EEVblog #1130 - Mailbag Monday - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: October 08, 2018, 11:34:19 pm
content: More Mailbag MondaySPOILERS:A-TEK AT-601 PC ISA Bus Design Breadboarding ToolGigatron TTL computer updatehttps://gigatron.io/VintageTek museum XY demo boardhttps://www.ebay.com/str/vintagetek1970's Casio CQ-1 CalculatorZofz PCB Gerber Viewerhttps://www.zofzpcb.com/

author: maginnovision
author_rank: Super Contributor
timestamp: October 09, 2018, 12:01:31 am
content: I was just messing with one of those tek boards and some other oscilloscope art stuff last night.

author: Muttley Snickers
author_rank: Unknown
timestamp: October 09, 2018, 12:02:50 am
content: 8:30Use  to selectPress  to start program"Do I have to read the instructions"

author: EEVblog
author_rank: Unknown
timestamp: October 09, 2018, 12:47:43 am
content: Quote from: Muttley Snickers on October 09, 2018, 12:02:50 amThey are the same instructions as for the original ROM that used the Nintendo controller thing, so I kinda just subconsciously ignored them assuming that the keyboard version worked more sensibly.

author: marcelk
author_rank: Newbie
timestamp: October 09, 2018, 01:06:58 am
content: The programmer* also didn't see that line for months.https://github.com/kervinck/gigatron-rom/issues/38*me

author: drussell
author_rank: Super Contributor
timestamp: October 09, 2018, 02:36:32 am
content: GreatMailbagepisode...i would expect that the 244 on the ISA card was probably fried and replaced by a user rather than being mismatched from the factory. I've certainly blown up my share of 244 and 245 chips.Does the CQ-1 power up at all? It shouldn't be terribly difficult to diagnose basically what is wrong.

author: mrpackethead
author_rank: Super Contributor
timestamp: October 09, 2018, 03:26:33 am
content: Hey Dave, just noticed this particually on this videoThe audio in your video is below the Youtube Reference level by 4.9db Youtube does weird things with normalisaton and stuff, ( you can google this topic ).You might want to run a loudness meter in your audio, before you push it up to Youtube, to get it up to about -22 LUFS

author: ggchab
author_rank: Frequent Contributor
timestamp: October 09, 2018, 07:13:09 am
content: Nice videoAnother demo of the Tektronix logo board by w2aew:

author: Brumby
author_rank: Unknown
timestamp: October 09, 2018, 01:54:40 pm
content: Tandy were selling their Radio Shack branded version of that Casio alarm/calculator back in the day. I remember working in their store in Westfield Parramatta when they came in. They were the ants pants.

author: Lajon
author_rank: Contributor
timestamp: October 09, 2018, 03:51:26 pm
content: Still have my Casio CQ-1 (from 1977 in my case), it stopped working some years ago (the display and one or more switches I think). It's actually not strictly a "4 banger", it can compute with date and time (like number of days between dates). Ok, not super useful but everyone got to know their age in days./Lars

author: Ferenc
author_rank: Newbie
timestamp: October 09, 2018, 05:01:17 pm
content: That's a knife!

author: SeoulBigChris
author_rank: Regular Contributor
timestamp: October 09, 2018, 10:29:29 pm
content: I built a circuit back in the day to display the polarization of an RF signal in real-time on an oscilloscope, similar to this Tek device but not quite so fancy. I only drew a polarization ellipse on-screen, and used the z-axis to make the trace look like a dashed line for counter-clockwise polarization (solid was clockwise). I’m surprised the Tek device doesn’t use the z-axis to “pick up the pen”, so to speak, while tracing out the sketch. Without z-axis modulation, it’s like drawing something on an etch-a-sketch.

author: bitwelder
author_rank: Super Contributor
timestamp: October 11, 2018, 11:02:49 am
content: It seems Dave missed one special feature of the Vintagetek XY demo board: play tennis on the CRO!Quote