W4XKE Johnny
Hi, I'm Johnny from United States (US) EM75LW, radio amateur with W4XKE callsign.
Many thanks for coming to my web page.
Hope to hear from you soon, 73's Johnny
MFH stats: 0 QSOs • 0 eQSL • 0 Spot
The known position of W4XKE
Who is W4XKE
Prevailing antennas here are a 40 Meter
Delta Loop and a Half Square, oriented with the lobes north-south from
Crossville, Tennessee, USA. Before retirement I worked in the prototype development
laboratory for Delco - Hughes G.M. Electronics Division and part of the
work centered around building proto boards on our Philips MCM-VII
placement machines manufactured in the Netherlands.
One thing that unnerved me a bit was that
all of our reels of surface mount chips had to be date-coded not to
exceed 1 year of age. Any reels (Siemens, RCA, Mitsubishi, Philips, NTE,
Motorola, etc.) of chips older than 1 year in our inventory had to be
destroyed. I asked one of the Philips engineers about it one day,
wondering if we could expect electronic equipment failures after a
year's service. (???)
He explained that the expiration date had to do with the 'solderability' of the components - not on their life expectancy. The oxidation present on their contacts caused reliability problems in the continuity - usually in the wave-solder operations. I thought that was particularly interesting.
I remember trying to change an op-amp in an older Radio Shack HTX-202 and I had a terrible time with solderability issues and finally caused the traces to lift off of the circuit board before losing the battle. Old solder joints can be a veritable challenge to reflow and repair!
He explained that the expiration date had to do with the 'solderability' of the components - not on their life expectancy. The oxidation present on their contacts caused reliability problems in the continuity - usually in the wave-solder operations. I thought that was particularly interesting.
I remember trying to change an op-amp in an older Radio Shack HTX-202 and I had a terrible time with solderability issues and finally caused the traces to lift off of the circuit board before losing the battle. Old solder joints can be a veritable challenge to reflow and repair!
Information on W4XKE
Country: United States
TZ Offset: -5 hrs UTC
DXCC: 291
ITU Zone: 3, 4, 5
CQ Zone: 6 ,7 ,8
Callsign: W4XKE
ID DMR:
First Name: Johnny
Other information is only visible to registered radio amateurs
