All posts in HAM Radio/Hardware Hacking http://www.binrev.com/forums/index.php Sat, 03 Jul 2010 20:54:18 +0000 15 http://www.binrev.com/forums/index.php/topic/43603-pandora/ Pandora Home

lostbaka]]> Sat, 03 Jul 2010 20:54:18 +0000 http://www.binrev.com/forums/index.php/topic/43603-pandora/ http://www.binrev.com/forums/index.php/topic/43563-field-day-2010/
This is when radio operators around the world go out in the middle of nowhere (or middle of nowhere surburbia) and operate a radio station (or 10) for 24 hours without mains power. If you have a ham ticket, it's a great way to get free food and talk geek with the locals... If you're new or interested in ham radio, it's a great *free* experience you can share with your kid in seeing ham radio really in action. Propagation forecasts are looking mediocre but chances are you'll hear all 50 states as well as many foreign countries dogpile on top of each other as they make contacts. If you've never worked a pileup, it's a good time to see if you have what it takes to get in or get piled on..

http://www.arrl.org/field-day has all the info including a Field Day locator to find something near you.]]> Wed, 23 Jun 2010 16:49:04 +0000 http://www.binrev.com/forums/index.php/topic/43563-field-day-2010/ http://www.binrev.com/forums/index.php/topic/43360-hamvention/
http://www.hamvention.org/]]> Sat, 01 May 2010 19:46:45 +0000 http://www.binrev.com/forums/index.php/topic/43360-hamvention/ http://www.binrev.com/forums/index.php/topic/43358-ultimate-car-project/
I want to share one project with you, I am not going to make it overnigth, but I´ve set a deadline for the end of this summer, depends on how much money i have, but I am definately going to build it.
Not a fancy car, just a ford, but some ideas what to implement.

# Premium quality sound system ( DONE! )
# DVD / TV (DVB-T) Screens
# Cameras, 1 backing ( useful for hooking up a trailer or any other precision maneuvering ) and one recording camera installed near rear view mirror, to record traffic situations.
# Navigation system. ( Stand alone, from audio ) With full EU maps, and if I get some output from GPS unit, then servo controlled license plates for speed cameras ( Illegal to use, but not to have.. )
# Thinking of radar detectors as well, but they are illegal, even when offline.
# 7-10" Touch screen car computer, with costum interface, also communicating with GPS, and Audio.
# Full connectivity over cable/BT with iPod, phone etc..
# Full internet connectivity, "KÕU" 450MHz CDMA, 3.5G/EDGE/GPRS, Wifi. Also option, to use whatever internet I have and set up an AP to share it
# Radio systems. CB radio, dual band amateur radio and a wide band scanner.
# Small things, like 220 volts etc.

At the moment I have CB and Amateur radios, GPS unit I have to probably replace, 220V, audio systems
And laptop on back seat + 3g modem for internet

Also, for antennas, it will be a forest on the roof..
CB antenna, Dual band antenna, something for scanner ( probably wire antenna under windshield ) 2x DVB-T antennas, GPS antenna, 2x Wifi antennas, 450MHz Antenna, GSM Antenna..

If you have any thoughs, or ideas, what I missed on that list, shoot!]]> Sat, 01 May 2010 09:26:38 +0000 http://www.binrev.com/forums/index.php/topic/43358-ultimate-car-project/ http://www.binrev.com/forums/index.php/topic/43253-needing-input-and-ideas-on-my-project/
Here are the ways I have thought of so far, please feel free to share any thoughts on anything I have come up with.
1. Getting a gumstix overo fire setup and installing say an Alfa driver or something similar to be able to make the wifi on the stick is able to sniff. Doing this seem the best for me as it would be the lightest weight in the air. Then to connect back I would either use something like an XBee module to send the signal back to the laptop or setup the stick with a specific IP and connect from my laptop that way. I see issues with both ways
2. Using an XBee module to power and connect ALFA adapter to, and sending the signal back through the XBee modules. Making it a wireless connection to the ALFA adapter and the UAV carries it around where I want it.

On board the UAV there is a GPS unit as well that I should be able to send signals from that to whatever way I end up going with and using that for the ability to log coordinates. Thanks for reading my long ramble and look forward to any ideas thoughts or anything]]> Tue, 06 Apr 2010 22:56:58 +0000 http://www.binrev.com/forums/index.php/topic/43253-needing-input-and-ideas-on-my-project/ http://www.binrev.com/forums/index.php/topic/43213-long-range-wireless-link/ Sun, 28 Mar 2010 22:56:59 +0000 http://www.binrev.com/forums/index.php/topic/43213-long-range-wireless-link/ http://www.binrev.com/forums/index.php/topic/43193-password-generator/ http://hobones.dogsoft.net/ov.jpg
it automatically generates, stores, and types passwords and looks like a usb-keyboard to your computer.

That's a at89c5131 dev-board, this mcu is pretty much an 8051 with usb hardware. I'm probably going to keep touching up the code a little before I start printing boards.]]> Mon, 22 Mar 2010 23:53:55 +0000 http://www.binrev.com/forums/index.php/topic/43193-password-generator/ http://www.binrev.com/forums/index.php/topic/43185-polygon-laser-scanner/
http://www.allelectronics.com/make-a-store/item/SMT-357/STEPPER-MOTOR-W/-ROTATING-MIRRORS/1.html

On the back of the unit, it says:
POLYGON LASER SCANNER
PD70LA
EX-814-02 99VA-66
COPAL ELECTRONICS JAPAN

it has 16 wires coming out of it. It is pressed together so I can't open it up and see where the wires go to.

Google has found a couple of hits on it. One site says it has a stepper motor, another says it's a 24 volt DC motor..
Apparently it was used in medical scanners and high precision laser scanners.

My google fu is exhausted. The copal electronics site doesn't have anything on this that I could find. I've emailed them, but haven't received a response.

So.. I ask you guys, do you know where to get a datasheet on this that has the pinouts and not just how flat the mirrors are? I suspect it has some kind of rotary encoders in it, and am hesitant in just sending juice into it and seeing what happens/burns.

Any tips on how I should reverse engineer this? All I have is a digital multimeter.]]> Sun, 21 Mar 2010 16:36:18 +0000 http://www.binrev.com/forums/index.php/topic/43185-polygon-laser-scanner/ http://www.binrev.com/forums/index.php/topic/43184-one-keyboard-for-3-computers/ Is there something I can buy or make that would allow me to use one keyboard for multiple computers, possibly being able to switch between each computer? Sun, 21 Mar 2010 06:19:20 +0000 http://www.binrev.com/forums/index.php/topic/43184-one-keyboard-for-3-computers/ http://www.binrev.com/forums/index.php/topic/43183-usb-hid-keyboard/
0: modifiers
1: reserved
2: key-code
3: key-code
4: key-code
5: key-code
6: key-code
7: key-code


So that accounts for key-down events. I've been poking around and I see no reference to specific key-up events. Everyone I ask is just like, oh- for key-up just send all zeros. This works but it crashes openbsd's wscons code after a few minutes so it's totally not acceptable. Does anyone know how hid does key-up events?


No, I think I got it. Reports always include what keys are down, if you want an up-key send a report not including that specific key. This still crashes openbsd however, not sure why]]> Sun, 21 Mar 2010 03:34:48 +0000 http://www.binrev.com/forums/index.php/topic/43183-usb-hid-keyboard/ http://www.binrev.com/forums/index.php/topic/43152-microwave-receiver/ can anyone post a good tutorial on how to make a 2.4ghz microwave reviever, and how to use it? Fri, 12 Mar 2010 15:44:37 +0000 http://www.binrev.com/forums/index.php/topic/43152-microwave-receiver/ http://www.binrev.com/forums/index.php/topic/43141-gps-jamming/
I read some documentation I could find on GPS devices and the Pcode and C/A data are carried on 2 frequencies called the L1 and L2 bands at 1575.42 MHz and 1227.60 MHz. Would I need to broadcast something else on these frequencies to confuse the device? and if so would this be done with a crystal oscillator?

Is this even possible?]]> Wed, 10 Mar 2010 00:09:42 +0000 http://www.binrev.com/forums/index.php/topic/43141-gps-jamming/ http://www.binrev.com/forums/index.php/topic/43097-hacking-an-itrip/
i'd like to modify this belkin itrip type thing to transmit on frequencies other than the ones it allows for (88.1, 88.3, 88.5, 88.7) i'd like to transmit on frequencies between 92 and 100.

i opened the thing up and it has this chip doing the rf transmission, it's this: bh1417f

from the datasheet it looks like i can transmit on different frequencies (87.7-88.9 & 106.7-107.9) by manually setting pins on the chip but it doesn't say anything about transmitting between those 2 ranges, BUT digikey tells me that frequency is 76MHz ~ 90MHz, 87.5MHz ~ 108MHz

now am i completely restricted by the chip? or are there certain things i could do to modify the output like changing the crystal slightly or something like that? am i headed in the right direction or would it be way easier to learn how a fm transmitter works and build one from scratch?

thanks!]]> Wed, 03 Mar 2010 15:25:28 +0000 http://www.binrev.com/forums/index.php/topic/43097-hacking-an-itrip/ http://www.binrev.com/forums/index.php/topic/43083-cromemco-z-2-zpu-card-up-and-running/
I decided to skip the power supply rebuild, and use the Wunderbuss board with a bench supply, since it's small enough to keep on my desk and work on. It had a cut track in the data bus, and had part of its active termination circuitry removed -- presumably it failed first when the machine's diodes shorted and put AC on the bus. The last of the parts for the terminator came in last week, so I finished repairing it.

The next step was getting the ZPU card working. I've played around with Z-80's before, as well as the 8085 (they both run binary-compatible 8080 code). I found out the clock wasn't making it to the system bus, and that the signal on the Z-80's clock line was really ugly. Turns out that the two 7474 D-type flip-flops used in the speed selector (you can run a ZPU board at 2 or 4 MHz) was dead, and a section of the 7404 inverter in the crystal oscillator circuit was dead. After replacing these, and replacing the 74367 bus drivers someone had scavenged from the board, it appeared to be running.

The next step was in building a "HALT card" -- a S-100 board capable of delivering a HALT instruction to the Z-80's data bus. The S-100 standard provides a line that indicates the processor is halted, so I attached an LED to it through a 2N2222A transistor. Usually, you test for halt with an EPROM containing nothing but HALT instructions -- 0x76 at every location. Since I didn't have an EPROM board, I decided to hard-wire a DIP switch with pullup resistors to the data bus. That way, you could set 0x76 by hand and it'd appear at every location in memory. On reset, the HALT light lit:



Next, I added buffers for the Data In and Address buses -- just a bunch of 74ACT245 buffers. These feed address data into a 2716 EPROM and DL-2416 ASCII character display. There's some decode logic that selects the 2716 on memory read requests from the data bus, and selects the display on I/O writes. Since the memory map is the same as the one I used in my 8085 project, I was able to use the same test code to write characters to the display. The PDSP-1881 used in the 8085 board is addressed in reverse from the DL-2416, so "HELO" appears as "OLEH" -- still shows that the ZPU is reading and writing to memory and I/O just fine! There's a HALT at the end of the test program, so the HALT light is lit as well.



I'm working on adding serial I/O to the board with an Intel 8251 programmable serial controller. That will let me exercise the RAM on the 64K RAM board, once I get that working (I haven't tested it yet). I've got a Cromemco 4FDC controller card as well, which provides a serial terminal, floppy controller, and ROM monitor. If I can get it all working, the Z-2 and an old Heathkit H19 terminal will probably come with me to the Next HOPE, so that people can play around with it!]]> Sun, 28 Feb 2010 21:02:31 +0000 http://www.binrev.com/forums/index.php/topic/43083-cromemco-z-2-zpu-card-up-and-running/ http://www.binrev.com/forums/index.php/topic/42961-building-an-8085-based-computer/
Recently, though, I've found a few situations in which I'd like to have a microcontroller system with a true address and data bus, rather than implementing them through the larger PICs' output ports. I decided it was finally time to put together a basic 8085 system, since I'd now accumulated many 8085 CPUs, plenty of static RAM, and had acquired my own EPROM burner. This is the result:


I built my prototype for the project on a Vero project board, which contains traces oriented for DIP ICs, as well as power and ground planes. I started off with just the 8085, a 74LS373 8-bit latch for the multiplexed address bus, a 2716 2k x 8 EPROM, a 2 MHz crystal and some decoupling capacitors. I later added the small, red TIL311 hex display, and a 74LS04 hex inverter to supply its internal latch with a signal of correct polarity. The EPROM was wired directly to the data and address buses, with its Chip Enable tied to the Read output of the CPU, since there were no other memory devices present. The TIL311 was wired directly to the low 4 bits of the data bus, with its noninverting Latch Enable fed from the CPU's inverted Write line, through one of the inverters in the 74LS04. I wrote a short assembly program to output 0x0A on output port #0 (any port would work, as the TIL311 responded to any write from the CPU). The program was assembled using GNUSim8085 (an open-source 8085 assembler and simulator), tested, then the hex dump was manually entered into my Intel iUP-201 PROM programmer, which has a keyboard for the manual entry of hex data into a PROM. After fixing two swapped address lines, the program worked fine, and displayed "A" on the TIL311.

The next step was to add some RAM, for use as the 8085's stack, and for general storage of variables. I chose two uPD-2114 RAMs, which are 1k x 4 static RAMs -- you parallel two for 1k x 8. Since there was going to be real RAM and ROM present, it was necessary to come up with select logic to choose the EPROM or the RAM when memory accesses were performed, or the TIL311 when IO accesses happened. The 8085 provides IO/M, RD, and WR status lines, with M, RD, and WR being inverted (IO/M is one line, with 1 = IO access, and 0 = Memory access). The select logic was composed of inverters and NAND gates, from the 74LS04 and 74LS08 ICs. During this modification, I decided to add a PDSP-1881 8-character LED display for ASCII output. This was added to be activated on output ports 0-7 (one port for each character). Finally, I wrote an assembly to push "HELO" onto the system stack, then pop each character off and display it on an incremented output port. After correcting a timing error (the PSDP-1881 wasn't syncing with the 8085's clock), "HELO" appeared on the display after reset:


Here's a shot of the point-to-point wiring on the back of the board. It's 30-gauge Kynar wrapping wire:



I'll probably keep this board as-is for future embedded projects, but I plan on building a more complete system using an Augat wire-wrap board, since the point-to-point hand wiring is somewhat tedious. I've got an electric wire wrap gun for this purpose, and several different lengths of precut wrapping wire for this purpose. I'll probably add either an HD44780-based LCD or a serial UART next, with the intent of writing a small monitor program for the system. Eventually, I'd like to be able to load CP/M from ROM or perhaps floppy disk on the system.

If anyone is interested, I can post scans of my schematics, notes, and assembly code for this project. I've also got a pile of extra components, if anyone would like to build an 8085 system similar to this one. If one were to use the same memory map, code should be interchangeable between systems. If you'd like to build something like this, but lack a PROM burner, I could post my schematic for a manual programmer I built several years ago: you manually set the address and data bits, then trigger a 555 timer to provide the programming voltage pulse to the EPROM without damaging it.]]> Sat, 30 Jan 2010 18:34:44 +0000 http://www.binrev.com/forums/index.php/topic/42961-building-an-8085-based-computer/