[Elecraft] K2, distorted audio signal

[Fred Jensen]

"It is amazing how we were able to build radios with only 2 sided PCBs 
for 50 ohm micro or strip lines."

In the later 70's we took delivery of a Data General Nova 3 
mini-computer that came with a FORTRAN compiler.  The circuit boards 
were 15" square-ish, 2-layer.  We quickly discovered that periodically 
but unpredictably, execution of the compiler would quit dead on a DO 
statement in the source.  It just stopped.  No other statement, only a 
DO and not all the time, but if it stopped, it did so on every recompile 
of that source. <mailto:elecraft at mailman.qth.net>

After several DG visits they finally believed us and showed up with 
their Guru in flip-flops, ragged board shorts, a torn T-shirt, and 
fairly long-ish uncombed hair.  He said almost nothing and the other 3 
DG's [in "computer expert" business attire] were very attentive to him. 
<mailto:elecraft at mailman.qth.net>

He spent most of the morning with the 'scope making notes in a beat-up 
notebook in indecipherable script and diagrams.  Finally muttered 
something to his minions who raced to get him an Xacto knife, some very 
light insulated wire, and the soldering station.  He cut both ends of 
several parallel traces and replaced them with twisted pair jumpers. The 
compiler never stalled on a DO statement again.

Problem likely would never have occurred had the board had a 3rd ground 
layer between the two outer ones but they they had yet to be invented.

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County



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