Learning to PLAY in 2020

Because of the calendar placement of the Christmas and HNY holly daze, I've spent a considerable amount of contest down-time @W7AYT's QTH - PLAYing; yes, Playing - adults are just overgrown kids with BiGGer and more Expensive ToYs.

A revamped ICOM-7000 and a Classic Moscow Muffler have been recently added to the "portable" equipment lineup @W7AYT.  As wonderful as the Muffler is, I need to remember that because it works BE-4 the RX's front-end, it is absolutely worthless in treating the Woodpecker when it obliterates NX6T's passband; ironically, the 10-hz radar is rarely/weakly heard @W7AYT in
the SF East Bay area.

In preparation for last weekend's RTTY RU GiG, I have been playing around with cable and equipment configurations.  The 8JK Inverted Vee is for-now producing consistent results, so
I am leaving it alone.  (104 QSOs in the Stew Perry 160 GiG is proof this 8JK configuration is producing.  With the 8JK sloper configuration, as I recall only 6 local QSOs were possible in
the July 160 contest).

Thanks to the 500+ memory system in the ICOM 7000, the transceiver is being utilized mainly as
an SWL receiver; with the provision to switch in the Muffler at any time.  Ironically (or should I say thankfully), the 200+ already programmed memories were still intact when the radio made it's first
trial run in Concord (after a trip to the ICOM repair center).

While both the ICOM 7000 & FT-1000mp utilize state-of-the-art receiving circuitry, the MP is more optimized for ham band operation, designed secondarily for the frequencies in between.  Contrast
this with the 7000 which is entirely DSP-based and works reasonably well on virtually any frequency between 50-khz and 30-mhz (plus 2m & 440).  Listen-wise, I find that it is easier to locate and memo frequencies using the IC-7000, then later enjoy each station on the FT-1000mp, with it's far superior audio response. 

Having multiple sources of RX requires an elaborate switching arrangement with judicious use of isolation filters to reduce the AC-hum and mitigate overload effects of stray RF in the stereo audio stream.  An advantage to using UHF-based wireless headphones is their overall immunity from
HF-Rf.  For this year's RTTY RU contest, to integrate the K3/0 (remote) audio with "local" audio
from the FT-1000mp (direct & filtered) as well as the IC-7000, I utilized a 4 device 1/8" mini-switch.

For a more pleasing sounding RTTY experience, Autek QF-1A filters (one for each ear) were peaked for the MARK (Left) and SPACE (Right) frequencies.  When a station calls in EXACTLY on frequency, the audio tones resonate perfectly with each ear; if not, the R-i-T control can easily remedy that situation - when F3 is pressed ("TU QRZ?") the N1MM software resets the RX-offset back to
ZERO, ready for the next caller.

Before each external add-on unit is given a test run @W7AYT in Concord, I work out configurations
at my QTH in Alameda.  As you can see (above) the 1/8" switch is being tested in conjunction with an Autek QF-1A (L. Ear) and an MFJ-751 (R. Ear).  The switch allows sending the stereo audio directly to the headset, or thru the filter-set, as well as the I-Sound speaker-set.

It could be said that a significant amount of circuitry (and knob-twiddling) is being devoted to reducing unwanted interference (be it QRM or QRN based) or otherwise "shaping" the audio to raise the signal-intelligibility.  While cascading audio filters can make a BiG difference, feedback-based units (ex: Autek QF-1A and MFJ 751/752) can create such a high degree of amplification that eventually results in audio-howling.  However just prior to those excessive settings, high-Q selectivity can be attained.

Remember: All these devices are used to recover audio quality AFTER it has been "destroyed" by overloaded RF/IF stages and AGC circuitry.  Front-end devices like the Moscow Muffler as well as
the MFJ-1026 & JPS ANC-4 noise phase inversion units exist to eliminate the problematic noise BE-4 it makes it to the more-easily over-loadable RF front-ends of most receivers.

These are just a few radio things I have been "Playing around With" recently. 
As I continue with "play mode", LooK for random notes to appear throughout this BLOG.

Do YOU Play with YOUR Radio Equipment?

IF NoT - Why KNOT?