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Re: Topband: 2-element receiving arrays

To: Frank W3LPL <donovanf@starpower.net>
Subject: Re: Topband: 2-element receiving arrays
From: VE6WZ Steve <ve6wz@shaw.ca>
Date: Thu, 30 Mar 2023 18:29:15 -0600 (MDT)
List-post: <mailto:topband@contesting.com>
I strongly second Franks comment about weather proofing.

Equally important on any outside electronics is to very carefully clean ALL the 
residual flux off the PC boards, and especially on the F-connector solder pads.
ALSO, apply some acrylic conformal coating on all outdoor PCBs.

With 12v on the coax line with a bias-T setup, even small amounts of dirt stuck 
to old flux and then combined with moisture can cause serious noise issues with 
micro conduction between the centre conductor and ground pads.

I have since redesigned all my rx amplifiers to use a separate 12v dedicated 
supply voltage to keep the DC off the coax.

73, Steve Ve6wz

Sent from my iPad

> On Mar 30, 2023, at 2:18 PM, Frank W3LPL <donovanf@starpower.net> wrote:
> 
> Tiler, 
> 
> Congratulations on your new five circle YCCC array! 
> 
> Be sure you very effectively waterproof all of your coaxial cable connectors 
> that carry DC power. Even the slightest amount of moisture in the connectors 
> will cause micro-arcing of the DC voltage, raising your noise floor by many 
> dB. 
> 
> 73 
> Frank 
> W3LPL 
> 
> 
> From: "K3MM" <k3mm@verizon.net> 
> To: "Frank W3LPL" <donovanf@starpower.net>, "topband" 
> <Topband@contesting.com>, "PVRC" <pvrc@mailman.qth.net> 
> Cc: "Pete N4ZR N4ZR" <pete.n4zr@gmail.com> 
> Sent: Thursday, March 30, 2023 8:08:42 PM 
> Subject: Re: Topband: 2-element receiving arrays 
> 
> I just completed building a YCCC nine Circle array using V E6WZ PC boards 
> with the latest mods, including on board chokes. I actually have it deployed 
> currently as a five circle As I’ll be taking it down soon for mowing season, 
> but it works quite well. The patterns on all three bands, 160 through 40 are 
> as advertised. Very good patterns but not the best sensitivity . I built mine 
> as about 23 foot verticals. I’d say compares favorably to my 500 foot 
> beverage, antennna although it requires a lot of pre-amplification. Due to 
> the active electronics it can be overloaded by close transmit antennnas so 
> perhaps not as useful for a multiband operation in a small area. 
> I’m providing power over the coax cable and using green heron everywhere, 
> wireless remote control, which works quite well and is controlled by the PC 
> software using a mouse or hotkeys. 
> 
> It was a fun project. It turned out quite well, but not in expensive. I 
> scrounged about half the aluminum tubing and angle I’m using for the bases 
> and probably spent $1500 or so. including the remote control hardware. next 
> fall, I’ll deploy the full nine circle array, but the five circle is probably 
> almost as useful and avoids some complexity and cost. i’ll also probably 
> relocate it to get more separation from some of the transmit antennnas. 
> 
> Ty K3MM 
> 
> [ https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661 | 
> Sent from the all new AOL app for iOS ] 
> 
> 
> 
> On Thursday, March 30, 2023, 1:38 PM, Frank W3LPL <donovanf@starpower.net> 
> wrote: 
> 
> 
> Hi Pete, 
> 
> For a monoband receiving array, you might consider using low impedance 
> resonant verticals rather than high impedance verticals. 
> 
> The primary advantages of high impedance verticals are 
> - very short verticals (but taller verticals produce stronger signals) 
> - multi-band operation 
> - no radials 
> 
> The primary disadvantages are 
> - reliability issues with outdoor electronics 
> - lightning susceptibility of outdoor electronics 
> - higher cost 
> - much lower signal levels 
> - extreme care required to suppress common mode signals (buried feedlines are 
> highly recommended) 
> - negative effects of nearby trees and buildings. 
> 
> The primary advantages of low impedance verticals are 
> - much stronger signal levels 
> - much less criticality of common mode signal suppression, 
> - much lower cost 
> - much higher reliability 
> - immunity to lightning damage 
> - much less affected by nearby trees and buildings 
> 
> The primary disadvantages are 
> - taller verticals (typically about 24 feet) 
> - radials (they can be very short if many radials are used) 
> - mono band operation (switchable matching networks can be used for 
> multi-band operation). 
> 
> I highly recommend the DX Engineering Receiving Antenna Phasing System. 
> Its expensive but well worth the investment especially for a small array. 
> 
> [ https://www.dxengineering.com/parts/dxe-ncc-2 | 
> https://www.dxengineering.com/parts/dxe-ncc-2 ] 
> 
> If you have 120 feet for a three element array, the YCCC array is a great 
> choice 
> It can use high impedance or low impedance verticals 
> Unfortunately its no longer available from DX Engineering 
> The nine element YCCC array uses only three active elements at any time, 
> so its really a three element array switchable in many directions. 
> 
> [ 
> https://static.dxengineering.com/global/images/instructions/dxe-yccc-switch.pdf?_gl=1*1cv0fc9*_ga*MjEyMDA1Nzc3MS4xNjUyMzAyMjc0*_ga_NZB590FMHY*MTY4MDE5NTk1OC40My4xLjE2ODAxOTYwNTYuNTAuMC4w
>  | 
> https://static.dxengineering.com/global/images/instructions/dxe-yccc-switch.pdf?_gl=1*1cv0fc9*_ga*MjEyMDA1Nzc3MS4xNjUyMzAyMjc0*_ga_NZB590FMHY*MTY4MDE5NTk1OC40My4xLjE2ODAxOTYwNTYuNTAuMC4w
>  ] 
> 
> [ https://www.youtube.com/watch?v=dl-crM5Kb6A | 
> https://www.youtube.com/watch?v=dl-crM5Kb6A ] 
> 
> [ https://www.youtube.com/watch?v=lVW1CmrzP7c | 
> https://www.youtube.com/watch?v=lVW1CmrzP7c ] 
> 
> A two element array occupies only 60 feet or even a little less. 
> 
> 73 
> Frank 
> W3LPL 
> 
> 
> ----- Original Message ----- 
> From: "Pete N4ZR N4ZR" < [ mailto:pete.n4zr@gmail.com | pete.n4zr@gmail.com ] 
> > 
> To: "topband" < [ mailto:Topband@contesting.com | Topband@contesting.com ] > 
> Sent: Thursday, March 30, 2023 12:54:30 PM 
> Subject: Topband: 2-element receiving arrays 
> 
> Thinking ahead to next winter on 160, I'm interested in replacing my 
> K9AY Loop with a 2-vertical phased array. I'd like to homebrew the 
> antennas and just buy or build the remote control unit for the shack. 
> I'm looking for sources of components (antenna-located preamps and an 
> in-shack controller), and would prefer not to completely homebrew them, 
> but the prices at the usual suspects are awfully high. Any ideas? 
> 
> I have pretty reasonably-priced access to 25 and 31-foot fiberglass 
> poles (used for wind-socks by model airplane enthusiasts). I'm thinking 
> that one relatively low-cost approach might be to attach, say, #14 wire 
> to the poles, with preamps at the base, but wonder if there is a 
> downside to using such small-diameter antenna elements rather than 1 or 
> 1.5 inch tubing? Alternatively, are clones of the DX Engineering 8' 
> short verticals with preamps a good alternative? 
> 
> -- 
> 73, Pete N4ZR 
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