Design

555 monostable circuit design
I have a GPS unit which I'm mounting in the trunk of my car powered by the 12v lighter plug in the trunk. The socket has power only when the key is on and the GPS unit requires its power button to be held down for 1 second to activate it. If I were to use the 555 monostable circuit I found (link below) to trigger a... 7 Apr 2006 10:37

Running Palasm on WinXP
Has anyone been able to get Palasm 4.5 to run on Win XP? I've heard it can be done, but so far it has proven to be beyond my abilities to get it going. Any advice would be appreciated. ... 6 Apr 2006 13:50

PAL's and GAL's
Hi ppl, I need to program sevetal PAL's and GAL's in an educational enviroment. I will be using a hobbyist programmer to do the programming as i do not need any large volumes. What software is available to enter the logic equations and compile to the fuse file? Does any schematic entry software exist which one... 1 Apr 2006 19:54

LEAD ACID BATTERY
Hi, I have to design a voltage source ( +/- 18volts, 13A ) using lead acid batteries. My circuit draw is 700mA and requires plus minus 18 volts to operate efficiently. I need batteries that can atleast run for 10 to 12 hours before the voltage drops to +/- 17 volts. I am thinking of adding three 6 volts, 13AH ( ... 6 Apr 2006 15:56

Oscillator
In some prior posts there have been inquiries regarding low distortion oscillators. Out of curiosity I simulated a 200Hz oscillator made simply from an A1A-style gyrator BP filter, then wrapped a positive feedback loop around it, with back-to-back diodes used to limit the drive to the input to the BP filter. ... 7 Apr 2006 13:13

PLL as modulator og demodulator
I would like to use one PLL for both FSK modulator and demodulator because of price. I probably gonna switch between a tvxco and FSK input to "sig in" on a 4046. I gonna modulate the FSK on after the Loop filter. My consern is about the loop filter. When I am using txvco as center carier frequency I would like a sm... 6 Apr 2006 08:05

Astec LPT42 PS schematic
I am trying to find a schematic on a Astec LPT42 3 output switch mode open frame power supply. It seems Astec does not supply schematics. The -12 volt regulator (IC3), blew apart, filter caps domed, and it seems the 1/2 wave rectifier diode is shorted (D15). I am assuming IC3 is a 7912 or such, but would like a kno... 25 Mar 2006 00:26

National switching regulator LM2678
I'm using the LM2678-ADJ and have the output set to 4.4V. This is a somewhat arbitrary value during my course of testing a circuit including this regulator. I'm connecting a litte more than a 2ohm resistive load across the output, so it should draw less than 2.5 amps; well within the regulators 5 amp rating. I'm... 25 Mar 2006 01:27

counter circuit help needed
Electronics is not my field, so I scoured the internet to find counter circuits, but none of what I found really hits my exact needs. I'm looking for a 2 or 3 digit counter that will count down from a predefined number to zero - with a RESET switch to send the count back to the max number. From what little... 8 Mar 2006 10:51

POWER SUPPLY
I'm designing a power supply which uses a transformer, Full wave bridge rectifier, capacitor and an inductor. Is there any reason why I should use an inductor and a capacitor rather than just a capacitor. Jimmy ... 28 Feb 2006 19:13