[TowerTalk] TowerTalk Digest, Vol 196, Issue 26
Greg Best
gregbestconsultant at yahoo.com
Thu Apr 25 01:37:24 EDT 2019
Thanks to you all for your questions, thoughts, and input. My original question was about interaction with the tower and really asking the question as to whether someone besides me has addressed the issue before. (Better to take advantage of work done before rather than recreate the wheel.). For your further consideration, the tower face at 60 ft is about 30” and it is 3 sided. The mount would likely be fixed on EU or a small robust sidearm with “rotator on a post” realizing that I would not be able to turn it fully around. All of the bracing is “X”
braces using 1.5” angle steel above and below the 60 ft level. The spacing between the DE & D1 is 106” so i do have some room. The balance point is abt 63” from the DE. The 20 m beam is a Wilson 204CD. I am not familiar with the NEC command to “mirror “ the wires. Is it “copy” or something else?
Tks. Greg N9GB
Greg Best
Sent from my iPhone
> On Apr 24, 2019, at 11:00 AM, towertalk-request at contesting.com wrote:
>
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> Today's Topics:
>
> 1. MODEL FOR TOWER (Jim Thomson)
> 2. Re: MODEL FOR TOWER (jimlux)
> 3. Re: MODEL FOR TOWER (Jim Brown)
> 4. Re: MODEL FOR TOWER (Dan Maguire)
> 5. Re: MODEL FOR TOWER (jimlux)
> 6. Re: MODEL FOR TOWER (john at kk9a.com)
> 7. Re: MODEL FOR TOWER (jimlux)
> 8. Re: MODEL FOR TOWER (jimlux)
> 9. Re: Liquid Electrical Tape? (Jon Pearl - W4ABC)
> 10. Re: Liquid Electrical Tape? (Patrick Greenlee)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Tue, 23 Apr 2019 09:14:43 -0700
> From: "Jim Thomson" <jim.thom at telus.net>
> To: <towertalk at contesting.com>
> Subject: [TowerTalk] MODEL FOR TOWER
> Message-ID: <D7752CF0D3054A09B820BDC0251943F2 at DESKTOPSV54DBH>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Date: Mon, 22 Apr 2019 22:53:26 -0500
> From: Greg Best <gregbestconsultant at yahoo.com>
> To: towertalk at contesting.com
> Subject: [TowerTalk] MODEL FOR TOWER
>
> <I have an 80 ft Rohn windmill tower that is equivalent or stronger than the same height SSV. The base dimension is 7? 7? and the tower tapers to 24 ? at the top . I am wondering if anyone has a NEC model for this tower (or a very similar one)? I have a 20 m 4 <el yagi I am considering installing at abt 60 ft and I am concerned about the tower impact on the pattern. The yagi at 60 ft would be in a stack with another yagi at 95 ft that is mounted on a mast.
>
> <Greg Best
>
> ## what are the tower dimensions at the 60 ft level ? Are you planning on rotating the 20m yagi at 60 ft ? If so, how do you intend to rotate it ? IF the tower is say 3 ft on a side at the 60 ft level, depending
> on how the yagi is mounted, could possibly create issues. However, being a 4 el yagi, you should have plenty of space between DE and 1st DIR...so it might be a moot point. Back in the early 80s, I side mounted a
> hb 20m yagi, on a 30 ft boom, with equal spaced eles.... onto the side of a triangular L+R tower, which had a face width of aprx 34 inches. Those sections were straight, not tapered, and sections were 20 ft long.
> Zero issues on 20m. No interaction between tower and yagi, but I had 10 ft of space to play with, in the middle of the boom. Might be different story if a say 204BA was used, with its 26 ft boom.
>
> Jim VE7RF
>
>
>
> ------------------------------
>
> Message: 2
> Date: Tue, 23 Apr 2019 11:11:01 -0700
> From: jimlux <jimlux at earthlink.net>
> To: towertalk at contesting.com
> Subject: Re: [TowerTalk] MODEL FOR TOWER
> Message-ID: <7666c398-6e65-3e6c-572d-d7036fc81091 at earthlink.net>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
>> On 4/22/19 8:53 PM, Greg Best via TowerTalk wrote:
>> I have an 80 ft Rohn windmill tower that is equivalent or stronger than the same height SSV. The base dimension is 7? 7? and the tower tapers to 24 ? at the top . I am wondering if anyone has a NEC model for this tower (or a very similar one)? I have a 20 m 4 el yagi I am considering installing at abt 60 ft and I am concerned about the tower impact on the pattern. The yagi at 60 ft would be in a stack with another yagi at 95 ft that is mounted on a mast.
>>
>>
>
> This is one of those things that might be easiest to generate with a
> short program in the language of your choice to generate the lattice of
> vertical, horizontal, and diagonal members. I've done that to generate
> a model for a truss - it was easier to do that than to try and figure
> out the coordinates by hand.
>
> There *might* be a cad program in which you could quickly draw the
> tower, and export the segment endpoints.
>
> Because it's tapered, it doesn't lend itself to using a GM card to
> replicate segments.
>
> You'd model it as a wire for each structural member, and pick the
> diameter of the wire to have the same circumference as the perimeter of
> the structural member (or, heck, just make em all 2" diameter wires).
>
>
> for each section do:
> calculate the coordinates of the 8 corners
> (or 6 corners if it's three sided)
> generate a wire for the 4 verticals corners
> generate wires for each of the horizontals
> generate wires for the diagonal braces
>
>
>
>
>
>
>
> ------------------------------
>
> Message: 3
> Date: Tue, 23 Apr 2019 13:05:41 -0700
> From: Jim Brown <jim at audiosystemsgroup.com>
> To: towertalk at contesting.com
> Subject: Re: [TowerTalk] MODEL FOR TOWER
> Message-ID:
> <dc7a8f94-ab93-bd88-53f7-a9556b29dd6e at audiosystemsgroup.com>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
> There is also at least one equation I found on the web that computes the
> effective diameter of a triangular tower based on it's cross-section. It
> might be possible to get a reasonable approximation of the tower by
> breaking the tower down into multiple sections.
>
> The equation I found is tricky to express via email.? The equivalent
> diameter is the cube root of (D x Fsquared /2), where D is the diameter
> of a leg and F is the face width.
>
> There may be a comparable equation for a tower with a square cross section.
>
> Elaborating on Jim's method, EZNEC has a command that allows wires to be
> duplicated rotated about some center point. That would allow one of the
> vertical members to be modeled, then duplicated in 90 or 120 degree
> increments. Cross-members could then be added between the intersections
> of the "wires."
>
> In my professional life, I generated models of large and small
> performance spaces to aid in the design sound systems by studying their
> coverage of the audience and their interaction with the acoustic
> environment. The largest and most complex space I "built" was the Staple
> Center in Los Angeles. Those models use the same x, y, z coordinate
> system, and the surfaces are all planes with their acoustic
> characteristics defined. In building those models, I made a table of x,
> y, and z coordinates of the points defining the surfaces before trying
> to build the model.? A similar approach would be applicable here.
>
> 73, Jim K9YC
>
>> On 4/23/2019 11:11 AM, jimlux wrote:
>>> On 4/22/19 8:53 PM, Greg Best via TowerTalk wrote:
>>> I have an 80 ft Rohn windmill tower that is equivalent or stronger
>>> than the same height SSV. The base dimension is 7? 7? and the tower
>>> tapers to 24 ? at the top . I am wondering if anyone has a NEC model
>>> for this tower (or a very similar one)?? I have a 20 m 4 el yagi I am
>>> considering installing at abt 60 ft and I am concerned about the
>>> tower impact on the pattern. The yagi at 60 ft would be in a stack
>>> with another yagi at 95 ft that is mounted on a mast.
>>>
>>>
>>
>> This is one of those things that might be easiest to generate with a
>> short program in the language of your choice to generate the lattice
>> of vertical, horizontal, and diagonal members.?? I've done that to
>> generate a model for a truss - it was easier to do that than to try
>> and figure out the coordinates by hand.
>>
>> There *might* be a cad program in which you could quickly draw the
>> tower, and export the segment endpoints.
>>
>> Because it's tapered, it doesn't lend itself to using a GM card to
>> replicate segments.
>>
>> You'd model it as a wire for each structural member, and pick the
>> diameter of the wire to have the same circumference as the perimeter
>> of the structural member (or, heck, just make em all 2" diameter wires).
>>
>>
>> for each section do:
>> ????calculate the coordinates of the 8 corners
>> ??????? (or 6 corners if it's three sided)
>> ????generate a wire for the 4 verticals corners
>> ????generate wires for each of the horizontals
>> ????generate wires for the diagonal braces
>>
>>
>>
>>
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk at contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
>
> ------------------------------
>
> Message: 4
> Date: Tue, 23 Apr 2019 15:37:34 -0700
> From: Dan Maguire <danac6la at gmail.com>
> To: towertalk <towertalk at contesting.com>
> Subject: Re: [TowerTalk] MODEL FOR TOWER
> Message-ID:
> <CAOnXRMvwsHcMNJ7ikG5-mCCuHf9E33zz+_cfFoUr2jVgvn+Zew at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> K9YC wrote:
>>>> There is also at least one equation I found on the web that computes the effective diameter of a triangular tower based on it's cross-section.
>
> Perhaps here:
> https://en.wikipedia.org/wiki/Antenna_equivalent_radius
>
> As a comparison, the lower-right of this image shows both the Leeson
> and Wikipedia equivalent diameter for a Rohn 25G cross section:
> https://ac6la.com/adhoc/4sq1a.png
>
> AutoEZ users, the Leeson and Wikipedia formulas are on the Variables
> sheet tab for the "Bent Dipole 4-sq" *.weq model files as described in
> the first section here:
> https://ac6la.com/aecollection8.html
>
> Dan, AC6LA
>
>
> ------------------------------
>
> Message: 5
> Date: Tue, 23 Apr 2019 18:18:20 -0700
> From: jimlux <jimlux at earthlink.net>
> To: towertalk at contesting.com
> Subject: Re: [TowerTalk] MODEL FOR TOWER
> Message-ID: <ac822191-388e-cb3a-ecd8-a664bca5f1f4 at earthlink.net>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
>> On 4/23/19 1:05 PM, Jim Brown wrote:
>> There is also at least one equation I found on the web that computes the
>> effective diameter of a triangular tower based on it's cross-section. It
>> might be possible to get a reasonable approximation of the tower by
>> breaking the tower down into multiple sections.
>>
>> The equation I found is tricky to express via email.? The equivalent
>> diameter is the cube root of (D x Fsquared /2), where D is the diameter
>> of a leg and F is the face width.
>
> This doesn't do the horizontal crossing pieces (which are actually the
> most likely to cause problems - they're long, and they're aligned with
> the antenna elements) and the diagonal struts.
>
>
>>
>> There may be a comparable equation for a tower with a square cross section.
>>
>> Elaborating on Jim's method, EZNEC has a command that allows wires to be
>> duplicated rotated about some center point. That would allow one of the
>> vertical members to be modeled, then duplicated in 90 or 120 degree
>> increments. Cross-members could then be added between the intersections
>> of the "wires."
>
> NEC has the GM card which can create copies rotated around a center,
> and that will do the wires. And it can do the horizontal members, too:
> you build one "corner" of the structure, and tell NEC to rotate it 90
> degrees and create 3 copies.
> The diagonal struts, though, are the challenge.
>
> When I've done this kind of thing, I've always just wound up writing a
> short program in whatever language (basic, matlab, python) that just
> cranks out GW cards for all the required members.
>
> A program like 4nec2 can help visualize the model once you've built it.
>
> You could, if you're ambitious, actually write a program in the symbol
> handling language of 4nec2 to allow you to specify height and size at
> top and bottom, and do all the algebra to get the endpoints...
> But it's a pain doing that.
> By the time you've done that, it's just as easy to write a program in
> something else, and a LOT easier to debug it.
>
> you wind up having a lot of statements that look like this
> f.write("GW %d %d %f %f %f %f %f %f
> %f\n"%(wirenum,nsegs,x1,y1,z1,x2,y2,z2,radius))
>
> (I was actually writing python code this afternoon that does just this
> and that's the actual line out of the code)
>
> If your structure DOES have symmetry, then building part and using GM to
> replicate it does model a bit faster.
>
> I find that computers run so fast now, it's not always worth doing, but
> if you're getting up to 1000s of segments, maybe it's worth while.
>
>
>
>
>>
>> In my professional life, I generated models of large and small
>> performance spaces to aid in the design sound systems by studying their
>> coverage of the audience and their interaction with the acoustic
>> environment. The largest and most complex space I "built" was the Staple
>> Center in Los Angeles. Those models use the same x, y, z coordinate
>> system, and the surfaces are all planes with their acoustic
>> characteristics defined. In building those models, I made a table of x,
>> y, and z coordinates of the points defining the surfaces before trying
>> to build the model.? A similar approach would be applicable here.
>
>
> Yeah, the same basic strategy for NEC.
>
> The holy grail of EM modeling is something that will take a mechanical
> cad drawing and "grid it" - whether into wires for a Method of Moments
> code like NEC or into triangles for modeling tools that want patches.
>
>
>
>>
>> 73, Jim K9YC
>>
>>> On 4/23/2019 11:11 AM, jimlux wrote:
>>>> On 4/22/19 8:53 PM, Greg Best via TowerTalk wrote:
>>>> I have an 80 ft Rohn windmill tower that is equivalent or stronger
>>>> than the same height SSV. The base dimension is 7? 7? and the tower
>>>> tapers to 24 ? at the top . I am wondering if anyone has a NEC model
>>>> for this tower (or a very similar one)?? I have a 20 m 4 el yagi I am
>>>> considering installing at abt 60 ft and I am concerned about the
>>>> tower impact on the pattern. The yagi at 60 ft would be in a stack
>>>> with another yagi at 95 ft that is mounted on a mast.
>>>>
>>>>
>>>
>>> This is one of those things that might be easiest to generate with a
>>> short program in the language of your choice to generate the lattice
>>> of vertical, horizontal, and diagonal members.?? I've done that to
>>> generate a model for a truss - it was easier to do that than to try
>>> and figure out the coordinates by hand.
>>>
>>> There *might* be a cad program in which you could quickly draw the
>>> tower, and export the segment endpoints.
>>>
>>> Because it's tapered, it doesn't lend itself to using a GM card to
>>> replicate segments.
>>>
>>> You'd model it as a wire for each structural member, and pick the
>>> diameter of the wire to have the same circumference as the perimeter
>>> of the structural member (or, heck, just make em all 2" diameter wires).
>>>
>>>
>>> for each section do:
>>> ????calculate the coordinates of the 8 corners
>>> ??????? (or 6 corners if it's three sided)
>>> ????generate a wire for the 4 verticals corners
>>> ????generate wires for each of the horizontals
>>> ????generate wires for the diagonal braces
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
>>> TowerTalk mailing list
>>> TowerTalk at contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk at contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
> ------------------------------
>
> Message: 6
> Date: Wed, 24 Apr 2019 06:42:53 -0500
> From: john at kk9a.com
> To: towertalk at contesting.com
> Subject: Re: [TowerTalk] MODEL FOR TOWER
> Message-ID:
> <20190424064253.Horde.Bs_ugVk4kYK-QbIiDv8OFVS at www11.qth.com>
> Content-Type: text/plain; charset=utf-8; format=flowed; DelSp=Yes
>
> Great information Dan!
>
> I have always just guess when converting a tower to a wire diameter.
> The original poster seemed concerned that his tower would effect his
> horizontally polarized HF beams, I have not seen that occur.
>
> John KK9A
>
>
>
> Dan Maguire AC6LA wrote:
>
>
> Perhaps here:
> https://en.wikipedia.org/wiki/Antenna_equivalent_radius
>
> As a comparison, the lower-right of this image shows both the Leeson
> and Wikipedia equivalent diameter for a Rohn 25G cross section:
> https://ac6la.com/adhoc/4sq1a.png
>
> AutoEZ users, the Leeson and Wikipedia formulas are on the Variables
> sheet tab for the "Bent Dipole 4-sq" *.weq model files as described in
> the first section here:
> https://ac6la.com/aecollection8.html
>
> Dan, AC6LA
>
>
>
> ------------------------------
>
> Message: 7
> Date: Wed, 24 Apr 2019 05:40:59 -0700
> From: jimlux <jimlux at earthlink.net>
> To: towertalk at contesting.com
> Subject: Re: [TowerTalk] MODEL FOR TOWER
> Message-ID: <41d5a867-c5a5-249c-412c-41c9346ffbec at earthlink.net>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
>> On 4/24/19 4:42 AM, john at kk9a.com wrote:
>> Great information Dan!
>>
>> I have always just guess when converting a tower to a wire diameter. The
>> original poster seemed concerned that his tower would effect his
>> horizontally polarized HF beams, I have not seen that occur.
>>
>> John KK9A
>
> I think the question would be about the SSV/BX style tower which is
> larger at the bottom than the top. Rohn 25 or 45 are "small" compared to
> a wavelength in the horizontal direction, so they can be modeled as a
> "fat wire" - just like a cage dipole element, for instance.
>
> The tower in question is 7.5 ft at the bottom and 2 ft at the top 80 ft
> high.
> The OP was asking about a 20m Yagi to be mounted at 60 ft, where you'd
> effectively have big square loops that are about 3 1/2 ft on a side (14
> ft total perimeter) near the antenna, as well as diagonal struts of
> some length.
>
> The wavelength is 60-70 ft, so those squares are about 1/4 wavelength in
> perimeter. If they were 1/10th wavelength, I'd say "model it as a big
> wire", but that's big enough that there might be some interaction,
> especially since they will be effectively "inside" the Yagi.
>
>
>
>
>
>
>>
>>
>>
>> Dan Maguire AC6LA wrote:
>>
>>
>> Perhaps here:
>> https://en.wikipedia.org/wiki/Antenna_equivalent_radius
>>
>> As a comparison, the lower-right of this image shows both the Leeson
>> and Wikipedia equivalent diameter for a Rohn 25G cross section:
>> https://ac6la.com/adhoc/4sq1a.png
>>
>> AutoEZ users, the Leeson and Wikipedia formulas are on the Variables
>> sheet tab for the "Bent Dipole 4-sq" *.weq model files as described in
>> the first section here:
>> https://ac6la.com/aecollection8.html
>>
>> Dan, AC6LA
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk at contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
> ------------------------------
>
> Message: 8
> Date: Wed, 24 Apr 2019 05:50:58 -0700
> From: jimlux <jimlux at earthlink.net>
> To: towertalk at contesting.com
> Subject: Re: [TowerTalk] MODEL FOR TOWER
> Message-ID: <1c78c460-b5e6-9268-487a-3ca76522165f at earthlink.net>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
>> On 4/22/19 8:53 PM, Greg Best via TowerTalk wrote:
>> I have an 80 ft Rohn windmill tower that is equivalent or stronger than the same height SSV. The base dimension is 7? 7? and the tower tapers to 24 ? at the top . I am wondering if anyone has a NEC model for this tower (or a very similar one)? I have a 20 m 4 el yagi I am considering installing at abt 60 ft and I am concerned about the tower impact on the pattern. The yagi at 60 ft would be in a stack with another yagi at 95 ft that is mounted on a mast.
>>
>> Greg Best
>>
>
>
> So, is that like a SSV 5N, 6N, 7N,8N stack - the dimensions are a bit
> different...
>
> It's bigger than a RSL series.
>
> Triangular cross section?
> All diagonal braces or does it have horizontal struts too?
>
>
> ------------------------------
>
> Message: 9
> Date: Wed, 24 Apr 2019 09:14:10 -0400
> From: Jon Pearl - W4ABC <jonpearl at tampabay.rr.com>
> To: Keith Dutson <kdutson at sbcglobal.net>, 'towertalk reflector'
> <towertalk at contesting.com>
> Subject: Re: [TowerTalk] Liquid Electrical Tape?
> Message-ID: <8425deae-1c6e-6d01-2823-c305d4e6a2e0 at tampabay.rr.com>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
> Hi Keith,
>
> I've used 2228 all by its lonesome and it's pretty impressive. Tape,
> 2228, then tape again might be the ticket for an even longer, long term
> solution:
>
> http://www.w4abc.com/Scotch2228.html
>
>
>
>
> 73,
>
>
> Jon Pearl - W4ABC
>
>
>> On 4/2/2019 9:46 PM, Keith Dutson wrote:
>> I have heard the best is 3M Scotchkote. However, I recently inspected a
>> coax connection on the outdoor 2 meter cable running from repeater to
>> antenna (on top of 500 foot building). It had been slathered with
>> Scotchkote after sealing with two wraps of 88, one wrap of 2228 fusion tape
>> and two final wraps of 88. It appears the Scotchkote was useless in the
>> harsh outdoor environment at 500 feet. It was dry and balled up, exposing
>> the 88 underneath. This connection was inspected because of high SWR at the
>> duplexer bottles. The problem was discovered to be the N barrel connecting
>> two runs of LDF50A. The first wrap of 88 with sticky side out made the
>> removal a snap.
>>
>> 73 Keith NM5G
>>
>>
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
>
>
>
> ------------------------------
>
> Message: 10
> Date: Wed, 24 Apr 2019 08:40:15 -0500
> From: Patrick Greenlee <patrick_g at windstream.net>
> To: towertalk at contesting.com
> Subject: Re: [TowerTalk] Liquid Electrical Tape?
> Message-ID: <261f4dc9-0d8e-9b25-0fca-481cca4733bb at windstream.net>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
> In the olden days I used to use Glyptal (a high voltage resistant
> lacquer) to seal the edges of multi-layered glass covered narrow band UV
> filters.? The filters came in 4x4 inch standard size.? I had them sawn
> into 3/4 by 3/4 inch pieces and then had to seal the edges against
> moisture intrusion as the filters were used in medical equipment used in
> a moist environment.? I never had a failure relating to the use of the
> Glyptal as a moisture barrier.
>
> I would think that Glyptal would do a good job in sealing things against
> moisture intrusion provided the area treated with it did not flex so
> much as to significantly stress the flexibility of the Glyptal.
>
> Anyone out there have personal experience with Glyptal as a water tight
> sealant?
>
> Patrick??????? NJ5G
>
>> On 4/24/2019 8:14 AM, Jon Pearl - W4ABC wrote:
>> Hi Keith,
>>
>> I've used 2228 all by its lonesome and it's pretty impressive. Tape,
>> 2228, then tape again might be the ticket for an even longer, long
>> term solution:
>>
>> http://www.w4abc.com/Scotch2228.html
>>
>>
>>
>>
>> 73,
>>
>>
>> Jon Pearl - W4ABC
>>
>>
>>> On 4/2/2019 9:46 PM, Keith Dutson wrote:
>>> I have heard the best is 3M Scotchkote. However, I recently inspected a
>>> coax connection on the outdoor 2 meter cable running from repeater to
>>> antenna (on top of 500 foot building).? It had been slathered with
>>> Scotchkote after sealing with two wraps of 88, one wrap of 2228
>>> fusion tape
>>> and two final wraps of 88.? It appears the Scotchkote was useless in the
>>> harsh outdoor environment at 500 feet.? It was dry and balled up,
>>> exposing
>>> the 88 underneath.? This connection was inspected because of high SWR
>>> at the
>>> duplexer bottles.? The problem was discovered to be the N barrel
>>> connecting
>>> two runs of LDF50A.? The first wrap of 88 with sticky side out made the
>>> removal a snap.
>>>
>>> 73 Keith NM5G
>>>
>>>
>>
>> ---
>> This email has been checked for viruses by Avast antivirus software.
>> https://www.avast.com/antivirus
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk at contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
>
>
> ------------------------------
>
> Subject: Digest Footer
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
> ------------------------------
>
> End of TowerTalk Digest, Vol 196, Issue 26
> ******************************************
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