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*** Yes, indeed. I had forgotten, it was a long time ago. Around 1970. I had a railroad surplus model 15. Which had no case. To say it was loud would be an understatement. - Jerry

The failure mode on your RTTY terminal is similar to that of applying a signal in the threshold region to a logic gate: Typically an issue only on really high power parts, careful design can usually

One small nit... BAUDOT does not have upper and lower case. Uperr only. The shift weas for non-alpha characters. bill

All, Here's a real world example of damaging undervoltage: I once built a RTTY TU ( Terminal Unit ). The teletype had a "loop" consisting of a 120VDC power supply feeding a resistor and going to the

CMOS input pins typically have on chip Schottky protection diodes to both the Vdd rail and to ground, so any input signal above Vdd or below ground gets clipped by those diodes. If the driver into

Indeed. That's the power supply sequencing issue I mentioned in an earlier post.

If the voltage to the display is lower than the voltage to the micro, the voltage on the input pins on the display could be higher than the supply voltage to the display, then there is a problem that

Great to hear! Thanks, Dennis! Reed

I'm still catching up on this thread. Robert AG6LK wrote: "I'm not sure why there could be damage to a display if the voltage dropped. On the enclosed paperwork, that came with the Nextion 5”

It may be possible to design a logic gate that works fine at 5v, and self destructs at 4v. Such a product would not sell very many units.

A low power supply voltage can cause electronics to do unexpected things. but pretty much never causes damage.? ?When bringing up a new board,? you are far more likely to cause damage by bringing

It's already up to $52 plus shipping. I have an untouched, unbuilt v3 still in the shipping box. Never opened, never touched by a soldering iron. What would be a fair price? Any interest here? Clay

Anyone wanting the TSW Teensy 4.1 Raduino kit, they are still available.? We have located a source of 5351 clock/VFO chips and it turns out that Mouser electronics, at least, has over 700 Teensy

Reed, I want to thank you for the excellent job you did on the manual. It was easy to read and the steps for updating the firmware were easy to follow. I ran into no hitches even though I had no

Great write up Reed, This deep work and you explained it so well. Like me, I am sure many of us here have picked up so much from it all. I was always curious of how the totem pole worked with varying

Over at /g/BITX20/topic/ubitx_v6_specifications/82557868 I saw some folks wondering how in the world something could be damaged by undervoltage, since as we all know, when things are

Hi all, Thank you for all for your information and comments. Bill, I'm not sure why there could be damage to a display if the voltage dropped. On the enclosed paperwork, that came with the Nextion

Bought a very nice chassis and ordered a ver 6 board. Looking to buy a 5" Nextion display....what is the best model number? I see a few choices on amazon. Thank you - Mike

At this price... Go for it, it’s not even the price of spare parts. There may be only one transistor to change?? Too bad no shipping to France.

Thanks, I will be doing that. Earl Cox? KB5UEW?Reply or E-mail me at:? kb5uew@...