Archive for the 'electronics' category
The BeagleBone is a low-power open source hardware single-board computer designed with open source software development in mind, and as a way of demonstrating the Texas Instrument’s OMAP3530 system-on-a-chip.
Finally I’ve finished my old PSU’s renewal. I added overvoltage protection and a slim fan which is switched on by bimetal thermostats on the heatsinks when the temperature reaches 45°C. I bought both the slim fan and the thermostats on eBay. The overvoltage protection is a very simple circuit: when the voltage is above a […]
Here’s how to repair a Denon S3000 CD player which gives “Disc read error”: You don’t need to dissassemble the whole unit, only unmount the CD drive: You’ll need to replace the laser pickup. According to the service manual, this player uses the Hitachi HOP-1200R (HOP-1200S and HOP-1200W are also compatible with this unit). I […]
1 or 2 months ago my EMU 1820 soundcard has started to play noise instead of music when I switched the output sampling rate above 44.1kHz. Plus the volume randomly changed for 10-20 minutes after I booted up my computer. I disassembled the external box and found 2 faulty capacitors. After replacing them (and reinstalling […]
Writing the APRS freq to the EPROM of my VHF Grundig FK105: Tinkering with a Compaq Portable III and other DOS stuff:
I made a Kenwood CAT cable for my TS 850 with the help of my buddy HA1TN. The TIL113 optocoupler was not fast enough for 4800 baud, so we used a HCNW3120 (a little overkill, but it works fine). :)
I ‘ve just finished the fliphack on my HV30, now I don’t need mirrors to flip the viewfinder’s image. It was not very difficult to do, but took a lot of time. I followed this guide.
This is my latest purchase on ebay, a very nice portable microphone preamp/mixer. I’ve just brought it home an hour ago. I’ll use it mainly for my camera, but I’m also planning to record acoustic guitar and other instruments with it.
Wouxun KG-689 wiring schematics: Data cable wiring: