Search found 85 matches

by rstofer
Sat Jul 02, 2005 10:25 am
Forum: General Discussion
Topic: 556 timer triggering problem
Replies: 30
Views: 5904

Re: 556 timer triggering problem

I think I would remove the differentiator (R1,C2) and try DC coupling.<p>Alternately, I would increase the size of the capacitor. Maybe 1 ufd - anything to guarantee that I could pull the trigger input down to zero. I'm not sure the existing circuit will do that.
by rstofer
Fri Jul 01, 2005 1:33 pm
Forum: General Discussion
Topic: Surface Mount Chips
Replies: 10
Views: 2252

Re: Surface Mount Chips

Can I get a socket for a QFP 208? If so, where...<p>Thanks!
by rstofer
Fri Jul 01, 2005 12:12 pm
Forum: General Discussion
Topic: Surface Mount Chips
Replies: 10
Views: 2252

Re: Surface Mount Chips

See the 3d video on this page: http://www.howardelectronics.com/navigate/videoclips.html It actually works!<p>I haven't tried it with 0.5 mm spacing but it works well with 0.65. Plus the flux works well for everything else. I will never allow myself to run out!<p>The flux is NC-559-V2. Unfortunately...
by rstofer
Fri Jul 01, 2005 9:02 am
Forum: General Discussion
Topic: Decoding automotive RKE (Remote Keyless Entry) signal us
Replies: 12
Views: 2470

Re: Decoding automotive RKE (Remote Keyless Entry) signal us

The way it is done when using a PIC for decoding IR Remote Control signals is to start a timer counting at the leading edge of the first pulse and then timing and recording pulse and gap widths until some long pause occurs.<p>It should be quite possible to store this pattern in the internal RAM of t...
by rstofer
Wed Jun 29, 2005 4:55 pm
Forum: General Discussion
Topic: mystery connector?
Replies: 15
Views: 3717

Re: mystery connector?

Amphenol says BNC stands for Bayonet Neill Concelman after the Amphenol engineer that developed the device, Carl Concelman.<p>See http://www.amphenolrf.com/products/bnc.asp
by rstofer
Wed Jun 29, 2005 10:22 am
Forum: General Discussion
Topic: controll boat
Replies: 5
Views: 1458

Re: controll boat

Autopilots for smaller sailboats (those with tillers) often use a linear actuator. All designed, built and ready to go.<p>Many autopilots connect to GPSs but there are issues...
by rstofer
Tue Jun 28, 2005 2:17 pm
Forum: General Discussion
Topic: RANGE FINDER
Replies: 12
Views: 3257

Re: RANGE FINDER

True, but I doubt that anyone else can measure that acurately and it is certainly not possible with a GPS. After all, the shoreline moves with the tide.<p>I would just try to get a reading < 2 degrees and call it good. Besides, I wouldn't want to get that close to the beach.<p>It's not the water but...
by rstofer
Mon Jun 27, 2005 10:21 pm
Forum: General Discussion
Topic: RANGE FINDER
Replies: 12
Views: 3257

Re: RANGE FINDER

Trig...<p>Take a board and mount a plastic protractor and a plumb bob (use a thin wire rather than a fat string) so that you can sight from your vessel to the shoreline. When you have the sight, clamp the plumb bob and read the angle.<p>Assuming a 10' height of eye, a reading of 2 degrees off vertic...
by rstofer
Mon Jun 27, 2005 9:00 pm
Forum: General Discussion
Topic: Pic circuit with built in programmer
Replies: 6
Views: 1341

Re: Pic circuit with built in programmer

As far as the 16F877 bootloader from Junun, the only accomodations required are: you can not set the fuses, your program must be ORGd at 0x003 (you can't use addresses 0x000..0x002) and the upper 2k is reserved.<p>There are other bootloaders around. Microchip has some as well. I have used the 16F88 ...
by rstofer
Mon Jun 27, 2005 7:42 pm
Forum: General Discussion
Topic: Pic circuit with built in programmer
Replies: 6
Views: 1341

Re: Pic circuit with built in programmer

Maybe all you wish can be done but I doubt it. If it was possible, somebody would have posted it to the Internet.<p>If you really want serial port programmability, why not consider a boot loader? These can be fairly small in code space and use the USART for transfer.<p>The next problem is the progra...
by rstofer
Sun Jun 26, 2005 7:12 pm
Forum: General Discussion
Topic: Three phase power, from 220V line??
Replies: 7
Views: 2887

Re: Three phase power, from 220V line??

No, and very probably the phase common to two poles will eventually be overloaded.<p>At the end of the day, the National Electric Code requires apparatus to be installed as intended, either by the manufacturer's instructions or the UL listing. This panel, as installed, does neither.<p>[ June 26, 200...
by rstofer
Sun Jun 26, 2005 2:10 pm
Forum: General Discussion
Topic: zilog z8 encore! xp
Replies: 18
Views: 3928

Re: zilog z8 encore! xp

Do they provide a schematic that can assist in determining the proper settings?
by rstofer
Sun Jun 19, 2005 11:13 am
Forum: General Discussion
Topic: ADC signal into PLC
Replies: 8
Views: 2048

Re: ADC signal into PLC

re: scaling and offset with Op Amp: read chapter 4 of "Op Amps For Everyone", a free book you can download from www.ti.com. The main emphasis is single ended rail-to-rail op amps which do a great job of feeding in to controllers which typically have a fairly low input impedance.<p>For example, it is...
by rstofer
Fri Jun 10, 2005 9:37 pm
Forum: General Discussion
Topic: pic pwm feasible?
Replies: 7
Views: 1762

Re: pic pwm feasible?

Well, now you are doing PID control (Proportional, Integral and Derivative) although one or more terms may be omitted.<p>What you are asking for is an output that is proportional to the error (or difference) between a set point (stick position) and a control point (or current position). The larger t...