RadioBanter - Info needed TA-33SR Choke coil

RadioBanter (https://www.radiobanter.com/)

- Antenna (https://www.radiobanter.com/antenna/)

- - Info needed TA-33SR Choke coil (https://www.radiobanter.com/antenna/76857-info-needed-ta-33sr-choke-coil.html)

Info needed TA-33SR Choke coil

"Dan/W4NTI" wrote in message
k.net...
I am putting up my old TA-33SR by Mosley. I need to know how many
windings
are needed on the choke. I seem to remember 6" diameter, but not
the
amount of windings.

According to the manual there is no choke indicated at all.

Anyone know anything about this?

Dan/W4NTI

===================================
Dan, I am unable to help you.

Because, in common with most other people, I havn't the foggiest idea
what a TA-33SR is.

Questioners would do better by not depending on other people's
imagination. It takes only a few seconds to provide a little more
essential information. If you can't find the time then it can't matter
very much anyway.
----
Reg.

Dan:

Look he
http://bama.edebris.com/manuals/mosley/ta33sr

at the files:
00readme.txt (72 bytes)
ta33sr.pdf (322 KB)

John

On Mon, 22 Aug 2005 21:59:28 +0000, Dan/W4NTI wrote:

I am putting up my old TA-33SR by Mosley. I need to know how many windings
are needed on the choke. I seem to remember 6" diameter, but not the
amount of windings.

According to the manual there is no choke indicated at all.

Anyone know anything about this?

Dan/W4NTI

I am putting up my old TA-33SR by Mosley. I need to know how many windings
are needed on the choke. I seem to remember 6" diameter, but not the
amount of windings.

According to the manual there is no choke indicated at all.

Anyone know anything about this?

Dan/W4NTI

===================================
Dan, I am unable to help you.

Because, in common with most other people, I havn't the foggiest idea
what a TA-33SR is.

Questioners would do better by not depending on other people's
imagination. It takes only a few seconds to provide a little more
essential information. If you can't find the time then it can't matter
very much anyway.

Reg, even to me (a relative newbie) "Mosley TA-33SR" provides all of
the information needed to identify what Dan is talking about. A very
brief Google identifies as a triband trap beam. I have little doubt
that anyone who has ever owned one (and is thus likely to have the
direct information that Dan is looking for) would recognize it from
his description with no further description being required.

Dan - since Mosely's manual doesn't mention such a choke, and the
instruction sheet indicates a direct attachment of the coax to the
driven-element feedpoint terminals, I doubt that the details of the
choke are terribly critical. You could probably use any of the plans
on the net for an air-wound coaxial choke-balun. One plan I see uses
18-21 feet of coax, close-wound solenoid-style on a 5" PVC form
(stated to be good for 160-10 meters).

Another site (http://www.bcdxc.org/balun_information.htm#Ed,%20WA2SRQ)
has a table of air-core balun impedances, as a function of both
frequency and construction (turn count and diameter). This chart
suggests to me that 4 turns, 6 5/8" solenoid-wound might be a good
option for you, as its impedance peaks at around the 15-meter band and
is 500 ohms or better between 10 and 20 meters.

Some folks seem to prefer solenoid-wound air baluns, others prefer
scramble-wound. There seems to be a fair bit of disagreement as to
which style works better, and why.

The other choices are to use a different sort of balun (e.g. a W2DU
ferrite-bead choke), or none at all.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Dan/W4NTI wrote:
I am putting up my old TA-33SR by Mosley. I need to know how many windings
are needed on the choke. I seem to remember 6" diameter, but not the
amount of windings.

According to the manual there is no choke indicated at all.

Anyone know anything about this?

Dan/W4NTI

Hi Dan, The choke on a 3 band Yagi is to decrease feedline
radiation, a choke balun. If you don't use a choke balun, you could
have some pattern distortion, it would deviate from the classical 3
element Yagi pattern.
I think the rule of thumb is have enough chocking impedance on the
lowest band (20M) so that it is 10X the antenna impedance (50 ohm).
You wind your coax into a coil that will accomplish this.
The TA-33's that I have seen did not have the choke balun. In casual
Amateur operation of the TA-33 I doubt you would miss the choke, or
know if it was there or not.
Gary N4AST

"Dave Platt" wrote in message
...
I am putting up my old TA-33SR by Mosley. I need to know how
many windings
are needed on the choke. I seem to remember 6" diameter, but
not the
amount of windings.

According to the manual there is no choke indicated at all.

Anyone know anything about this?

Dan/W4NTI

===================================
Dan, I am unable to help you.

Because, in common with most other people, I havn't the foggiest
idea
what a TA-33SR is.

Questioners would do better by not depending on other people's
imagination. It takes only a few seconds to provide a little more
essential information. If you can't find the time then it can't
matter
very much anyway.

Reg, even to me (a relative newbie) "Mosley TA-33SR" provides all of
the information needed to identify what Dan is talking about. A
very
brief Google identifies as a triband trap beam. I have little doubt
that anyone who has ever owned one (and is thus likely to have the
direct information that Dan is looking for) would recognize it from
his description with no further description being required.

Dan - since Mosely's manual doesn't mention such a choke, and the
instruction sheet indicates a direct attachment of the coax to the
driven-element feedpoint terminals, I doubt that the details of the
choke are terribly critical. You could probably use any of the
plans
on the net for an air-wound coaxial choke-balun. One plan I see
uses
18-21 feet of coax, close-wound solenoid-style on a 5" PVC form
(stated to be good for 160-10 meters).

Another site
(http://www.bcdxc.org/balun_information.htm#Ed,%20WA2SRQ)
has a table of air-core balun impedances, as a function of both
frequency and construction (turn count and diameter). This chart
suggests to me that 4 turns, 6 5/8" solenoid-wound might be a good
option for you, as its impedance peaks at around the 15-meter band
and
is 500 ohms or better between 10 and 20 meters.

Some folks seem to prefer solenoid-wound air baluns, others prefer
scramble-wound. There seems to be a fair bit of disagreement as to
which style works better, and why.

The other choices are to use a different sort of balun (e.g. a W2DU
ferrite-bead choke), or none at all.

--
Dave Platt
==================================

Dave, having learned from you, a newbie, not from the enquirer, what a
TA-33SR is, and having inspected the website you specify, I am a
little wiser from reading the baffle-gab.

I agree with your recomendations. Just get a hank of coax, suspend it
in the feedline and away you go.

But it may be more mechanically convenient and electrically better to
wind a few turns of coax or Radio Shack twin speaker wire around a
ferrite toroidal core.

Or possibly do without a balun altogether. Try it and see what
happens. It's so easy to do.
----
Reg.

On Mon, 22 Aug 2005 21:18:30 -0400, BillJ wrote:

Dan/W4NTI wrote:
I am putting up my old TA-33SR by Mosley. I need to know how many windings
are needed on the choke. I seem to remember 6" diameter, but not the
amount of windings.

According to the manual there is no choke indicated at all.

Anyone know anything about this?

Dan/W4NTI

My TA-33 manual calls for 5 turns at 6 inch diameter
Bill, W3FI

That your TA-33 manual calls for a 5-turn 6" diameter balun fabbed
from coax is welcome news, Bill, Mr. Mosely must have gotten religion
lately. I had a 33 when they were first made available, but no balun
was included. So I had a talk with Mr. Mosely (I've forgotten his
first name) and asked him why no balun. He became irate when I
admonished him for excluding the balun. He said his antennas were
designed to not need a balun, and he admonished me for claiming they
needed a balun to avoid pattern distortion due to unwanted radiation
from the feedline. He kept that same erroneous viewpoint for as long
as I know, until your manual now calls for a balun. Will wonders never
cease!

Walt, W2DU

Mr. Moseley's first name was Carl. He was known on the air as "the Old Man
Himself." I worked him on 40 cw when I was a novice in 1967. He has probably been
a silent key for 30 years or longer. I don't remember his call but I have his card
in my card file. K4AVO

Walter Maxwell wrote:

On Mon, 22 Aug 2005 21:18:30 -0400, BillJ wrote:

Dan/W4NTI wrote:
I am putting up my old TA-33SR by Mosley. I need to know how many windings
are needed on the choke. I seem to remember 6" diameter, but not the
amount of windings.

According to the manual there is no choke indicated at all.

Anyone know anything about this?

Dan/W4NTI

My TA-33 manual calls for 5 turns at 6 inch diameter
Bill, W3FI

That your TA-33 manual calls for a 5-turn 6" diameter balun fabbed
from coax is welcome news, Bill, Mr. Mosely must have gotten religion
lately. I had a 33 when they were first made available, but no balun
was included. So I had a talk with Mr. Mosely (I've forgotten his
first name) and asked him why no balun. He became irate when I
admonished him for excluding the balun. He said his antennas were
designed to not need a balun, and he admonished me for claiming they
needed a balun to avoid pattern distortion due to unwanted radiation
from the feedline. He kept that same erroneous viewpoint for as long
as I know, until your manual now calls for a balun. Will wonders never
cease!

Walt, W2DU