On 08/25/2013 06:31 PM, Andy Ikin wrote:
Charlie,
When I was poor man 40 years ago, I always wanted Tektronix 545B
Scope, which I couldn't afford. So I built a "Chinese Copy" with
discarded parts from the Calibration department of the computer
company I worked for. The scope use many 6DJ8s. I did get it working
after about a year; not bad for some one with no formal electronics
training!!!! Tektronix were very helpful in supplying some critical
parts. Looking back I must have been mad, but it was one hell of away
to learn how these things work.!!!!
Bye the way I manufacture a special Head Amplifier for the KAZ and
other Flags. This has 1100 Ohm input matching/isolation transformer,
about 20dB gain and a less than 1dB NF and uses 8 x J309s plus a
string of 1N4148 limiting diodes. Wellbrook FLG100LN. There are about
70 units in service mainly in the US with MW Dxers.
73
Andrew G8LUG
Hi Andrew,
When we build our own gear we do learn a lot. The first gear I built was
a V-O-M in a cigar box. I was around about 13 and somebody gave me meter
movement. Cigar boxes were free and so were junk televisions and radios.
The ARRL handbook was over at the library. I didn't have a mode switch
or a range switch but plugged resistors into an octal socket to make up
each mode/range. I used it for almost two years before I got a *real*
V-O-M. The real one was a little more accurate and a lot more convenient
to use. But to this day I am familiar with how voltmeters work! That was
about 50 years ago... I'm 66 now.
73,
Bill KU8H
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Topband Reflector
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