Good grief. Sure it will work, but,
how about a three terminal regulator?
Or even a resistor and Zener?
WL
-----Original Message-----
From: towertalk-request@contesting.com
Sent: Tuesday, January 21, 2014 12:00 PM
To: towertalk@contesting.com
Subject: TowerTalk Digest, Vol 133, Issue 46
Send TowerTalk mailing list submissions to
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When replying, please edit your Subject line so it is more specific
than "Re: Contents of TowerTalk digest..."
Today's Topics:
1. Molded connectors (Carol Richards)
2. 15M6DX boom to mast plate (Jorge Diez - CX6VM)
3. Re: 15M6DX boom to mast plate (Hector Garcia,XE2K)
4. Protection of a preamp (Lizeth Norman)
5. Re: 15M6DX boom to mast plate (Jorge Diez - CX6VM)
6. Re: Protection of a preamp (Patrick Greenlee)
7. Re: Protection of a preamp (TexasRF@aol.com)
----------------------------------------------------------------------
Message: 1
Date: Mon, 20 Jan 2014 20:13:54 -0500
From: "Carol Richards" <n2mm@comcast.net>
To: <towertalk@contesting.com>
Subject: [TowerTalk] Molded connectors
Message-ID: <7E39CBF873B4471A93CE09119856C61E@HPDesktop>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
I have been using 8-pin molex type trailer cables. Both the male and female
come with #12 or #14 gauge stranded pigtails, about 3 feet long. They work
great/
I got them from wiringproducts.com
Carol
------------------------------
Message: 2
Date: Tue, 21 Jan 2014 10:18:30 -0200
From: "Jorge Diez - CX6VM" <cx6vm.jorge@gmail.com>
To: <TOWERTALK@contesting.com>
Cc: 'Kurt Andress' <k7nv@contesting.com>, 'Stan Stockton'
<wa5rtg@gmail.com>
Subject: [TowerTalk] 15M6DX boom to mast plate
Message-ID: <52de659d.269aec0a.3192.ffffe275@mx.google.com>
Content-Type: text/plain; charset="us-ascii"
Hello
I am reinstalling a 15M6DX. Boom is 2.5 inches
The mast to boom plate seems very small for a 44 ft boom antenna, is just 8
x 8 inches
Anyone replaced this factory plate with another option? Where to find it?
Thanks,
Jorge
CX6VM/CW5W
------------------------------
Message: 3
Date: Tue, 21 Jan 2014 08:02:41 -0800 (PST)
From: "Hector Garcia,XE2K" <j_hector_garcia@sbcglobal.net>
To: Jorge Diez - CX6VM <cx6vm.jorge@gmail.com>,
"TOWERTALK@contesting.com" <TOWERTALK@contesting.com>
Cc: 'Kurt Andress' <k7nv@contesting.com>, 'Stan Stockton'
<wa5rtg@gmail.com>
Subject: Re: [TowerTalk] 15M6DX boom to mast plate
Message-ID:
<1390320161.25825.YahooMailNeo@web181602.mail.ne1.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
Jorge
You will like to see this
http://www.dxengineering.com/techarticles/antennaconstruction/modifications-to-the-m2-model-40m4lldd
?
J.Hector Garcia ?XE2K / AD6D
Mexicali B.C DM22fp / El Centro
P.O.Box 73
El Centro CA 92244-0073
http://xe2k.net
Tweeter @XE2K
________________________________
From: Jorge Diez - CX6VM <cx6vm.jorge@gmail.com>
To: TOWERTALK@contesting.com
Cc: 'Kurt Andress' <k7nv@contesting.com>; 'Stan Stockton' <wa5rtg@gmail.com>
Sent: Tuesday, January 21, 2014 4:18 AM
Subject: [TowerTalk] 15M6DX boom to mast plate
Hello
I am reinstalling a 15M6DX. Boom is 2.5 inches
The mast to boom plate seems very small for a 44 ft boom antenna, is just 8
x 8 inches
Anyone replaced this factory plate with another option?? Where to find it?
Thanks,
Jorge
CX6VM/CW5W
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TowerTalk mailing list
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http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
Message: 4
Date: Tue, 21 Jan 2014 11:14:16 -0500
From: Lizeth Norman <normanlizeth@gmail.com>
To: towertalk <towertalk@contesting.com>
Subject: [TowerTalk] Protection of a preamp
Message-ID:
<CAJUhCTO-LdUJHScaDb4FCWSGz_eq7RyX2zyK8iOtTiSH4Hj+WQ@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Hi all!
I have a preamp that I switch in and out with a pair of spdt coaxial
relays. The NC positions pass through and the NO positions hold the preamp.
The relays are +24Vdc and the preamp needs ideally 12Vdc.
Presently, I have the preamps hooked up to +24Vdc and they are frying.
What I'd like to do is when I key the relay, also feed the preamp through
20 diodes to drop the Voltage to something respectable. Possibly using a
100uF cap across the preamp.
Am I asking for trouble? Do dragons live here?
Norm n3ykf
------------------------------
Message: 5
Date: Tue, 21 Jan 2014 14:23:38 -0200
From: "Jorge Diez - CX6VM" <cx6vm.jorge@gmail.com>
To: <TOWERTALK@contesting.com>
Subject: Re: [TowerTalk] 15M6DX boom to mast plate
Message-ID: <52de9f11.269aec0a.3192.7a10@mx.google.com>
Content-Type: text/plain; charset="us-ascii"
Wow!
They use the same plate in this monster 4 elements 40 mts yagi!, incredible.
Thanks for the link, just what I am looking for
73,
Jorge
De: Hector Garcia,XE2K [mailto:j_hector_garcia@sbcglobal.net]
Enviado el: martes, 21 de enero de 2014 02:03 p.m.
Para: Jorge Diez - CX6VM; TOWERTALK@contesting.com
CC: 'Kurt Andress'; 'Stan Stockton'
Asunto: Re: [TowerTalk] 15M6DX boom to mast plate
Jorge
You will like to see this
http://www.dxengineering.com/techarticles/antennaconstruction/modifications-
to-the-m2-model-40m4lldd
J.Hector Garcia XE2K / AD6D
Mexicali B.C DM22fp / El Centro
P.O.Box 73
El Centro CA 92244-0073
http://xe2k.net
Tweeter @XE2K
_____
From: Jorge Diez - CX6VM <cx6vm.jorge@gmail.com>
To: TOWERTALK@contesting.com
Cc: 'Kurt Andress' <k7nv@contesting.com>; 'Stan Stockton' <wa5rtg@gmail.com>
Sent: Tuesday, January 21, 2014 4:18 AM
Subject: [TowerTalk] 15M6DX boom to mast plate
Hello
I am reinstalling a 15M6DX. Boom is 2.5 inches
The mast to boom plate seems very small for a 44 ft boom antenna, is just 8
x 8 inches
Anyone replaced this factory plate with another option? Where to find it?
Thanks,
Jorge
CX6VM/CW5W
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TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
Message: 6
Date: Tue, 21 Jan 2014 10:25:08 -0600
From: "Patrick Greenlee" <patrick_g@windstream.net>
To: "Lizeth Norman" <normanlizeth@gmail.com>, "towertalk"
<towertalk@contesting.com>
Subject: Re: [TowerTalk] Protection of a preamp
Message-ID: <83064646D5CF487AA6DB6FE56CE66B6D@PatrickLaptop>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Well that is one way. Another is to use a (one, 1 , ein un) Zener diode to
subtract out the difference. Another way is to measure the current draw of
the amps when operated on proper voltage and then calculate the value of a
series resistor required to drop the excess voltage at that current.
For your convenience: I=E/R P=IE (don't forget to calc the power
dissipated by the R so you can size it (them if you use more than one.)
A cap across the power connections at the amps won't hurt but probably not
THAT BIG.
Patrick NJ5G
-----Original Message-----
From: Lizeth Norman
Sent: Tuesday, January 21, 2014 10:14 AM
To: towertalk
Subject: [TowerTalk] Protection of a preamp
Hi all!
I have a preamp that I switch in and out with a pair of spdt coaxial
relays. The NC positions pass through and the NO positions hold the preamp.
The relays are +24Vdc and the preamp needs ideally 12Vdc.
Presently, I have the preamps hooked up to +24Vdc and they are frying.
What I'd like to do is when I key the relay, also feed the preamp through
20 diodes to drop the Voltage to something respectable. Possibly using a
100uF cap across the preamp.
Am I asking for trouble? Do dragons live here?
Norm n3ykf
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TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
Message: 7
Date: Tue, 21 Jan 2014 11:31:03 -0500 (EST)
From: TexasRF@aol.com
To: normanlizeth@gmail.com, towertalk@contesting.com
Subject: Re: [TowerTalk] Protection of a preamp
Message-ID: <7a632.26a63011.400ffac6@aol.com>
Content-Type: text/plain; charset="US-ASCII"
Norm, yes, there are dragons here!
Relay isolation has to be sufficient keep the rf voltage from destroying
the preamp. Often times a single relay doesn't give enough isolation and
tandem relays are required. This applies to both the input and output of
the
preamp.
Another issue is the relays will generate an inductive voltage kick at turn
off. You can add filtering and clamping diodes but the spike can happen so
quickly that the preamp still gets a hit before the protection circuit
does it's job.
Timing is critical. The relays need enough time for the contacts to settle
before rf is present.
VHF/UHF operators typically use a sequencer to turn things on/off in the
right order and time to protect the preamp. The requirements for complete
protection are not trivial!
73,
Gerald K5GW
In a message dated 1/21/2014 8:14:48 A.M. Pacific Standard Time,
normanlizeth@gmail.com writes:
Hi all!
I have a preamp that I switch in and out with a pair of spdt coaxial
relays. The NC positions pass through and the NO positions hold the preamp.
The relays are +24Vdc and the preamp needs ideally 12Vdc.
Presently, I have the preamps hooked up to +24Vdc and they are frying.
What I'd like to do is when I key the relay, also feed the preamp through
20 diodes to drop the Voltage to something respectable. Possibly using a
100uF cap across the preamp.
Am I asking for trouble? Do dragons live here?
Norm n3ykf
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------------------------------
Subject: Digest Footer
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------------------------------
End of TowerTalk Digest, Vol 133, Issue 46
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