Jim:
In some cases, soldering an IC into the circuit substrate or printed
circuit board reduces the inductance of critical I/O paths to/from the
chip. Moreover, soldering an IC down is cheap, and it ensures a measure of
reliability that a separable interconnect cannot provide. However, if you
can tolerate the longer lead lengths in your circuit, in a ham radio
project, having the ability to swap ICs easily in sockets means it's often
easier to substitute parts and check and repair circuits.
I would NOT suggest using simple edge-wipe sockets such as those found at
Radio Snack however. They're often more trouble than useful! Try to find
some screw-machined DIP sockets. They're also known as high-rel types (high
reliability). At the actual interface between the lead frame of the DIP (
its leads), and the socket, these connectors form what's called a gas-tight
seal. There's actually a migration of atoms from metal-to-metal that causes
a connection which is as good as wire---and won't permit corrosive gases to
enter and wreak havoc.
Have fun! Vy 73, AI2Q, Alex in Kennebunk, Maine .-.-.
----------
> From: Jim Lowman <jmlowman@ix.netcom.com>
> To: Simmons, Reid W <reid.w.simmons@intel.com>; tentec@contesting.com
> Subject: Re: [TenTec] QRP T-Kits and IC sockets
To: <tentec@contesting.com>
> Date: Sunday, August 02, 1998 1:07 PM
>
>
> At 03:19 PM 7/24/98 -0700, Simmons, Reid W wrote:
> >
> >A recent post plus several previous messages on this subject prompted me
> >to post this.
> >
> >I recently built the 1320 QRP CW transceiver and, contrary to the
> >sometimes strongly worded advice against it both in the manual and on
> >this list, I USED SOCKETS at EVERY IC LOCATION! The reasoning behind my
> >"outlandish display of rebellious behavior and a total disregard for
> >established practice" was that I HATE to unsolder defective ICs, it
> >makes experimental substitutions a snap, circuit modifications will be
> >far easier, and... because there really is sufficient room on the
> >circuit board to do this.
>
> OK...anyone know what is the conventional wisdom WRT using/not using IC
> sockets?
> I recall that many of the Heathkits that I built in the 1970s had sockets
> supplied for each IC.
>
> I'm one of these guys who will listen to reason, but I hate to see advice
> without
> some thorough background.
>
> It's just a straight-though connection, and certainly facilitates repair.
> Where's the problem?
>
> Thanks in advance and 73 de Jim - AD6CW
>
>
>
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