2018 Central States VHF Conference

Medium Power Amplifiers using Larcan Surplus TV Amplifiers

2m and 6m 600 Watt amplifiers using Larcan and W6PQL modules

Presented at the 2018 Central States VHF Society Conference by Dave Pedersen PJ4VHF / N7BHC

n7bhc@drasticom.net

This presentation and paper describe the construction of a medium power amplifier in the 500-600W range based on modified Larcan VHF television amplifier modules and W6PQL control modules. This medium power amplifier uses the 500W Larcan IPA2 visual driver stage.

The closure of analog high power TV stations in North America led to a surplus of amplifier modules. The Larcan amplifiers are commonly used on 50, 144MHz, and 220MHz. They are available in 500, 1000, and 1500 Watt versions. The 1kW and 1.5kW modules already have mods published. These earlier articles provided the basis for the 500 watt amplifier discussed in this article. As these amplifier modules are designed for television service, they can run full power at 100% duty cycle for months on end as long as they are well cooled, making them well suited for digital modes.

The amplifier module itself is just part of the complete amplifier unit. Additional sections required are the case, power supply RF cabling, and control. The control modules sold by Jim Klitzing greatly simplify the construction of high power amplifiers. The W6PQL modules are a vital part of this amplifier project. The techniques described here are applicable for modified Larcan amplifies up to the 1500 Watt version, as well as the W6PQL amplifier pallets ranging from HF 1.5kW to 1296 MHz 600 Watt units.

A video of the presentation can be seen on the CSVHF Society Web page.

The "Files" section of this website contains two documents from the Conference

1. The Article as published in the Proceedings of the conference

2. The PowerPoint presentation from the conference.