3021N ⁽⁸⁾

The OCXO card is a somewhat standalone reference oscillator made for the 3021N receiver. This card was finished in late 2022.

Note that this part of the series is published out of order, at the time of first issue this PCA has not been integrated into the radio, but a copy of the PCA has been integrated into a 19" rack unit.

The RF Section or 1st Converter consists of the pre-amplifier, first mixer, and first IF filter in the receiver signal chain. This is typically the most important part of the radio since it determines the sensitivity and selectivity of the radio.

This card was finished in late 2022, at the time of initial publication it has not been integrated yet.

The 3021N Synthesizer is a very complex part of the original radio. It's almost sad to replace it, but I needed the room to fit new power supplies. The synth was designed in the fall of 2020.

This is part of a series covering the 3021N communications receiver. This part covers the Demodulator, and was the third part of the receiver that I replaced with a modern expansion. The demodulator card was finished in the middle of 2020 (I wasn't too busy).

This is part of a series covering the 3021N communications receiver. This part covers the DSP, and was the second part of the receiver that I replaced with a modern expansion. It replaces the Audio Amplifier PCA. This card was designed in late 2018.

This is part of a series covering the 3021N communications receiver. This part covers the Scan Tune Logic PCA, and was the first part of the receiver that I replaced with a modern equivalent, in the middle of 2018.

This is part two of a series covering my extensively modified ITT Mackay Marine 3021N communications receiver.

This article covers various details on the chassis and the signal path. More details of the various cards are given in later articles covering their replacements. The work covered in this section took place between 2017 and 2021.

The ITT Mackay Marine 3021N is a mid 70's communications receiver, designed for merchant marine and military use. I've basically built it again using modern electronics, which will be covered in detail in this series.

This is part 1, covering the basic overview of the receiver and its role in the original marine communications system. I acquired the 3021N some time the middle 2010's, and started serious work on it in 2018. The series has its own tag: 3021N