[MRCA] Fast RTTY

[Ray Fantini]

Plowing forward on my 1980 digital RTTY project, going to be building the input UART that will convert the digital level output of the Dovetron TU this weekend. That will provide me with a five bit word that the ROM board will convert to a seven bit ASCII word that the MX Tactical terminal will understand.
The MX family of terminals run at 75, 600 and 2400 baud. I have the UART that converts the seven bit word to a serial word the MX understands and sends it to the MX at a blinding high speed rate of 75 baud. The real problem will be going from the MX to the Dovetron at 60 WPM, going from 60 WPM (45.5 baud) up to 100 WPM (75 baud) is no issue. The problem occurs with the way the MX Terminal works. You cannot transmit in real time. You have to write to a buffer in the terminal and then go to the SEND function on the terminal and dump the entire message at once. When going from 75 baud to 45.5 baud you would have to store data in the message to make up for the added time required to clear the data thru the UART.
Long story short, wont have any issues reading 60 WPM traffic on the terminal but looks like I can only transmit if both stations are running at 100 WPM
What's the feeling about getting some of the 28 people out there to get those old teleprinters to chug along at that speed?

Ray F/KA3EKH

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