[Towertalk] Re: Towertalk digest, Vol 1 #24 - 12 msgs
Warren Munro
wmunro@lava.net
Tue, 12 Mar 2002 08:25:33 -1000
on 3/11/02 7:47 PM, towertalk-request@contesting.com at
towertalk-request@contesting.com wrote:
> Send Towertalk mailing list submissions to
> towertalk@contesting.com
>
> To subscribe or unsubscribe via the World Wide Web, visit
> http://lists.contesting.com/mailman/listinfo/towertalk
> or, via email, send a message with subject or body 'help' to
> towertalk-request@contesting.com
>
> You can reach the person managing the list at
> towertalk-admin@contesting.com
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Towertalk digest..."
>
>
> Today's Topics:
>
> 1. Re: Template for CDE Rotator Needed (n0tt1@juno.com)
> 2. Reflection Gain (jljarvis)
> 3. RE: Cushcraft R7000 and Salt Water Locations (W4ZW)
> 4. Re: Reflection Gain (K3BU@aol.com)
> 5. Re: Reflection Gain (Chris Adams)
> 6. Thanks for CDE Rotor Template Info! (Eric Rosenberg)
> 7. Re: Reflection Gain (Guy Olinger, K2AV)
> 8. Re: Reflection Gain (Guy Olinger, K2AV)
> 9. Fwd: Re: [Towertalk] Template for CDE Rotator Needed (Jim Rhodes)
> 10. reflection gain addendum (Chris Adams)
> 11. Re: Grounding an Elevated vertical (Guy Olinger, K2AV)
> 12. Fw: Antenna parts search (Guy Olinger, K2AV)
>
> --__--__--
>
> Message: 1
> To: SPELUNK.SUENO@prodigy.net, Towertalk@contesting.com
> Date: Mon, 11 Mar 2002 01:31:09 +0000
> Subject: Re: [Towertalk] Template for CDE Rotator Needed
> From: n0tt1@juno.com
>
> Gene,
>
> You can make your own template...
>
> All you have to do is tape a thin piece of paper to the bottom,
> then rub the paper over the holes with the "side" of a lead pencil
> point. Your pattern will then be transferred to the paper.
>
> 73,
> Charlie, N0TT
>
>
> ________________________________________________________________
> GET INTERNET ACCESS FROM JUNO!
> Juno offers FREE or PREMIUM Internet access for less!
> Join Juno today! For your FREE software, visit:
> http://dl.www.juno.com/get/web/.
>
> --__--__--
>
> Message: 2
> From: "jljarvis" <jljarvis@abs.adelphia.net>
> To: <towertalk@contesting.com>
> Date: Mon, 11 Mar 2002 20:59:27 -0500
> Subject: [Towertalk] Reflection Gain
>
>
> With due respect, Yuri....reflection gain exists for
> grazing incidence moonbounce signals. There is an
> additive behavior here, which recovers part of the
> signal which would be below the horizon, but reflect back
> up to add into the beam. But this is NOT at HF...it's at VHF/UHF.
>
> It does NOT exist for vertically polarized HF signals over
> earth. All you're seeing over seawater is reduced attenuation
> from imperfect earth...when you get to highly conductive ocean.
>
> Yes, you're right that highly conductive ground also reduces
> IR losses at the drive point.
>
> But at low angles, you do NOT get gain from a good ground plane.
> All you get is reduced attenuation. Result is the same...the
> process is different.
>
> n2ea
>
> -0-
>
>> Any language suggesting 'seawater gain', or 'reflection gain',
>> is imprecise, at best. It IS true that verticals work better over highly
>> conductive earth. But there ain't no gain there.
>
> There IS a gain somewhere between 10 - 15 dB next to, or over salt water with
> vertical antennas as compared to similar antennas installed inland. Jump in
> the mobile and drive around you WILL see it! Even modeling programs show it.
>
> Numerous factors come into a play with salt water front: better "ground"
> improves efficiency of the antennas, huge "ground plane" brings gain at very
> low angles (Brewster), unobstructed plane horizon and no noise generators out
> there (except sun).
>
>
> Jim Jarvis
> Keithley Instruments
> Essex Vermont
> 802 872 5830 voice
> 802 872 5831 fax
>
>
>
>
> --__--__--
>
> Message: 3
> Date: Mon, 11 Mar 2002 21:24:51 -0500
> From: W4ZW <w4zw@comcast.net>
> Subject: RE: [Towertalk] Cushcraft R7000 and Salt Water Locations
> To: kk9a@arrl.net, nat@ajheatwole.com, towertalk@contesting.com
>
> I believe Yuri makes several good points about a saltwater surrounding
> in his post.
>
> I can only offer anecdotal experiences, since I live on an island with
> the ocean on one side (about 330' from the house ( NNW to S) and a
> saltwater bay about 350' on the other ( N to SSE). I often can be
> working JA's on my mobile rig in the car with perfect Q5 signals and
> they will abruptly disappear as I cross over the bridge to the mainland.
> I have intentionally made a U turn, retraced my path and as soon as I'm
> almost to the bridge, they pop back up out of the noise. I use a
> screwdriver vertical on the back of the car.
>
> I often hear and work DX, especially on the low bands, that friends just
> a few miles inland can't hear. I installed an Outbacker on my boa
> which is docked on the bay side and I am always amazed at well it
> works. Lots of comments from DX stations like "you're sure loud to be
> a mobile."
>
> I do know that my 402CD works better here than I've ever experienced
> before. I always feel loud on 40M, even running QRP. The 402CD and my
> 80M Bobtail always seem to get me through the pile-ups in only 1 or 2
> calls, often running low power on these bands since I have TVI problems.
>
> I call the ocean "nature's amp". Works for me.
>
> My purely unscientific experience FWIW.
>
>
> Jon Hamlet, W4ZW
> Casey Key Island, FL
>
> "A little bit of Paradise in the Gulf of Mexico"
>
>
>
>
> --__--__--
>
> Message: 4
> From: K3BU@aol.com
> Date: Mon, 11 Mar 2002 22:51:34 EST
> Subject: Re: [Towertalk] Reflection Gain
> To: towertalk@contesting.com
>
> In a message dated 3/11/02 9:09:35 PM Eastern Standard Time,
> jljarvis@abs.adelphia.net writes:
>
>>
>> But at low angles, you do NOT get gain from a good ground plane.
>> All you get is reduced attenuation. Result is the same...the
>> process is different.
>
> So what you call it when I see increase in signal level when driving close to
> the ocean (good ground plane)? Negative attenuation? :-)
> What do you call increase in signals near ocean by 10 - 15 db? (same antenna,
> same car) Reduced attenuation?
>
> When you look at the patterns of verticals over lousy ground and ocean or
> perfect ground, you see pattern being filled down to horizon. If one antenna
> has more signal at particular angle than another, that is usually called gain.
>
> So what about them verticals over sloping terrain? Does anybody have any
> experiences with that situation?
>
> Yuri, K3BU/mmmmm
>
> --__--__--
>
> Message: 5
> Date: Mon, 11 Mar 2002 21:11:22 -0700
> From: "Chris Adams" <n4vi@arrl.net>
> To: towertalk@contesting.com
> Organization: http://www.qsl.net/n4vi
> Subject: Re: [Towertalk] Reflection Gain
>
> Jim,
>
> I respectfully disagree with you.
>
> If the statement that reduced attenuation is caused by Seawater and not by
> signal
> reflection from the ground, then take the process to the ideal limits, free
> space
> and a perfectly conducting ground. The signal from the perfectly conducting
> ground case is substantially higher (5.15dbi vs. 1.77 dbi according to EZNEC).
> The way this happens is energy that is destined for "below ground" in the free
> space case is reflecting by the perfectly conducting ground and stays "above
> ground".
>
>
> Secondly, the ARRL antenna book has slightly over 2 1/2 pages related to the
> Vertical reflection coefficient. There is no mention of it being valid for
> only
> VHF/UHF frequencies and there is a graph of Pseudo-Brewster angle vs. various
> types of ground for frequencies varying from 1.8 to 30 MHz. (18th edition ARRL
> antenna book, pages 3-5 to 3-8).
>
> Another "ham"related reference is "Horizontal Antennas and the Compound
> Reflection Coefficient" in the ARRL Antenna compendium Vol 3. Although this
> article is primarily about the Horizontal Reflection coefficent, there are a
> few
> paragraphs devoted to the vertical reflection coefficient.
>
>
> chris adams/ n4vi
>
>
> jljarvis wrote:
>
>> With due respect, Yuri....reflection gain exists for
>> grazing incidence moonbounce signals. There is an
>> additive behavior here, which recovers part of the
>> signal which would be below the horizon, but reflect back
>> up to add into the beam. But this is NOT at HF...it's at VHF/UHF.
>>
>> It does NOT exist for vertically polarized HF signals over
>> earth. All you're seeing over seawater is reduced attenuation
>> from imperfect earth...when you get to highly conductive ocean.
>>
>> Yes, you're right that highly conductive ground also reduces
>> IR losses at the drive point.
>>
>> But at low angles, you do NOT get gain from a good ground plane.
>> All you get is reduced attenuation. Result is the same...the
>> process is different.
>>
>> n2ea
>>
>> -0-
>>
>>> Any language suggesting 'seawater gain', or 'reflection gain',
>>> is imprecise, at best. It IS true that verticals work better over highly
>>> conductive earth. But there ain't no gain there.
>>
>> There IS a gain somewhere between 10 - 15 dB next to, or over salt water with
>> vertical antennas as compared to similar antennas installed inland. Jump in
>> the mobile and drive around you WILL see it! Even modeling programs show it.
>>
>> Numerous factors come into a play with salt water front: better "ground"
>> improves efficiency of the antennas, huge "ground plane" brings gain at very
>> low angles (Brewster), unobstructed plane horizon and no noise generators out
>> there (except sun).
>>
>> Jim Jarvis
>> Keithley Instruments
>> Essex Vermont
>> 802 872 5830 voice
>> 802 872 5831 fax
>>
>> _______________________________________________
>> Towertalk mailing list
>> Towertalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
> --__--__--
>
> Message: 6
> Date: Mon, 11 Mar 2002 23:34:42 -0500
> To: towertalk@contesting.com
> From: Eric Rosenberg <wd3q@erols.com>
> Subject: [Towertalk] Thanks for CDE Rotor Template Info!
>
> Thanks to all who replied to my question.
>
> I now have the template and some great suggestions as to why *not* to
> cut a hole in the
> old rotor plate!
>
> Thanks,
>
> Eric W3DQ
> Washington, DC
>
>
> --__--__--
>
> Message: 7
> From: "Guy Olinger, K2AV" <k2av@contesting.com>
> To: "jljarvis" <jljarvis@abs.adelphia.net>,
> "TowerTalk" <towertalk@contesting.com>
> Subject: Re: [Towertalk] Reflection Gain
> Date: Mon, 11 Mar 2002 23:32:51 -0500
>
> Let's call that spectacularly reduced attenuation at low angles.
>
> If you haven't heard it come in driving up to and onto a saltwater
> beach with a mobile HF rig/whip, you've missed one of life's great
> hamming experiences.
>
> It's like somebody turned on the switch. The difference at those 2-4
> degree incoming angles is astonishing.
>
> 73, Guy.
>
> ----- Original Message -----
> From: "jljarvis" <jljarvis@abs.adelphia.net>
> To: <towertalk@contesting.com>
> Sent: Monday, March 11, 2002 8:59 PM
> Subject: [Towertalk] Reflection Gain
>
>
>
> With due respect, Yuri....reflection gain exists for
> grazing incidence moonbounce signals. There is an
> additive behavior here, which recovers part of the
> signal which would be below the horizon, but reflect back
> up to add into the beam. But this is NOT at HF...it's at VHF/UHF.
>
> It does NOT exist for vertically polarized HF signals over
> earth. All you're seeing over seawater is reduced attenuation
> from imperfect earth...when you get to highly conductive ocean.
>
> Yes, you're right that highly conductive ground also reduces
> IR losses at the drive point.
>
> But at low angles, you do NOT get gain from a good ground plane.
> All you get is reduced attenuation. Result is the same...the
> process is different.
>
> n2ea
>
> -0-
>
>> Any language suggesting 'seawater gain', or 'reflection gain',
>> is imprecise, at best. It IS true that verticals work better over
> highly
>> conductive earth. But there ain't no gain there.
>
> There IS a gain somewhere between 10 - 15 dB next to, or over salt
> water with
> vertical antennas as compared to similar antennas installed inland.
> Jump in
> the mobile and drive around you WILL see it! Even modeling programs
> show it.
>
> Numerous factors come into a play with salt water front: better
> "ground"
> improves efficiency of the antennas, huge "ground plane" brings gain
> at very
> low angles (Brewster), unobstructed plane horizon and no noise
> generators out
> there (except sun).
>
>
> Jim Jarvis
> Keithley Instruments
> Essex Vermont
> 802 872 5830 voice
> 802 872 5831 fax
>
>
>
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
>
> --__--__--
>
> Message: 8
> From: "Guy Olinger, K2AV" <k2av@contesting.com>
> To: "jljarvis" <jljarvis@abs.adelphia.net>,
> "TowerTalk" <towertalk@contesting.com>
> Subject: Re: [Towertalk] Reflection Gain
> Date: Mon, 11 Mar 2002 23:54:33 -0500
>
> Another point. There is a bit of a double standard in being picky
> about that gain really being elimination of attenuation.
>
> Say you have a trap beam with a lossy trap that measures 3 dbd gain,
> and you replace the trap with a good one, and the gain is now 4 dbd?
> Do you call that increase in gain or elimination of loss. If it was
> elimination of loss then what was the gain of the beam with the lossy
> trap.
>
> If you say the gain was really 4 db in the prior measurement with 1 db
> of loss, then you are publishing specs like a certain antenna company,
> only they don't tell you about the loss.
>
> If you say not, then you contradict yourself.
>
> Or worse, suppose you don't KNOW the trap was lossy, and you got a NEW
> DESIGN trap to replace it. Now the gain is 4 dbd. You would call that
> gain because you THOUGHT you were replacing one design with another
> increasing the gain, only unbeknownst you were only reducing loss. And
> would remain forever deceived.
>
> Which gets us to the point of how one defines the system.
>
> In a yagi design, particularly the biggies, there is always loss
> inherent. You might lose 10% of the power in resistive loss. Do we say
> the gain of the yagi is 15 dbi with 1 db loss or do we say the gain of
> the yagi is 14 db?
>
> Of course we say 14 dbi, and we count the loss as PART OF THE SYSTEM.
>
> Do we dare say that the ground losses and unrealized potential of
> reflection reinforcement is not part of the system? Or that placing
> the antenna with saltwater in the close first bounce zone is not part
> of the system?
>
> The gain of the SYSTEM increases as we approach the salt water, even
> if you are picky about whether it is antenna gain or not.
>
> 73, Guy.
>
>
>
> ----- Original Message -----
> From: "jljarvis" <jljarvis@abs.adelphia.net>
> To: <towertalk@contesting.com>
> Sent: Monday, March 11, 2002 8:59 PM
> Subject: [Towertalk] Reflection Gain
>
>
>
> With due respect, Yuri....reflection gain exists for
> grazing incidence moonbounce signals. There is an
> additive behavior here, which recovers part of the
> signal which would be below the horizon, but reflect back
> up to add into the beam. But this is NOT at HF...it's at VHF/UHF.
>
> It does NOT exist for vertically polarized HF signals over
> earth. All you're seeing over seawater is reduced attenuation
> from imperfect earth...when you get to highly conductive ocean.
>
> Yes, you're right that highly conductive ground also reduces
> IR losses at the drive point.
>
> But at low angles, you do NOT get gain from a good ground plane.
> All you get is reduced attenuation. Result is the same...the
> process is different.
>
> n2ea
>
> -0-
>
>> Any language suggesting 'seawater gain', or 'reflection gain',
>> is imprecise, at best. It IS true that verticals work better over
> highly
>> conductive earth. But there ain't no gain there.
>
> There IS a gain somewhere between 10 - 15 dB next to, or over salt
> water with
> vertical antennas as compared to similar antennas installed inland.
> Jump in
> the mobile and drive around you WILL see it! Even modeling programs
> show it.
>
> Numerous factors come into a play with salt water front: better
> "ground"
> improves efficiency of the antennas, huge "ground plane" brings gain
> at very
> low angles (Brewster), unobstructed plane horizon and no noise
> generators out
> there (except sun).
>
>
> Jim Jarvis
> Keithley Instruments
> Essex Vermont
> 802 872 5830 voice
> 802 872 5831 fax
>
>
>
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
>
> --__--__--
>
> Message: 9
> Date: Mon, 11 Mar 2002 23:09:01 -0600
> To: TOWERTALK@contesting.com
> From: Jim Rhodes <rhodes@evertek.net>
> Subject: Fwd: Re: [Towertalk] Template for CDE Rotator Needed
>
> Well, here's my alternative. I use studs in the rotor case with a jam nut
> tightened up against the case. I don't run the cable out the side, so I
> don't need to use any extra space. But the rotator is easier to install. No
> standing on your head on the tower to see if you have the holes lined up.
> Just drop the studs through the holes in the rotator plate & put the locks
> & nuts on. I suppose I could locktight the studs in and do away with the
> jam nuts, but this has worked so well over the years that I see no need to
> change.
>
>
>> Eric:
>>
>> Yet another alternative is to use a stack of SS washers between the
>> bottom of the rotator housing and the mounting plate. I used this
>> arrangement for my Trylon and T2X; five washers gave me enough clearance for
>> my thin control cable.
>>
>> 73 de
>> Gene Smar AD3F
>> -----Original Message-----
>> From: n4kg@juno.com <n4kg@juno.com>
>> To: TOWERTALK@contesting.com <TOWERTALK@contesting.com>; wd3q@erols.com
>> <wd3q@erols.com>
>> Date: Monday, March 11, 2002 3:10 PM
>> Subject: Re: [Towertalk] Template for CDE Rotator Needed
>>
>>
>>> Another alternative is to mount the rotor on standoffs,
>>> oversize nuts can be used around the mounting bolts.
>>> This allows the cable to come out under the rotor,
>>> facilitating removal for service without having to first
>>> remove the cable.
>>>
>>> Tom N4KG
>>>
>>> On Mon, 11 Mar 2002 "Eric Rosenberg" <wd3q@erols.com> writes:
>>>>
>>>> My new (to me) roof tower has a solid (i.e., no holes) mounting
>>>> plate for a Yaesu rotator, which has its control cable coming
>>>> out the side.
>>>>
>>>> I use a TR-44 rotator, so I need to (have a metal shop) cut a
>>>> hole in the plate for the control cable to run through to the
>>>> bottom of the rotator.
>>>>
>>>> Where can I find a template for the rotor?
>>>>
>>>> Thanks in advance,
>>>>
>>>> Eric W3DQ
>>>> Washiongton, DC
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Towertalk mailing list
>>>> Towertalk@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>>
>>> ________________________________________________________________
>>> GET INTERNET ACCESS FROM JUNO!
>>> Juno offers FREE or PREMIUM Internet access for less!
>>> Join Juno today! For your FREE software, visit:
>>> http://dl.www.juno.com/get/web/.
>>> _______________________________________________
>>> Towertalk mailing list
>>> Towertalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
>> _______________________________________________
>> Towertalk mailing list
>> Towertalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
> Jim Rhodes K0XU
> jim@rhodesend.net
>
>
> --- StripMime Report -- processed MIME parts ---
> multipart/alternative
> text/plain (text body -- kept)
> text/html
> ---
>
> --__--__--
>
> Message: 10
> Date: Mon, 11 Mar 2002 22:14:13 -0700
> From: "Chris Adams" <n4vi@arrl.net>
> To: towertalk@contesting.com
> Organization: http://www.qsl.net/n4vi
> Subject: [Towertalk] reflection gain addendum
>
> The more I thought about it, the less I liked a vertical in free space
> as there is no ground in free space to drive the vertical "against".
> Also in my previous comparison the power delivered to the antennas was
> not adjusted to be equal.
>
> I redid the experiment with a vertical over perfect ground compared to a
> vertical dipole in free space. Both antennas were adjusted to resonance
> at apx 7MHz and the vertical was fed over perfect ground with 1amp
> current. The current in the vertical dipole was adjusted such that the
> power delivered to both antennas was the same (0.715amps, probably
> should be 0.707!). This yields the following results:
>
>
> 1. max gain of vertical with perfectly conducting ground (which
> occurs at zero degree azimuth) = 5.15 dbi
>
> 2. max gain of vertical dipole in free space (which also occurs at
> zero degrees aximuth) = 2.13 dbi
>
>
> I believe there's a weakness in this argument... my suspiscion is that
> it's related to setting the power delivered to both antennas as equal.
> That said, I can't figure it out at the moment and it sure seems the
> power should be equal, after all your transmitter doesn't know what
> antenna is out there!
>
> Oh well, when I get it figured out, if anyone still cares I'll post it!
> This thread may have gotten a little esoteric anyway.
>
>
> 73's
>
> chris, n4vi
>
>
> --__--__--
>
> Message: 11
> From: "Guy Olinger, K2AV" <k2av@contesting.com>
> To: <K4IA@aol.com>
> Cc: <towertalk@contesting.com>
> Subject: Re: [Towertalk] Grounding an Elevated vertical
> Date: Tue, 12 Mar 2002 00:21:44 -0500
>
> See below. 73, Guy.
>
> ----- Original Message -----
> From: <K4IA@aol.com>
> To: <k2av@contesting.com>
> ...snip...
>
>> If the ground screen is not connected to the antenna, what is the
> mechanism
>> by which reducing the ground current losses improves your signal?
> Where
>> would the ground current be going? Seems to me if it does not go
> back into
>> the antenna system, it is heating worms no matter how conductive you
> make the
>> earth below the antenna.
>
> It is not necessary for elements in an RF system to be literally
> interconnected by wires. If it were, transformers would not work.
> Yagi's would not work. No antenna with a parasitic element would work.
>
> There is a shielding effect that occurs inside or behind a system of
> conductors. For a given frequency, as the ground mesh or radial system
> get increasingly dense, the system goes from being buried conductors
> that are just passing current on to semiconducting (hence lossy) earth
> underneath to being a shield which prevents penetration, effectively
> behaving like a copper sheet. This occurs with 1/4 wave radials for
> their extent of coverage as the number of radials runs up to 60.
>
> I think I recall some stuff that W8JI did with 60 raised radials and
> being shielded underneath, but I'll let him chime in with that if he
> wants. Same effect.
>
>
>> Point 3, I understand but on the first bounce you are way beyond the
> radial
>> field. And, as you point out, ground clutter may have a substantial
> impact.
>> Perhaps the water and salt water verticals benefit from a clear line
> of sight
>> as much as from a conductive ground?
>
>> And herein lies another source of confusion for my overheated brain.
> If the
>> ground is highly conductive, why isn't absorbing energy instead of
> reflecting
>> it? Isn't that what conductive means?
>
> Loss in most of these discussions is a shorthand for resistive loss
> converted to heat, and not radiated. A perfect conductor in a yagi
> would have a current limited by "loss", but the "loss" would be
> entirely to RF radiation, which is desired. Hence the term radiation
> resistance. Absent radiation or transfer of power due to a transformer
> effect, increased current in a conductor is due to DECREASED resistive
> loss. If it's not heating the ground due to a shielding effect it HAS
> to go elsewhere. It doesn't have infinite current, so the only
> destination is radiation, hence the bounce.
>
>
>> Low resistance would equal high
>> current in the ground. Put another way, if I want to reflect light,
> I use a
>> mirror, which is highly resistive to light passing through. I could
> use a
>> piece of clear glass but I lose a lot of reflection because the glass
> is
>> highly conductive. Just another way of looking at it . . .
>
> Radio K4IA
> Craig Buck
> Fredericksburg, Virginia 22401 USA
>
> FISTS CW CLUB # 6702 CC 788 Diamond #64
> QRPARCI # 2550
> K1 #470 K2 #2460
>
>
>
>
> --__--__--
>
> Message: 12
> From: "Guy Olinger, K2AV" <k2av@contesting.com>
> To: "TowerTalk" <towertalk@contesting.com>
> Date: Tue, 12 Mar 2002 00:30:52 -0500
> Subject: [Towertalk] Fw: Antenna parts search
>
> This is a forward of a commercially related inquiry, but as it is for
> defense in a time of hostilities, and is not a classified inquiry, I
> thought I would pass it on.
>
> I seem to recall part numbers that start with 7300..., but just can't
> nail it down. Anyone recognize them, please respond direct to Mr. Ocha
> minus the nospam_ . I'll bet someone here recognizes them.
>
> Thanks, Guy.
>
>
> ----- Original Message -----
> From: "Philip Ochoa" <nospam_pochoa@fedef.com>
> To: <k2av@contesting.com>
> Sent: Monday, March 11, 2002 9:24 PM
> Subject: Antenna parts search
>
>
> Guy,
>
> I am hoping you might help me locate the following which I need to
> purchase. This
> is for a US Air Force installation in Egypt, but I do not have a
> manufacturer
> listed for these items. Do you recognize these part numbers as a
> particular
> manufacturer? If so, please respond or call me and let me know.
>
> P/N Description
> 730001 Tower section bar assembly
> 730004 Footpad
> 730046 Guyline Assy
> 730048 Guyline Spreader
> 730050 Tension winch Assy
>
>
> Best regards,
>
> Philip Ochoa nospam_pochoa@fedef.com
> FEDERAL DEFENSE INDUSTRIES, INC.
>
> Some signature material deleted.
>
>
>
>
> --__--__--
>
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
> End of Towertalk Digest
>