> If the 'regular' contacts are the same as what was previously > supplied with the various Begali magnetic paddles, they have > problems with many keyers, including the K2's internal keyer, > the Logikey, and others. So the gold contacts are a very good > investment.
The "issue" with the regular Begali contacts (as well as those used by Schurr and others) is that they appear to be of an alloy that forms a semi-conducting surface. That results in contacts with a minimum voltage drop - independent of current - of around .5 volt. That 1/2 volt offset is too high to allow low power CMOS inputs (e.g., Logikey and others) to reliably register a logic "Low" and is enough of an offset to upset the decision point on PIC based keyers with a multiplexed (analog) paddle input (e.g., WinKey and others). The solution is to add a schmidt trigger inverter and FET driver (or dual comparator) in line with each paddle contact. 73, ... Joe, W4TV > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Vic K2VCO > Sent: Friday, October 26, 2007 12:18 PM > To: Chris Wagner > Cc: [email protected] > Subject: Re: [Elecraft] recommendation of a low cost iambic > paddle / BeengaliSimplex shipping with gold contacts > > > Chris Wagner wrote: > > I ordered the regular Simplex and paid a few bucks > > more due to making an EU payment. Anyhow, they will > > send me the model with the gold contacts as this is > > the one they have in stock, while the regular contacts > > will be manufactured in a few weeks. So if you plan to > > get one of these, ask if you could get the upgrade. > > If the 'regular' contacts are the same as what was previously > supplied > with the various Begali magnetic paddles, they have problems > with many > keyers, including the K2's internal keyer, the Logikey, and > others. So > the gold contacts are a very good investment. > > If you're interested in details see my review of the Begali Magnetic > Professional, about the 5th one down at > <http://www.eham.net/reviews/detail/3468>. Other than the non-gold > contacts, I love this paddle. > -- > 73, > Vic, K2VCO > Fresno CA > http://www.qsl.net/k2vco _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
