Hi Gene,
Just a quick note to say how much I enjoyed reading your ebook on
receiver building.
Our careers seem somewhat parallel. My first electronics lesson was
about 1950 at the age of 8 when my ray gun broke. My dad demonstrated
how a complete circuit was needed brm the battery to the light bulb to
make it light. About age 12, the family radio was replaced with a
radio/phonograph, and I got to keep the old Truetone radio, which had
short wave coverage. Discovered hams and short wave broadcasting.
Tried several times to learn CW to get a ham license, but couldn't
master it. Unfortunately, when I joined the Navy that learning attempt
allowed me to score high on the CW aptitude test in spite of very low
ability and I was made a Radioman for my guaranteed electronic
education. Somehow CW was a little easier to learn going 4 hours a day
with a CPO leaning over my shoulder. Was doing 22 WMP by the end of RMA
school while the rest of the class was at 26 or better. First duty
station was one of the 120 radioman assigned to Commander 7th Fleet,
homeported Yokosuka, Japan. 4 section duty, in port or at sea, 2 days on
and 2 completely off, fantastic. In my entire 4 year Navy career,
1962-1966, sent only one message by CW. Got out of the Navy in San
Diego and got a job as an electronic tech at Wavetek, although knowing
only tubes, not transistors.
73
John
KK6IL
http://www.jlkolb.cts.com/
| 10621
| 2014-12-17 15:33:09
| Gene W5DOR
| Re: my ebook on building a receiver
|
I looked at the pix of your shack/workbench in detail and recognized the 8640B signal generator and the R390A receiver. I was on the USS Bushnell where each CW position included a R390A receiver. WE were docked in Key West, Florida my whole tour of duty and had to put up with nice weather, and having to make tough decisions each day like "shall I go fishing, scuba diving or just lay on the beach". The ship only got underway about twice a year for a week or so. We sailed up to Mardi Gras several times. We hams were encouraged to take whatever surplus or obsolete radio gear we could use. The Navy supported our ham activities very well. We had a new Collins HF 1kw transceiver down in the transmitter room that I could use on the ham bands. Our ship was licensed as WA4KMH/MM. We US Navy Radiomen used CW a quite a bit because we still considered it the most reliable means of communications. We monitored the Navy CW broadcast from WashDC which sent CW messages to the submerged submarines (boats). With a long wire antenna a submerged boat could copy that broadcast that was transmitted on 15KHz with the megawatt transmitter in VA. Yes, 15KHz is correct. When I worked at TI I had a new engineer just out of school that heard me tell about those VLF broadcasts and he proceeded to tell me I was wrong because at 15KHz it would hurt everyone's ears. I don't know if I every convinced him that there was a difference between sound waves and electro-magnetic waves. ;-) Well, I'd better get busy here at the workbench. 73, Gene, W5DOR gene@w5dor.com www.w5dor.com
| 10622
| 2014-12-17 16:09:48
| John
| Re: my ebook on building a receiver
|
Well, my workbench hasn't looked like that in many years, Besides the changes in equipment, it's piled a foot deep in unsorted parts, etc. Far too much work to clean up to take an updated photo. Your ebook mentions the PHSNA project. I've built one and it works well on mechanical filters but doesn't really have the dynamic range to show ultimate rejection. Is a lot better that measuring filters manually point by point however. I've long had an interest in receivers and in mechanical filters. There's discussion in the PHSNA group today on a version of it which would be a full vector analyzer. I went through a lot of different receivers in the '70's as an SWL. Among those was a R-389, the VLF/LF/MF version of the R-390. I remember hearing NAA, 2 megawatts, down around 14 kHz, but the msgs were all 5 character crypto groups so uninteresting to copy. I did get QSL cards from WWVB and WWVL on 20 and 60 kHz. Ah, new engineers just of of school - I had one once, with a masters degree. He could solve anything he had ever had in school, but Lord help you if you gave him a new task. I was supposed to train him to replace myself but he had trouble winding low ohms resistors we were making for trim R's in a precision voltmeter/calibrator. John
| 10625
| 2014-12-17 18:06:48
| wb8yyy_curt
| Re: my ebook on building a receiver
|
Gene
thanks much for sharing your wealth of info. I have been dialoging with a recent ham and your eBook greatly extends what I have been sharing,
73 Merry Christmas
Curt WB8YYY
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