twinlead tuning indicators
 

On Mon, 31 May 2010 15:20:03 -0700, "rb" wrote:

Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show how
it's doing.

Hi OM,

What you call fluorescent, I assume, must mean a small NE2 neon
indicator bulb which would be suitable to what you describe.

If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a small
flourescent bulb will do this or not.

It is going to be an indication of "something."


If radiation is cancelled, not sure how it would fire.

Within close proximity (about 3 to 5 times the wire separation), you
still have a sense of each wire. Further away, there is so little
difference in distance to either of them, that they both add with
cancellation.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had SWR on
the other side. Neither light being lit meant good SWR.

This must be the cobwebs you speak of. Other than LEDs (and I think
you would have specifically said so if your indicators were these),
lamps have no sense of current direction. Example, what would happen
if you reversed the plug to your table lamp? Would it suck light?
Have you ever put in a fluorescent bulb with the wrong polarity?

73's
Richard Clark, KB7QHC

twinlead tuning indicators
 

Richard Clark wrote in
:

Example, what would happen
if you reversed the plug to your table lamp? Would it suck light?

As it is, they suck dark. Right?

https://www.msu.edu/user/dynicrai/physics/dark.htm

twinlead tuning indicators
 

Richard Clark Inscribed thus:

On Mon, 31 May 2010 15:20:03 -0700, "rb" wrote:

Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to
show how it's doing.

Hi OM,

What you call fluorescent, I assume, must mean a small NE2 neon
indicator bulb which would be suitable to what you describe.

If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a
small flourescent bulb will do this or not.

It is going to be an indication of "something."


If radiation is cancelled, not sure how it would fire.

Within close proximity (about 3 to 5 times the wire separation), you
still have a sense of each wire. Further away, there is so little
difference in distance to either of them, that they both add with
cancellation.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had
SWR on the other side. Neither light being lit meant good SWR.

This must be the cobwebs you speak of. Other than LEDs (and I think
you would have specifically said so if your indicators were these),
lamps have no sense of current direction. Example, what would happen
if you reversed the plug to your table lamp? Would it suck light?
Have you ever put in a fluorescent bulb with the wrong polarity?

73's
Richard Clark, KB7QHC

I have vague recollections of a reflectometer using diodes, lamps and
300ohm twin feeder. Maybe in an old copy of Radcom...

73's
--
Best Regards:
Baron.

twinlead tuning indicators
 

Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show how
it's doing. If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a small
flourescent bulb will do this or not.

If radiation is cancelled, not sure how it would fire.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had SWR on
the other side. Neither light being lit meant good SWR.

twinlead tuning indicators
 

In article , "rb"
wrote:

Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show how
it's doing. If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a small
flourescent bulb will do this or not.

If radiation is cancelled, not sure how it would fire.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had SWR on
the other side. Neither light being lit meant good SWR.

RB-

My cobwebs are probably worse than yours. As a teenager back in the
50s, I used a "Full Windom" antenna (off-center-fed-dipole) fed with 300
Ohm TV twin lead.

The SWR measurement circuit I used probably came from an ARRL
publication. It consisted of two 6 Volt dial lamps connected to each
end of a section of twin lead. I think it was two or three feet long.
The whole thing was taped to the transmission line. There was a
connection at the center of this on one side to one side of the
transmission line.

As I understood it, one lamp was supposed to glow and not the other. I
think both of mine glowed, but one was definitely brighter. Of coarse I
did not know what I was doing and had no real understanding of SWR. I
made contacts, so never worried about it!

Using a fluorescent tube, I would expect it might glow at points along
the transmission line where voltage was high and extinguish where
voltage was low. With a low SWR, there would be no high voltage points.
Or maybe no nulls?

Fred
K4DII

twinlead tuning indicators
 

When I feed twinlead, seems I might use a small fluorescent bulb to
show how it's doing.
....[snip]....

See:

"The Eyes Have It; Making S.W.R. Measurements with the Twin-Lamp"
on page 50 of the October, 1948, issue of QST.

"The 'Coax Twin-Lamp', A Simple S.W.R. Indicator for Solid Line"
on page 25 of the November, 1948, issue of QST.

"Measuring Center Impedance of Antennas with the 'Twin-Lamp" on
page 67 of the May, 1950, issue of QST.

"Old Reliable" on page 67 of the April, 1958, issue of CQ.

--W0PBV.

--
-- Myron A. Calhoun.
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
NRA Life Member & Certified Instructor for Rifle, Pistol, & Home Firearm Safety
Also Certified Instructor for the Kansas Concealed-Carry Handgun (CCH) license

twinlead tuning indicators
 

On 05/31/2010 03:20 PM, rb wrote:
Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show how
it's doing. If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a small
flourescent bulb will do this or not.

If radiation is cancelled, not sure how it would fire.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had SWR on
the other side. Neither light being lit meant good SWR.


I can only relate an experience I had in my house in Minnesota. We had a
long hallway and I could just shuffle my feet and the fluorescent light
I was carrying lit up from the accumulation of charge. Free, well almost
free light. A guy in the S.F. bay area has a house near a radio
transmitter and his garage is pretty well lit by 4 foot tubes he has put
around.
YMMV.

twinlead tuning indicators
 

On 05/31/2010 03:39 PM, Fred McKenzie wrote:
In ,
wrote:

Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show how
it's doing. If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a small
flourescent bulb will do this or not.

If radiation is cancelled, not sure how it would fire.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had SWR on
the other side. Neither light being lit meant good SWR.

RB-

My cobwebs are probably worse than yours. As a teenager back in the
50s, I used a "Full Windom" antenna (off-center-fed-dipole) fed with 300
Ohm TV twin lead.

The SWR measurement circuit I used probably came from an ARRL
publication. It consisted of two 6 Volt dial lamps connected to each
end of a section of twin lead. I think it was two or three feet long.
The whole thing was taped to the transmission line. There was a
connection at the center of this on one side to one side of the
transmission line.

As I understood it, one lamp was supposed to glow and not the other. I
think both of mine glowed, but one was definitely brighter. Of coarse I
did not know what I was doing and had no real understanding of SWR. I
made contacts, so never worried about it!

Try this.. I had an Ampex tube amplifier driving a high voltage
transformer and as the music danced (in my head) the patterns were
dancing to the same beat. I just drove the input of the Ampex with the
output audio line. Yes, that was in the 70's and yes we were all stoned.
I don't think that anyone else tried that combination, but it was way cool.
Bill Baka

Using a fluorescent tube, I would expect it might glow at points along
the transmission line where voltage was high and extinguish where
voltage was low. With a low SWR, there would be no high voltage points.
Or maybe no nulls?

Fred
K4DII

twinlead tuning indicators
 

On 05/31/2010 03:51 PM, Bill Baka wrote:
On 05/31/2010 03:39 PM, Fred McKenzie wrote:
In ,
wrote:

Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to
show how
it's doing. If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a small
flourescent bulb will do this or not.

If radiation is cancelled, not sure how it would fire.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had SWR on
the other side. Neither light being lit meant good SWR.

RB-

My cobwebs are probably worse than yours. As a teenager back in the
50s, I used a "Full Windom" antenna (off-center-fed-dipole) fed with 300
Ohm TV twin lead.

The SWR measurement circuit I used probably came from an ARRL
publication. It consisted of two 6 Volt dial lamps connected to each
end of a section of twin lead. I think it was two or three feet long.
The whole thing was taped to the transmission line. There was a
connection at the center of this on one side to one side of the
transmission line.

As I understood it, one lamp was supposed to glow and not the other. I
think both of mine glowed, but one was definitely brighter. Of coarse I
did not know what I was doing and had no real understanding of SWR. I
made contacts, so never worried about it!

Try this.. I had an Ampex tube amplifier driving a high voltage
transformer and as the music danced (in my head) the patterns were
dancing to the same beat. I just drove the input of the Ampex with the
output audio line. Yes, that was in the 70's and yes we were all stoned.
I don't think that anyone else tried that combination, but it was way cool.
Bill Baka

Using a fluorescent tube, I would expect it might glow at points along
the transmission line where voltage was high and extinguish where
voltage was low. With a low SWR, there would be no high voltage points.
Or maybe no nulls?

Fred
K4DII

Whatever it was it was sure pretty and tube had ripples from both ends
that we could just watch. You would almost have to see it to believe it.
Kind of like visible standing waves going the length of the tube.
I think that kind of thing would kill any new solid state amps.
Bill

twinlead tuning indicators
 

"Richard Clark" wrote in message
...
On Mon, 31 May 2010 15:20:03 -0700, "rb" wrote:

Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show
how
it's doing.

Hi OM,

What you call fluorescent, I assume, must mean a small NE2 neon
indicator bulb which would be suitable to what you describe.

If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a small
flourescent bulb will do this or not.

It is going to be an indication of "something."


If radiation is cancelled, not sure how it would fire.

Within close proximity (about 3 to 5 times the wire separation), you
still have a sense of each wire. Further away, there is so little
difference in distance to either of them, that they both add with
cancellation.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had SWR on
the other side. Neither light being lit meant good SWR.

This must be the cobwebs you speak of. Other than LEDs (and I think
you would have specifically said so if your indicators were these),
lamps have no sense of current direction. Example, what would happen
if you reversed the plug to your table lamp? Would it suck light?
Have you ever put in a fluorescent bulb with the wrong polarity?

73's
Richard Clark, KB7QHC
-
The LEDs that suck light are normally referred to as DEDs (Dark Emitting
Diodes)

twinlead tuning indicators
 

On May 31, 8:55*pm, "Wayne" wrote:
"Richard Clark" wrote in message

...

On Mon, 31 May 2010 15:20:03 -0700, "rb" wrote:

Memory has usual cob webs. *Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show
how
it's doing.

Hi OM,

What you call fluorescent, I assume, must mean a small NE2 neon
indicator bulb which would be suitable to what you describe.

*If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? * *Can't recall if a small
flourescent bulb will do this or not.

It is going to be an indication of "something."

If radiation is cancelled, not sure how it would fire.

Within close proximity (about 3 to 5 times the wire separation), *you
still have a sense of each wire. *Further away, there is so little
difference in distance to either of them, that they both add with
cancellation.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. * One way you had SWR on one side; * the other way you had SWR on
the other side. * Neither light being lit meant good SWR.

This must be the cobwebs you speak of. *Other than LEDs (and I think
you would have specifically said so if your indicators were these),
lamps have no sense of current direction. *Example, what would happen
if you reversed the plug to your table lamp? *Would it suck light?
Have you ever put in a fluorescent bulb with the wrong polarity?

73's
Richard Clark, KB7QHC

-
The LEDs that suck light are normally referred to as DEDs (Dark Emitting
Diodes)

Hi Bill,

I just now ran into one of your earlier posts regarding insomnia. I
have some important info for you, which I'll email to you if you'll
give me your email address in a email to me, which is .

Walt

twinlead tuning indicators
 

On May 31, 10:13*pm, walt wrote:
On May 31, 8:55*pm, "Wayne" wrote:



"Richard Clark" wrote in message

.. .

On Mon, 31 May 2010 15:20:03 -0700, "rb" wrote:

Memory has usual cob webs. *Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show
how
it's doing.

Hi OM,

What you call fluorescent, I assume, must mean a small NE2 neon
indicator bulb which would be suitable to what you describe.

*If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? * *Can't recall if a small
flourescent bulb will do this or not.

It is going to be an indication of "something."

If radiation is cancelled, not sure how it would fire.

Within close proximity (about 3 to 5 times the wire separation), *you
still have a sense of each wire. *Further away, there is so little
difference in distance to either of them, that they both add with
cancellation.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. * One way you had SWR on one side; * the other way you had SWR on
the other side. * Neither light being lit meant good SWR.

This must be the cobwebs you speak of. *Other than LEDs (and I think
you would have specifically said so if your indicators were these),
lamps have no sense of current direction. *Example, what would happen
if you reversed the plug to your table lamp? *Would it suck light?
Have you ever put in a fluorescent bulb with the wrong polarity?

73's
Richard Clark, KB7QHC

-
The LEDs that suck light are normally referred to as DEDs (Dark Emitting
Diodes)

Hi Bill,

I just now ran into one of your earlier posts regarding insomnia. I
have some important info for you, which I'll email to you if you'll
give me your email address in a email to me, which is .

Walt

Darn, Bill, I don't know why this forum deletes part of an email
delivered in the text of a msg. The word preceding the @ is walt.

Walt

twinlead tuning indicators
 

On Mon, 31 May 2010 , walt wrote:

I just now ran into one of your earlier posts regarding insomnia. I
have some important info for you, which I'll email to you if you'll
give me your email address in a email to me, which is .

Walt

Darn, Bill, I don't know why this forum deletes part of an email
delivered in the text of a msg. The word preceding the @ is walt.

Walt

This is not a forum -- this is a newsgroup on usenet. If you wouldn't
use the google group kludge to attempt access into usenet, you would not
see such additional kludginess in your postings. And, your postings are
more apt to be seen by folks that don't killfile googlegrooper postings
outright due to all the spam that flows in from that seweer.

twinlead tuning indicators
 

On Mon, 31 May 2010 18:39:11 -0400, Fred McKenzie
wrote:

It consisted of two 6 Volt dial lamps connected to each
end of a section of twin lead. I think it was two or three feet long.
The whole thing was taped to the transmission line. There was a
connection at the center of this on one side to one side of the
transmission line.

Hi All,

This and Myron's reference appear to fill in all the blanks and should
brush away the cobwebs.

What is described above appears to be that of a directional coupler. I
would suspect that the connection between it and the line is through a
capacitor, and the line proximity serves the inductive coupling. I
also presume the "transmission line" was also twin line, otherwise
none of this would work. The action of the directional coupler is
what separates the forward and reflected energies.

73's
Richard Clark, KB7QHC

twinlead tuning indicators
 

Bruce in alaska wrote:

Up here in Alaska, we used to use the SAT Balanced Antenna Tuners to feed
300 Ohm Twin-lead Dipoles, cut for the Lowest Frequency Channel in the
Radio. then use a Bird WattMeter in the Coax Feeding the Tuner, while
doing the Setup. After things were setup for each channel and Band in
the Radio, we would tape a pair of NE2's, one on each side of the
Twin-lead at the closest Voltage Node to the Tuner. then the Operator
could watch the RF Output on the NE2's. worked fair... for the those
days...

Shucks, up there in Alaska, KL7BFB ("Barrel Full of Beer") ran a
(Alaska?) gallon of AM to a lazy H antenna. It had a fluorescent tube
taped to each of the four wire ends, which lit up nicely when he hit the
mike button. Ah, those were the days. . .

'Course I used to run out onto the runway at the Juneau airport to
retrieve ducks I'd shot. Bet you can't do that any more!

Roy Lewallen, W7EL

twinlead tuning indicators
 

In article ,
Roy Lewallen wrote:

'Course I used to run out onto the runway at the Juneau airport to
retrieve ducks I'd shot. Bet you can't do that any more!

Roy Lewallen, W7EL

Nope, you sure can't..... Years ago I was servicing an Alascom Alaska
Public Fixed Transmitter in Bethel that ran a Full Gallon on 2, 3, 5, &
8 MHz. The Operator I knew from a few years earlier, also was a Ham, and
was using one of the OLD Rhombics, From the WWII days, to work the West
Coast with 2 watts from a Northern Radio SSB Handheld Prototype on 40
meters. He was said to have the strongest Signal on the band as the sun
set each night. They just don't make antennas like those anymore.

--
Bruce in alaska
add path after fast to reply

twinlead tuning indicators
 

On Mon, 31 May 2010 15:20:03 -0700, "rb" wrote:

Memory has usual cob webs. Help clear it.......

When I feed twinlead, seems I might use a small fluorescent bulb to show how
it's doing. If a small fluorescent bulb will do this, do I just tune for
"max smoke" while holding it near the twinlead? Can't recall if a small
flourescent bulb will do this or not.

If radiation is cancelled, not sure how it would fire.

I vaguely remember we used to use twin lamps, wired backwards for this
purpose. One way you had SWR on one side; the other way you had SWR on
the other side. Neither light being lit meant good SWR.


I have an old '58 copy of the ARRL handbook, and page 534 has the
"Twin-Lamp" tuning indicator for balanced line. It consists of a
couple of low-voltage flashlight bulbs wired to a short piece of
balanced line to insert into the transmission line.

Solder the tips of two flashlight bulbs together, wire that tip joint
to the short length of balanced line, and wire the bulb shells to the
line, too. Insert the device into the transmission line for tuning.

Fire things up. For minimum SWR, the bulb nearest the transmitter will
be bright, the bulb nearest the antenna will be dark. Or if the two
bulbs are glowing with the same brilliance, you have high SWR.

Bob
k5qwg

twinlead tuning indicators
 

On Jun 2, 7:26*pm, Bob wrote:
Fire things up. For minimum SWR, the bulb nearest the transmitter will
be bright, the bulb nearest the antenna will be dark. Or if the two
bulbs are glowing with the same brilliance, you have high SWR.

I built one of those things in the 50's. I was feeding a resonant
1/2WL 40m with 1/2WL of TV twinlead. I could never get the reflected
bulb to go dim, no matter what I did, because 300/50 = an SWR of 6:1.
My reflected power was more than 1/2 of the forward power. It was only
four years later as I got close to a EE degree, that I understood why
the reflected bulb would never go dim. :-)
--
73, Cecil, w5dxp.com