Yes, screw-machined sockets would have been the better choice
particularly if the unit is to be subjected to corrosive environments
(salt air, high levels of pollution, etc.). My workshop supply of these
was out of them (and 8-pin sockets in general) and RS was the only
supply open that late on a Friday night.
Reid, K7YX
______________________________ Reply Separator
_________________________________
Subject: Re: [TenTec] QRP T-Kits and IC sockets
Author: "Alex Mendelsohn" [SMTP:alex.ai2q@worldnet.att.net] at MSXGATE
To: <tentec@contesting.com>
Date: 8/3/98 6:57 AM
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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