. The station features a modern transceiver, a vintage set of Drake Twins from 1965, a vintage station from 1955, and a large amount of homebrew equipment, including a homebrew 6-tube superheterodyne receiver.

**Miscellaneous**
The Workshop at AA8V I recently had a short time between projects and decided to take you on a photographic tour of my shop. The shop features an electronics shop, metal working machine shop, woodworking shop, photography area, and painting area all packed into a very tight space.

**Accessories**
An Automatic CW T/R System for Vintage Stations If you are a CW operator and use vintage or homebrew equipment then this unit is for you! It will give you they same convenience in T/R switching you enjoy with modern gear. Just touch the key and you go into transmit. Stop sending and you drop back into receive after an adjustable hold time. Features a sidetone generator and can key both positive and negative(grid block keyed) transmitters.	AA8V Digital VFO For Vintage Transmitters One of my most useful projects is a Digital VFO for Vintage Transmitters that I designed and now use with all of my tube and vintage transmitters. The web page greatly expands on my article that was published in the January, 2014 issue of QST magazine. The VFO provides modern frequency stability, digital readout, and operating convenience when using vintage or tube transmitters such as the my 6AG7 one tube amplifier/transmitter, my 6CL6 one-tube transmitter, the Eico 720, and the Johnson Viking Ranger.

**Receivers and Receiver Accessories**
The AA8V 6x2 Superheterodyne Receiver The 6x2 Superheterodyne Receiver, is a 6 tube superhet receiver for the 80 m and 40 m bands. The receiver is my pride and joy. It features a crystal filter for single signal CW reception, a crystal calibrator, and the ability to receive WWV at 5 MHz.	The AA8V Twinplex Receiver My most popular web page is perhaps the AA8V Twinplex Receiver. The Twinplex is a one-tube regenerative receiver well within the capabilities of any builder. It has been built by hams and experimenters throughout the world.
The AA8V 6x2C Crystal Controlled Receive Converter The 6x2C is a two tube crystal controlled converter designed to be used with the 6x2 superheterodyne receiver. It converts signals in the 30m and 20m bands to the 40m and 80m bands.The converter features an RF amplifier with a manual gain control. The 6x2C and 6x2 receiver together constitute a 4 band double conversion superheterodyne receiver.

**Transmitters and Transceivers**
The Johnson Viking Ranger One of my favorite projects was the restoration of a Johnson Viking Ranger. It is now fully restored and working hard on the air, both on CW and AM. It is a classic transmitter and I have taken a lot of time on the web pages to explain in intricate detail the operation of the transmitter. If you go to the schematic diagram page you can click on any section of the schematic diagram and read about that section of the circuit in great detail.	The Heathkit HW-101 The Heathkit HW-101 was one of the most ubiquitous transceivers ever made. It was sold from 1970 to1983. The circuitry is nearly identical to the Heathkit SB-102, but at a substantial savings. Some 30,000 to 40,000 were reported sold, most assembled by hams at home. I am currently restoring an HW-101 and associated power supply. You can follow my progress on the restoration and also learn a lot about the HW-101 on these pages.

**Transmitters: 6AG7/6146B System**
The AA8V 6AG7 QRP VFO Amplifier The 6AG7 Class A VFO Amplifier can be driven by an analog or digital VFO and can be run by itself as a 3 watt QRP transmitter or it can be used as a buffer to drive the 6146B Amplifier to 60 watts of output on the 80 m - 20 m bands.	The AA8V 6146B Amplifier The AA8V 6146B amplifier is a class AB2 linear amplifier that operates on the 80, 60, 40, 30, 20, 15, and 10m amateur bands. It uses a 6146B tube to produce as much 60W of output when driven by about 1W of input. Either the AA8V 6AG7 VFO Amplifier or the AA8V 6CL6 Transmitter can drive it. It functions just like a larger commercial amplifier. It has bypass circuitry that bypasses the amplifier during receive, and the use of fixed, regulated bias and screen voltages means that it is not necessary to key the amplifier.

**Transmitters: Wingfoot System**
The W8EXI Wingfoot VFO Exciter The 1955 Wingfoot VFO Exciter and modern Wingfoot 813 Amplifier form a complete, late 1950s/early 1960s high power, all tube, VFO transmitting system. The Wingfoot VFO Exciter can run barefoot at 27 watts output or drive the Wingfoot 813 Amplifierto 250 watts output on the 80 m - 20 m bands.	The AA8V Wingfoot 813 Amplifier The 1955 Wingfoot VFO Exciter and modern Wingfoot 813 Amplifier form a complete, late 1950s/early 1960s high power, all tube, VFO transmitting system. The Wingfoot VFO Exciter can run barefoot at 27 watts output or drive the Wingfoot 813 Amplifier to 250 watts output on the 80 m - 20 m bands.

**Miscellaneous**
The AA8V 6CL6 One-Tube Transmitter For crystal control, the 6CL6 One-Tube Transmitter is hard to beat. The transmitter can operate on 80m to 20m and makes a great QRP project. When coupled with the 6146B linear amplifier it makes a fine 60W output transmitter system.	Electronic T/R Switching and the Ameritron QSK-5 When I added a new Ameritron AL-572 amplifier to my shack (which I love), I also also purchased the QSK-5PC circuit board for break-in CW. I spent considerable time studying the QSK-5PC on the workbench to understand how it worked, and put everything I learned here on the web under Electronic T/R Switching and the Ameritron QSK-5. Anyone interested in how electronic T/R switching is done will find Electronic T/R Switching and the Ameritron QSK-5 quite useful.

**Academic**
Physics 340 Audio Engineering Page An information page for students at Frostburg State University taking Physics 340, Audio Engineering.	A Study of Secondary Emission and Emission Saturation in Vacuum Tubes by Angela Meyers This page is a fascinating study of secondary emission and emission saturation in vacuum tubes. It is the result of work done by Frostburg State University honor student Angela Meyers for her honors thesis. It is a beautiful example of negative resistance.

Back to Dr. Greg Latta's Educational Web Pages

Questions, Comments, and E-Mail

Letter If you have any questions or comments, you can send E-Mail to Dr. Greg Latta at glatta@frostburg.edu

Thanks for stopping by!