KC-1 keyer/counter

---------

From: Arjen Raateland, SYKE/YV, puh. 90-4030 0457 (Arjen.Raateland@vyh.fi)
Date: Fri Sep 22 1995 - 11:17:37 EDT


My KC-1 from Wilderness Radio arrived a few days ago. No hurry to
assemble as I'm waiting for a Sierra from the same place.

On studying the documentation and reading the article by the designer
of the KC-1 in QRPp I noticed that the current version of the KC-1 has
done away with the divider IC (something like 74HC..20).

When I look at the PC board I wonder how a second IC ever might have
fitted, but there must be an other reason for not having the separate
divider IC ;-) The KC-1 certainly is a very smart design. I remember
that the designer mentioned in a message to this group that he had an
unused output on the PIC IC. In the kit I got there is an auxiliary
switching output for anything the user cares to switch. So thoughtful!
One would expect this to be a very succesful product.

I have a suggestion to make to anybody who builds the KC-1. The
regulator 78L05 takes about 4 mA of quiescent current. It could be
replaced by a similar regulator IC LP2950 that has only 75 microAmps
quiescent current, but similar maximum load current data as a 78L05.
Four milliamps is still a lot of current to waste if the total current
consumption of a rig is only 35 mA!

Unfortunately I haven't been able to get any LP2950's yet, but for
small CMOS circuits like the KC-1 they should be just the thing to
use.

73 de OH2ZAZ

Arjen Raateland
Suomen Ymp rist nkeskus / YV
--... ...-- -.. . --- .... ..--- --.. .- --..
Finnish Environment Agency, Helsinki, Finland
SAS Support
EMAIL: Arjen.Raateland@vyh.fi
tel. +358 0 4030 0457
fax +358 0 4030 0490
.-.-. -.-


Search QRP-L Archives

[ QRP-L Archive | ]
[ 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 ]

---------

This archive was generated by hypermail 2b29 on Fri Jun 02 2000 - 11:28:33 EDT

kd4ab@kd4ab.org