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Array Solutions (AS-AYL-4C) K9AY Loop System Control Box Indoor Unit Only

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MPN:
AS-AYL-4C
Condition:
Used
Shipping:
$8.00 (Fixed Shipping Cost)
  • Array Solutions (AS-AYL-4C) K9AY Loop System Control Box Indoor Unit Only
  • Array Solutions (AS-AYL-4C) K9AY Loop System Control Box Indoor Unit Only
  • Array Solutions (AS-AYL-4C) K9AY Loop System Control Box Indoor Unit Only
  • Array Solutions (AS-AYL-4C) K9AY Loop System Control Box Indoor Unit Only
$34.99
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Description

Array Solutions (AS-AYL-4C) K9AY Loop System Control Box Indoor Unit Only.

 This unit power up. I have not tested it beyond that. It looks to be in Excellent Condition.

I am selling it as is, as described for parts repair or to use as it is.

 

The Array Solutions (AS-AYL-4C) K9AY Loop System control box is the indoor "shack" unit of the discontinued commercial 4-way K9AY terminated loop receiving antenna system (originally designed by Gary Breed, K9AY, and sold by Array Solutions as the AS-AYL-4; the essentially identical version was also offered by AY Technologies as the AYL-4). It pairs with a separate outdoor relay/switching box (AS-AYL-4R or equivalent) via a 6-conductor control cable and coax feedline.
 
arraysolutions.com
Key Features and Specs (from manufacturer manuals)
  • Front panel controls: 4-position direction switch (selects one of the four cardioid patterns by controlling the outdoor relays), 8-position rotary switch for termination resistance (steps from ~340–680 Ω to optimize front-to-back ratio per band/ground conditions), preamp on/off switch.
  • Built-in electronics: 15 dB preamplifier (feedback-type silicon NPN transistor) + bandpass filter (nominally 1.8–5 MHz with preamp on; ±2 dB passband, strong rejection of AM broadcast band below ~1.45 MHz and signals above ~5–7 MHz).
  • Connections:
    • SO-239 (UHF) for coax from the outdoor relay box.
    • Phono (RCA) output to your receiver’s external antenna jack.
    • 6-pin connector (or terminal block on some units) for the control cable to the relay box.
    • 2.1 mm DC power jack for +12–15 VDC (draw ~400 mA max with preamp on; internally fused).
  • Purpose: Low-band (primarily 160 m and 80 m, usable on 40 m) directional receive antenna with excellent noise rejection and F/B ratio (typically >20–30 dB). The preamp helps compensate for the loop’s inherent loss while the filter keeps strong out-of-band signals from overloading receivers.
  • Notes: The control box does not include the outdoor relay box, antenna wires/loops, mast, or radials. It is strictly the indoor controller/preamp unit. The full AS-AYL-4 system was popular in the mid-2000s for low-band DX/contesting where space for Beverages was limited.
The product is long out of production (Array Solutions and AY Technologies pages still host the manuals, but it is no longer actively sold new). It is a well-regarded, solidly built piece of ham gear with quality PCBs.
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