Search found 5 matches

by bill_s
Sat Mar 12, 2005 1:59 pm
Forum: General Discussion
Topic: phase shift
Replies: 3
Views: 1023

Re: phase shift

We need more specifics, like the range of frequencies that have to be phase shifted, and the number of degrees needed, and the tolerance in degrees and dB.
by bill_s
Sat Mar 12, 2005 1:39 pm
Forum: General Discussion
Topic: serial comm noise problem
Replies: 14
Views: 2645

Re: serial comm noise problem

A couple things. The RS232 spec allows a +- 3 volt noise band, and is supposed to have this much hysteresis built into the receivers, but there are some non-standard implementations out there, where the receiver is just a TTL or CMOS gate. OK for across the desk, but suspect for long runs. If your 2...
by bill_s
Fri Mar 11, 2005 7:39 am
Forum: General Discussion
Topic: serial comm noise problem
Replies: 14
Views: 2645

Re: serial comm noise problem

Put a scope between the grounds on your separate floors and you will get an idea of the common-mode noise you have to deal with. This noise will be complicated by any multiple tying of neutral with ground in your building, which may give you extra-big spikes when heavy loads are started.<p>But the b...
by bill_s
Tue Mar 01, 2005 9:32 am
Forum: General Discussion
Topic: surging GM alternators
Replies: 20
Views: 3241

Re: surging GM alternators

I think Terri got it right. I've had two Ford regulators do this, only at idle, and one was only in the car for a few months. In both case, they worked properly off idle, and I don't consider it a problem. My guess is that they are using an electrolytic in the feedback path, and the high temps (regu...
by bill_s
Tue Mar 01, 2005 6:17 am
Forum: General Discussion
Topic: BasicStamp2
Replies: 10
Views: 2450

Re: BasicStamp2

Depends on what your time is worth. The BS2 is a well thought out device with excellent programming support and a right-now code modify-test cycle. You pay for this with the cost of the chips. You don't really need the development boards; no external active devices are needed; power, ground, a DB9 f...