From: a-kevinp@microsoft.COM (Kevin Purcell, Rho)
Newsgroups: rec.radio.amateur.misc
Subject: Highest frequency QSO
Date: 30 Dec 92 17:34:52 GMT
Organization: UCSD Usenet Gateway
NNTP-Posting-Host: ucsd.edu
Originator: daemon@ucsd.edu

Sometime ago I asked what was the highest frequency (two way) QSO 
(excluding laser contacts). I got the following replies:

Lynn Hurd, WB7UNU, said:

Tom Hill (WA3RMX) and myself (WB7UNU) have carried on a QSO
on 47 GHZ. Tom is now working on 80 GHz rigs for the small
band we have there.

Tom and I did hold the 24 GHz distance record for the U.S. a
few years back.  We did a 185 mile path with 3 milliwatts and
28" dishes. Mount Hood to Paulina Peak in central Oregon.

Tom and Roger McCoy (W7ADV) held the 47 GHz distance record
for a while (in the U.S.). I believe it was about 5 miles.

During field day a year ago, the Tektronix Ham Club put on 41
transmitters for Field Day. That's 160 Meters through 474 THz.
We think that was a record, but we received no mention in QST
other than our log entry and score, even though we sent an
article and pictures along with our score sheet.  Ah well, we
usually are ignored here on the West Coast.

I received your response.  The 24 GHz and 47 GHZ (and the future 80 GHZ)
are all sideband rigs.  We need the improvement one gets from SSB.

By the way, our 41 transmitter operation was also done entirely on
emergency power! so we were 41E Oregon! And by the way, the rules
state that the transmitters all need to be on simulatneously to count.
That was an interesting problem in logistics!

All the rigs were done with very stable LO's mutiplied up, and finally
put into waveguide mixers with a VHF mulimode rig on sideband, then
filtering to pass only the product of interest on to the amplifier (if
any) or directly to the horn or dish antenna. a 10" dish was used on
47 GHz.
-----------------------------------

Hugh Wells,   W6WTU said:

This may not qualify as a communication, but while at the University of
Illinois in 1958-59, I developed solid state frequency multipliers that allowed
me to generate CW energy in the 164 and 264GHZ range at 8-12mw.  As part of
this work, I developed diode detectors for these frequencies as well.  During
this period, I would frequently transmit my call sign from one end of the lab
to the other.  The modulation modes used were FM and CW.

The work was very interesting in that it extended my knowledge of ultra
microwave energy and the components that support it.  At that time, waveguide
components for 164-264GHZ were not available and therefore had to be hand made
and/or electroformed.  Some hand made bolometers and Golay cells from that work
are still being used at the University.
-----------------------------------

Henry KB7NIE said:

Here is a list of the highest frequency QSOs as listed in
THE ARRL UHF/MICROWAVE EXPERIMENTER'S MANUAL

Frequency            Distance(km)     Stations                Date
 432 MHz             4151             XE2GXQ-KH6HME           1989 Jul 15
 903 MHz             1003             WB5LUA-W4ODW            1988 Mar 22
1296 MHz             4151             XE2GXQ-KH6HME           1989 Jul 15
2304 MHz             1883             VK5QR-VK6WG/p           1978 Feb 17
3456 MHz             1885             VK5QR-VK6WG             1986 Jan 25
5760 MHz              981             G3ZEZ-SM6HYG            1983 Jul 12
  10 GHz             1660             I0SNY/EA9-I0YLI/IE9     1983 Jul 8
  24 GHz              331             I0SNY/IC8-I8YZO/8       1984 Aug 11
  47 GHz              105             WA3RMX/3-K7AUO          1988 Aug 6
  76 GHz                0.5           HB9AGE/p-HB9HIN/p       1985 Dec 30
 120 GHz     No Reports
 142 GHz     No Reports
  .
  .
  .
 668 THz              248             KY7B/p-WA7LYI/p         1991 Jun 7

The last line was a laser shot and that information comes from the
September 1991 CQ magazine.
--------------------------------------

Thanks for the replies

73 de Kevin Purcell N7WIM/G8UDP (Seattle, WA)          a-kevinp@microsoft.com
Do your interests match mine? If so call me. I'd like to hear from you.
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