[Moon-net] Help find intregrated circuits

[Chris Bartram]

Hello Ken

> Can anyone help me find a 4040 ripple counter and a Siltronics 2102 memory
> chip please?   Both are very old chips, but the alternative will be much
> re-working of my memory keyer which has given up after years of service..
> Can't find either of these chips in suppliers lists. Thanks,

The 4040 is now called the 74HC4040, and is available from RS amongst other 
places. The only difference is that unlike 'real' 15V 4000 series CMOS is a  
5.5V supply limitation, however if your keyer operates from 5V that will be 
OK.

The 2102 was, if I remember aright, a 1k static RAM chip. You'd probably find 
that difficult to locate now, although it might be worth a hunt around some 
of the vintage computer websites - there are guys who enjoy building archaic 
computers for fun!! There's a market for obsolete chips, but don't get 
caught-out by the big dealers who'll try to charge $100 - 200 for a part. 
You'd probably find that you could make a little adaptor board and use a 
modern static ram chip. If you just address the lines you need, and ground 
the others, then it should work OK. You'd need to look at data sheets to see 
what's involved.

Hope you're well. I've noticed you on 'KST a couple of time since I got my 
antennas in the air again - they were down all winter. If you'd like a sked 
on 23, I have a simple system (~60W to a single 21dBi yagi) and I'd be 
delighted to have a try. Since coming back on, my QSOs have included a couple 
of 1000km+ contacts on 1296 and similar results on 432. The jewel has been 
CT3 by tropo on 2m...

Vy 73

Chris
GW4DGU

-- 
Christopher Bartram MIET
Christopher Bartram RF Design
Blaenffos
Pen-y-Bont
CARMARTHEN
SA33 6QG

phone:  	+44 1994 484650
mobile:		+44 7968 193555
email:  	chris at chris-bartram.co.uk
URL:		www.christopherbartramrfdesign.com