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JAQ's Blog - Electronics, Microcontrollers, DEC Minicomputers, Raspberry Pi, Airplanes and other stuff....
Total: 24 results found.
Page 1 of 2
IOT for the Small Block - Part 1
... This is the first in a series of posts describing how I have used an IOT device (a li
e computer really) that connects to my block wide WIFI network and does really useful things. The basis ...
GPS Connection to Hans Summers Ultimate 3 QRSS Kit
... approach is as follows: Wait 5 seconds on startup for things to se
e Start receiving serial data from the GPS at 4800 baud looking for 0x0D, 0x0A,$ indicating the GPS is in the default ...
TRS80 Model 4 Fault
... the power on pins 11 (VCC) and 29 (VSS) of the Z80 (U57). This read 4.7 volts... a li
e lower than I expected but was consistent if I powered the main board from either power supply so I assumed ...
SBC6120 PDP8 Replica - Part 1
... and spent a lot of time using the department machines while I was waiting for my ride home. Even in the 1990's the PDP8e was still operational and lived in a li
e "computer room". From ...
Switching Mains Equipment with a Raspberry Pi - Part 1
... 74HCT244 are tried to ground to prevent oscillation. The 74HCT244 is run at 5V. The 74HCT is a CMOS device that uses
logic levels on it's inputs. This means that >2V on one of ...
Supporting Generic Kermit 4.11 in your CPM/80 BIOS
... on prototype board as long as you take your time and keep your interconnect wires short. The hardware uses a Z80-SIO to provide two serial ports (with
to USB adaptors on my build). ...
Using eBay TTL Serial/USB Interface Modules
With most computers no longer having a serial port, a
Serial / USB interface is required for many microcontroller projects. I have had good results with the low cost eBay modules based on ...
Home Built Z80 CP/M Computer - Part 3
... The end result looks very smart. The two serial interfaces use CP2102 USB/
Serial interface adaptors purchased on eBay for a couple of dollars. They work well in this application easily ...
Home Built Z80 CP/M Computer - Part 2
... Compact Flash to IDE Adaptor on eBay (approx US$ 2). I have been testing the board with 2 x MAX3232 based
to RS232 converter boards. Replacing these with CP2102 based
to USB Serial ...
Home Built Z80 CP/M Computer
... circa 1979 but combine this with 128K of Static RAM, 128K of Flash and a 128M compact flash drive, over clock it to over 7 mhz and you have a li
e CPM machine on a single board with capabilities that ...
PDP-11/04 - Power Supply Part 7
... output is a li
e high at 5.5v but I understand that these do not have great regulation when not under load so this will likely come down with 10 PC boards to power. The other +5V supply didn't ...
eBay AD9850 Module Test Board
... a great starting point for a signal generator project but are a li
e short on documentation. The pinout and relationship to AD9850 pins is as follows: Board ...
eBay AD9850 Module Pinout
The cheap AD9850 DDS modules currently available on eBay are a great starting point for a signal generator project but are a li
e short on documentation. The pinout and relationship to ...
Who is using the water?... the bore monitor speaks
... Sender and Receiver are available here. The Receiver uses a
output to indicate the bore running state. By querying every 5 minutes and storing the data in a MYSQL database on my server ...
Mangaging your FT-7800R memories.... with a VX5 bonus
... parts... the level conversion was easy... standard MAX232 design but additional interfacing was required to covert the two line
serial to one line to suit the FT-7800R. I discovered this design ...
Building a DLink DSL-502T Based IGate
... doesn't say is that there is an onboard serial port (even provided with soldered pin headers) which is perfect (with level conversion from RS-232 to 3.3V
) for connect to an TNC. Using a DSL-502T ...
Thoughts on the Puxing PX888
... choice of 3 colors. The programming software (while typical of software written by hardware engineers so the UI leaves a li
e to be desired) is easy to use and is the quickest way to get the radio ...
RF Datalink using a PICAXE UART
... symbol POWER = 4 ' Constants - Other symbol SENDDELAY_H = $300 symbol SENDDELAY_L = $5 symbol FASTTXLIMIT = 48 symbol POWERSE
E = 150 ' Variable Usage ...
APRS in an Ammunition Can
... a self contained APRS unit. There was plenty of enthusiasm for the project.... so much so that we ran out of PCB's.... so I built my OpenTracker using a DSE Prototyping board... a li
e more time ...
Take a Message....
... anniversary of the Ba
e of Britain in 1940. Among the aircraft that flew that day was Miles Messenger IIA ZK-CMM. The Messenger was owned by the late Dave Cowie and is flown ...
PDP8 SBC6120 FP6120
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