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KB2VXA > AM 29.05.03 00:04l 71 Lines 3402 Bytes #999 (0) @ WW
BID : 8196_WT3V
Read: GUEST DB0FHN
Subj: Re: VK3ABK > Quality AM
Path: DB0FHN<DB0RGB<DB0MRW<DB0SON<DB0ERF<DB0FBB<DB0GOS<DB0EEO<DB0RES<ON0AR<
VK6HGR<VK3TE<KB2TXP<KB2FAF<WB2VPY<WA3LWR<W2LV<KB2VLX<KC2COJ<WT3V
Sent: 030528/1910Z @:WT3V.#CNJ.NJ.USA.NOAM #:8196 [Lakehurst] $:8196_WT3V
From: KB2VXA@WT3V.#CNJ.NJ.USA.NOAM
To : AM@WW
Hi Dick and YAYemmers,
NOW YOU'RE TALKING MY LANGUAGE!!! Around here YAY em (YAY YAY YEALO!) is
considered Angel Music! They use everything from modded out old boat
anchors to homebrew to AM broadcast transmitters. Receivers are just
about anything with sufficient IF passband and audio chain and of course
a HWHY FI speaker. Pardon my Timtronese, I'm a fan of The Timtron, WA1 H
YELL R and his famous band of brigands in the 75M AM slot.
7290 +/- is a popular daytime frequency with LOTS of activity, the AM
slot on Top Band is the home of quite a few 1KW broadcast transmitters,
they need no modification, just retuning and proper crystals. There used
to be a lot on 10M but with the band going out of course all activity
except the local chatterboxes.
Yes, AM is alive and well and there are several clubs dedicated to it.
Hmmm, a little humorous nit picking I see! OK, SSB is technically lop
sided AM. Then again several SW broadcasters use SSB with carrier. High
power AM transmitters these days use PWM and you can't hear the
difference, well, it comes OUT as AM. Collins had an interesting
modulation method, dual PM. They fed phase modulated signals into
properly spaced antennas and the signals combined to produce AM OUTSIDE
the transmitter. RCA had a similar system that worked inside the
transmitter, the BTA-50R Ampliphase transmitter was the proverbial
workhorse in it's day because it didn't have power consuming push-pull
modulators. It was a bugger to keep in tune though. (;->)
Just as a footnote, a few Hams around here transmit compatible AM STEREO.
For example, one has a Kahn system which was one of the early "beta
tests" before the Motorola system became the standard. It transmits
separate audio on each sideband with carrier, and can be adjusted to
emphasise one sideband, thereby protecting an adjacent frequency. Some
broadcasters use this system to protect another broadcaster from undue
splatter. Now THAT comes in handy in those crowded AM windows!
Oh yeah, the constant gripe is those SLOP BUCKETEERS who have a blatant
disregard of the AM windows. This garbage has been going on since Art
Collins proved SSB to be a viable mode and there are some Hams who are
completely disrespectful (in a whole LOT of ways).
Now if you want REALLY hi-fi audio, try WBFM on 70cM. At one time I
consifered transmitting standard stereo modulation as an experiment, but
found the majority of the Hams I spoke to had no idea how multiplexing
works and of course would never figure out how to demultiplex an ordinary
stereo composite signal. I figure they never looked in the back of the
RCA tube manual (or the solid state one) and built an FM stereo receiver
from scratch. Yeah, could have bought one off the shelf and already had
several of them BUT I like a challenge. BTW, cascade Nuvistors STILL make
the best 2M preamp around! Uh huh, it was called the RCA "Golden Cascode"
and gave birth to several product lines including some of the best TVs
ever.
Oh geez, NOW look at what you have me doing! If I don't stop now I'll
burn up the BBS. Byeee...
73 de Warren, KB2VXA @ WT3V
E-MAIL: kb2vxa@juno.com
**************************************
Preserve the integrety of our network,
stop Internet forwarding!
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Message timed: 19:16 on 2003-May-28 GMT
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