Old buzzard porcelain spreaders

[VE7 Kilohertz]

I have about 10 or so of these little gems. I can only see one way to wind the wire thru it. Does it look right to you?  These must be from the 50's??  Nice Logo from EF Johnson.

I imagine the crossover of wires will not disturb the impeadance?  It also may help keep balance or

Cool.

Cheers

Paul

[N3DRB The Derb]

probably more from the late 20's to very early 30's judging by the logo. A quick look in that era of QST will date them,but Johnson stopped using that logo after WW2 IIRC. Thats the right way to put the wires. Nothing says "old and buzzardly" more than glazed porcelain, except maybe colored glass insulators. I had a dipole once that used 3 those green glass insulators, and my signal was +67db louder than it was with the plastic ones. no, really. 

cool spreaders.

[WA1GFZ]

I thought those insulators were for 4 wire transmission line???

[Ed-VA3ES]

Paul, that's  a "transposition" insulator, used to transpose the wires over a long run.   Used more often on open-wire, 600 ohm lines, than RF transmision lines, but we use them too where the transmision lines  run close to  metal structures, and we want to  eliminate the proximity effects. 

I have done  that with my 450 ohm ladderline, by  gently twisting the line in it's run down the tower.  It's held by home-made stand-offs. every three feet.

I have a box of ceramic Johnson  spreaders designed for 4"  line.

[WA1GFZ]

My collection of 4 inch spreaders goes back to the 60s when I paid 55 cents each for them at Hatry's

[k4kyv]

I have one or two.  They are made  for transposed line.  I seem to recall some articles from just before or just after the War that used them.  The problem I see regarding high power (mine are made for about 1 1/2" spacing of the wires), as shown in the photo, is that the wires come much closer together where they cross over, than they are spaced in the line.

Nothing says "old and buzzardly" more than glazed porcelain, except maybe colored glass insulators.

To add to the "old buzzardly" look, use BROWN glazed porcelain as opposed to white glazed. 

BTW, in my parts collection I have several brown glazed EF Johnson type 211 tube sockets (fit 211's 250TH's, 450T's, 810's etc).  Does anyone have any brown glazed EF Johnson type 210 sockets (the smaller twist-lock ones that fit 210's, 811A's, 866A's, etc) that you would be willing to sell or trade?

[Vortex Joe - N3IBX]

Those spreaders you have are very kewl!

Don, K4KYV: Like you, I have the brown Johnson 50W sockets. Unfortunately, all of my sockets for a #10 tube are white, with the nickel plated collar.

Regards,
            Joe Cro N3IBX

[Vortex Joe - N3IBX]

I thought those insulators were for 4 wire transmission line???

Frank,
        Do you mean the terminating insulator(s) for a fan type dipole?

[k4kyv]

Don, K4KYV: Like you, I have the brown Johnson 50W sockets. Unfortunately, all of my sockets for a #10 tube are white, with the nickel plated collar.

The 210 sockets are listed in the catalogues up to about 1936 as available in both white and brown.  But I have never seen one.  I wonder if they even manufactured any.  I do have a pair made by another manufacturer, but the glazing is black instead of brown.

Have you ever noticed that most of the brown glazed "50 watt" sockets wipe both sides of all four tube pins, whereas the more modern white ones only wipe one side of the grid and plate pins, but wipe both side of the filament pins?

Of course, many tubes, like the 810 and 250T series have external grid and plate caps, so the base pins are used for the filament only.

[Vortex Joe - N3IBX]

Don, K4KYV: Like you, I have the brown Johnson 50W sockets. Unfortunately, all of my sockets for a #10 tube are white, with the nickel plated collar.

Have you ever noticed that most of the brown glazed "50 watt" sockets wipe both sides of all four tube pins, whereas the more modern white ones only wipe one side of the grid and plate pins, but wipe both side of the filament pins?

Don,
     Yes, I've noticed that. I assumed they were made for side grid tubes. Maybe.
     Another 50W socket/tube anomoly is that not all 50W class tubes will fit all sockets. I have a pair of DeForest 845's and 203A's that won't fit all of the 50W sockets I have. I have a good variey of EF Johnson,Birnbach,Leeds radio and others. The DeForest tubes won't fit all of the sockets. They're just a tad too large.

[N3DRB The Derb]

my memory has been jogged. many will forget as I did that ef johnson made antenna parts in the early 30's that used these spreaders. I remember seeing the ads in QST for them. the transposition was exactly so that the wires would not act like a transmission line. They were supposed to radiate.  I think the name "Hi-Q" was used to describe them. They were mostly for directional wire antennas like lazy H's and such for 20 thru 5 meters.

[KA1ZGC]

the transposition was exactly so that the wires would not act like a transmission line. They were supposed to radiate.  I think the name "Hi-Q" was used to describe them. They were mostly for directional wire antennas like lazy H's and such for 20 thru 5 meters.

Hmmn... I wonder if one could construct a sort of open-wire collinear with those? That would be a neat conversation piece, if nothing else.

I can't make up my mind if the performance would be decent or outright sucky. It would probably only be a monobander at any rate.

It's amazing the things the hobby has forgotten.

--Thom
Killer Aircraft One Zeppelin Goes Crash

[KB2WIG]

  " It's amazing the things the hobby has forgotten. "

Yes, it is sad...  so much practical information ends up on the scrap heap of history...  How many can remember loading up the windshield defroster with TTY paper tape holes?     klc

[Steve - WB3HUZ]

I know what you are thinking about Derb. It was called the Johnson Q Antenna system. It was really an impedance matching system. You are thinking of the center insulator for this system. It is not the item pictured in the initial post. The Q system center insulator was shaped like a a cross, like this -|- .

The antenna wires connected to the two opposite ends of one arm of the cross and the feedline to the other two. Short jumpers connected the antenna to the feedline. The feedline was then turned 90 degrees from how we would most often see it connected. And it wasn't just any old feedline connected. They were made from tubing and the spacing was adjustable to effect an impedance match (it was really just an adjustable series stub). Johnson made different length "Q-bars", as they were called, for different bands. The open-wire feedline to the shack was connected at the other end of these Q-bars. The stub or Q-bars matched the antenna feedpoint impedance to the 600 Ohm open-wire line.  The selling point was that the system was more efficient since the line was matched (no mismatch loss).

Johnson came out with this system in the late 30's.

my memory has been jogged. many will forget as I did that ef johnson made antenna parts in the early 30's that used these spreaders. I remember seeing the ads in QST for them. the transposition was exactly so that the wires would not act like a transmission line. They were supposed to radiate.  I think the name "Hi-Q" was used to describe them. They were mostly for directional wire antennas like lazy H's and such for 20 thru 5 meters.

[N3DRB The Derb]

yeh, that's rite. Got some of it right anyways.

I found a 500ft roll of #16 blk thhn insulated wire hiding in a cabinet today. Hmmmm what to do....

[Steve - WB3HUZ]

One of the designs Johnson pushed was a two-element phased array system that would work on two adjacent harmonically related bands (e.g 80&40, 20&10 meters). They called it the Q-beam. They claimed 4 dB gain on the lower band and 6 dB on the higher band. Only one 600 Ohm feeder was needed. I may have to model this thing.

[VE7 Kilohertz]

  " It's amazing the things the hobby has forgotten. "

Yes, it is sad...  so much practical information ends up on the scrap heap of history...  How many can remember loading up the windshield defroster with TTY paper tape holes?     klc

Interesting..the ad doesn't give a phone # or TTY #.

One of the reasons I have ARRL handbooks back to 1941....so much of the things relavent to our hobby today, just aren't published.  Physics hasn't changed (much) ....it's all good stuff. 

cheers
Paul

[KA1ZGC]

How many can remember loading up the windshield defroster with TTY paper tape holes?

I had to explain to an IT guy at one of my last jobs what the stack of punch cards I had at my desk were originally used for.

He didn't beleive me.

--Thom
Kilimanjaro Africa One Zulu Goat Cheese