My suggestion is to measure your dummy load out of the circuit. I have had this
problem with RF filter networks where the reject load (aka dummy load) is bad &
the only indicator is bad VSWR with unusual operation. It typically is not
assumed to be a problem. Most of the time the load will eat up power imbalances
but when the load is bad, it will reflect the power back into the system
causing bad VSWR in that mode. The other modes may not show much VSWR because
there just isn’t much imbalance.
Greg Best
Sent from my iPhone
> On Jan 6, 2019, at 11:00 AM, towertalk-request@contesting.com wrote:
>
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> Today's Topics:
>
> 1. Kindorf and Unistrut (Jim Thomson)
> 2. Force 12 C-31XR Manual Needed- Round 2 (Tom Hellem)
> 3. US tower remote raising switch (VE6WZ_Steve)
> 4. Re: High SWR on DXE 4sq in OMNI mode (Jorge CX6VM)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sat, 5 Jan 2019 10:51:50 -0800
> From: "Jim Thomson" <jim.thom@telus.net>
> To: <towertalk@contesting.com>
> Subject: [TowerTalk] Kindorf and Unistrut
> Message-ID: <58C9A71B27394065BCE0497AABDDB6F6@DESKTOPSV54DBH>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Date: Fri, 4 Jan 2019 12:26:27 -0600
> From: Jim <jimw7ry@gmail.com>
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] Kindorf and Unistrut
>
> <Agreed!
> <And Kindorf and Unistrut also comes in Stainless... Get out your $$ though.
>
>
> <Thanks
> <73
> <Jim W7RY
>
> ## at the telco I worked at for 34 years, unistrut was eventually used all
> over the offices,
> + cell sites etc. Also used to support the 24 x 190 kg batteries. They are
> stacked 12 above 12.
> Several strings are used on the larger offices. It makes for a fast
> install... then the entire mess is hilti
> anchored to the concrete floor, so it all ends up earth quake proof.
> Also used for a variety of applications, including supporting real heavy
> halon bottles. I even know
> one fellow, who built a spiral staircase out of it !
>
> ## I used unistrut, as a simple way of re-enforcing the 253 lb dahl xfmr on
> one of my
> 19 inch wide x 29 inch deep rack cabs. One long piece of unistrut, running
> the entire
> length, beneath the cab sheet metal, bolted at each extreme end. And 2 x
> short pieces,
> each aprx 8+ inches long, running the width of the 19 inch cab... dead
> center, below the xfmr.
> The trick is however, the short pieces can only be bolted at the outboard cab
> sides. The inboard
> side of each short piece of unistrut cant be bolted, since the xfmr is right
> above the mess. The fix
> is to use the optional unistrut option of a T shaped plate, that uses the
> handy dandy spring loaded
> nuts! That thick steel plate bonds the 3 pieces of unistrut, does not
> budge. On the top side, I installed
> a huge sheet of .25 thick Al plate, to add more strength,and to also make
> for grounding points. That same
> optional steel plate can also be used to bond 4 x pieces of unistrut
> together.
>
> Unistrut makes all sorts of optional pieces for a variety of applications.
> The spring loaded nuts also come
> in several different thread sizes. We used thousands of feet of it in just
> one telco office alone. Its a cheap
> way to get around problems, without having to resort to custom fabricated
> steel, welding etc.
>
> Jim VE7RF
>
>
>
> ------------------------------
>
> Message: 2
> Date: Sat, 5 Jan 2019 17:54:50 -0700
> From: Tom Hellem <tom.hellem@gmail.com>
> To: towertalk@contesting.com
> Subject: [TowerTalk] Force 12 C-31XR Manual Needed- Round 2
> Message-ID:
> <CANyX0ArNO5k4cJCORwc6jFhTppxXYxuu3POV1mGCbTmAHAx5-w@mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> Hi All-
> I posted a request a few days back for a copy of the manual for a Force 12
> C-31XR yagi.
> Several very generous list members responded and sent me an electronic copy.
> As it turns out I have the separate feedlines version of the antenna and
> the manuals I received are all for the jacketed feed version.
>
> Does anyone have a manual for the separate feedlines version?
> All I really need is the page showing element placement and tubing lengths,
> and the one or two pages with the information about the hairpin coils for
> the 20 and 15 meter elements. If all you have is a printed manual, a
> scanned copy of these few pages would satisfy my needs.
>
> Thanks again to all for the help.
>
> 73
> Tom
> K0SN
>
>
> ------------------------------
>
> Message: 3
> Date: Sat, 5 Jan 2019 19:04:18 -0700
> From: VE6WZ_Steve <ve6wz@shaw.ca>
> To: towertalk@contesting.com
> Subject: [TowerTalk] US tower remote raising switch
> Message-ID: <19675CFE-9E17-4EBD-996B-5F31CD5CD769@shaw.ca>
> Content-Type: text/plain; charset=utf-8
>
> I have been archiving my station notes together into an electronic file so I
> can easily retrieve them when needed.
> While uploading the files today I recalled a question here on tower talk
> about adding a remote UP-Down switch functionality to a US Tower, so I
> thought I would share this.
>
> Here is a link to my documentation for a relay board I built which emulates
> the 3PDT UP/DOWN switch which is used on the US tower HDX-589mpl Tower.
> (A lot more ?cost effective? than the US tower remote control box)
>
> https://drive.google.com/file/d/1IuR1zBhKxquJhoyo6u2hkpHEf0PWsoqe/view?usp=sharing
>
> <https://drive.google.com/file/d/1IuR1zBhKxquJhoyo6u2hkpHEf0PWsoqe/view?usp=sharing>
>
> A +12v or -12V signal will drive the tower up or down while no voltage stops
> the tower. Two 4PDT (LY4-DC-12) relays are mounted on an etched board and
> mounted inside the existing tower switch box. Terminal blocks mounted on the
> board allow for a direct install using the same terminal lugs which attach to
> the existing switch screw terminals. A schematic of the US tower switch box
> is included to identify the lug numbers, and a few photos of the installation.
>
> This relay board has been in service for three years at the VE6WZ remote
> station and is configured to be remotely controlled either manually as
> required, or via a windspeed alarm which will automatically drive the tower
> down above a set windspeed.
>
> 73, de steve ve6wz.
>
> ------------------------------
>
> Message: 4
> Date: Sun, 6 Jan 2019 13:34:49 -0300
> From: Jorge CX6VM <cx6vm.jorge@gmail.com>
> To: Jeff Blaine <KeepWalking188@ac0c.com>
> Cc: towertalk@contesting.com
> Subject: Re: [TowerTalk] High SWR on DXE 4sq in OMNI mode
> Message-ID: <F61AAC45-4E46-4488-A00A-94B644CDAF4A@gmail.com>
> Content-Type: text/plain; charset=utf-8
>
> Hi Jeff
>
> I had the same issue.
>
> Individual antennas have 1.1:1 to 1.3:1 but when in OMNI rise up to 2:1
>
> So Never used OMNI
>
> 73,
> Jorge
> CX6VM/CW5W
>
> Enviado desde mi iPad
>
> El 5 ene. 2019, a la(s) 00:59, Jeff Blaine <KeepWalking188@ac0c.com> escribi?:
>
>> My 40m 4sq works just fine in the 4 normal directions. But when I put it
>> into the OMNI mode, the swr jumps up to about 1.7:1. wondered if anyone had
>> seen this sort of issue and knew what the usual suspect is?
>>
>> Over frequency both Xj and R move a lot compared with the normal 4
>> directions. Makes me wonder if I have not blasted something or broke
>> something.
>>
>> 73/jeff/ac0c
>> alpha-charlie-zero-charlie
>> www.ac0c.com
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
> ------------------------------
>
> Subject: Digest Footer
>
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> ------------------------------
>
> End of TowerTalk Digest, Vol 193, Issue 6
> *****************************************
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