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I'm really liking some of the color combos people are coming up with.
Left : 2 - 19 - 5
Right : 4 - 23 - 8
The ATtiny13 is accepting a program, but I've not yet written the program for it! All connections seem fine.
NOS Parts from an estate sale.
Previous owner had been in HAM radio for the better part of 60 years and accumulated quite a collection of parts from the late 1950's to early 1960's.
Most are New Old Stock, with some parts being used but working.
APRS repeater based on Raspberry PI as demonstrated by its owner, Howard G1BYY at a technology day held in February at St Albans Community Fire Station
This is part of the workings of my beloved old MouseMan Wheel from around 1997. I finally gave it up a couple of years ago when it stayed disgustingly-grimy even after cleaning. It was time to go optical anyway.
I bought a LAP-C-16032 some years ago and upgraded the hardware in the unit to have 32 channels. The h/w upgrade cost in the order of £5 total.
The memory device was capable of 128k samples per channel but was crippled by software to 32k only. There is software around that allows this to be edited but it never worked for me (wouldn't compile).
Being a h/w engineer I took a different approach. I constructed an interface using a small Arduino Nano circuit board (£1 off eBay) on a piece of scrap Veroboard and tacked some wires onto the onboard EEPROM (93LC46).
The Arduino is a 5V part and the EEPROM was running at 3.3V requiring a level shifter. This comprised of 4x resistive divider networks, 3x for the EEPROM and 1x for the GL660 USB interface device that talks to the EEPROM. The additional control to the GL660 was to allow it to be held in a reset state to allow the Arduino to talk without interference.
A simple Arduino script allows the EEPROM to be read and written. Decoding what to change is documented on the web.
The above has successfully allowed me to use the full 32 x 128k capability of the device, all for a very nominal cost. The change to the EEPROM allows the newest drivers and software to be run without modification.
My setup for Arduino development. Includes an extra max232+Serial2USB adaptor for debugging (no need to quit screen when uploading programs), a serial VFD so I don't have to use screen :p, a Parallax 4x4 Keypad with 74C922 keys encoder, a 595 shift register for outputs and a piexo buzzer for feedback. The RS232 to USB adaptor also has the advantage to work driverlessly on Mac (at least in 10.4.8 and above).
The RX converter portion of my LF 10MHz transverter. The board above the breadboard is an early attempt at a Lowfer beacon that I'm using to test the RX converter. The spool of wire is being used as an "antenna" to receive the unamplified signal generated by the TX.
Changes applied for this PCB version:
1. Directional Wires now match the Wiring Harness Colors of the Sanwa JLF series, making connections easier to follow without the need for labels.
2. Start, Back and Gude now have different colors.
3. A, B, X, Y, LB and RB all have either accurate color wiring or a unique color.
Audio, Bread Board, Electronics, Electronics Circuits, LM358, Laboratory, Made, Near Future Laboratory, Observations, Op-Amp, Oscilloscope
Here's the circuit for the Black Box Lightshow. I'm pretty sure it's right. And now, an explanation:
The LED array is shown here as individual diodes, though I used six 5x7 LED arrays, each one is 2" tall. They are arranged as 14 rows and 15 columns. The left channel is 8 columns and the right channel is 7 columns. The extra column from the left channel is the center column and gives nice symmetry. Not shown here is that on the right channel, the first column (pin 1) is not used so that the other columns are equal.
The LM3914 is a Dot/Bar Display Driver. It does all the heavy lifting of converting the audio signal into a series of bars - these are typically used as digital meters. The potentiometer sets the sensitivity of the display. Since the rows are multiplexed (see below), each column is only driving one LED at a time. I only show the left channel here, the right channel is identical, and they share the level setting potentiometer.
The right portion of the diagram is a 555 clock, a 7493 4-bit counter and a 74154 4-to-16 line decoder/demultiplexer. This is the "sweep" part of the display that cycles through each row of LEDs. The potentiometer at the top controls the sweep speed. The net result is that the 74154 is cycling through the pins/rows, grounding each in succession. Note that I only have 14 rows, but it is counting to 16 each time. No big deal, it doesn't affect the perceived output at all.
The N2907 transistors are there to provide enough power for all the LEDs. Potentially, all 15 LEDs in a row can be lit up at once, so the transistors make sure there is enough juice.
Unfortunately, I lost the original plans during a garage cleaning after I built the electronics (the box took another few months before I got around to it). I opened it up and reverse engineered my own work. I won't guarantee it, but it sure looks right to me. The one weird thing I found is that I don't have power going to pin 8 of the 555 (as shown here), but it works fine - go figure. Also, I'm not 100% sure I got the polarity of the LEDs right, sorry about that. I would recommend testing that out first.
Please post if you build this and let me know! Also, happy to answer questions along the way.
6W RMS total output power.FM digital tuning with presets.Neodymium speaker driver for rich and clear sound.Play and charge your iPod/iPhone simultaneously.Dock any iPod/iPhone, even in its case.Time and alarm backup for on-time wakeup even with power cut.Sleep timer for easy falling asleep to your favorite music.MP3 Link for portable music playback.Auto clock synchronization with iPod/iPhone when docked