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A little off topic, but does anyone know?

John P
 

I recently got a couple of Jennings vacuum variable capacitors on eBay, which I hope to use on the magnetic loop antenna I'm building to go with my Bitx-40.

One is missing the threaded rod adjustment shaft. I cannot for the life of me figure out what the thread is. The shaft is 1/4", but the thread count is neither 24 or 28, which would be standard for a 1/4" rod. I tried putting some graphite on it then pressing it on a piece of paper so I could see the thread marks (looks like //////////) and when I count how many I come up in an inch, I get 28, so it's close to that, but not exact. Any help would be appreciated. If anyone knows the specifications, or has a spare, please?let me know.

Thanks
--
John - WA2FZW
Vince Vielhaber
 

Are you sure it's not metric? Measure the distance between threads in mm
to get the pitch. It could be an M6. If the shafts are the same, take
the one you have to the hardware store and try different nuts till you get
it. Either that or find someone with a Thread Detective.

Vince.

I recently got a couple of Jennings vacuum variable capacitors on eBay,
which I hope to use on the magnetic loop antenna I'm building to go with
my Bitx-40.

One is missing the threaded rod adjustment shaft. I cannot for the life of
me figure out what the thread is. The shaft is 1/4", but the thread count
is neither 24 or 28, which would be standard for a 1/4" rod. I tried
putting some graphite on it then pressing it on a piece of paper so I
could see the thread marks (looks like //////////) and when I count how
many I come up in an inch, I get 28, so it's close to that, but not exact.
Any help would be appreciated. If anyone knows the specifications, or has
a spare, please??let me know.

Thanks
--
John - WA2FZW
--
Michigan VHF Corp.

John
 

Hello John,

Do you know where the capacitors were manufactured?

The British Standard Fine (BSF) thread is 1/4" x 26 threads per inch.?

Could it be 6mm coarse, which is 25.4 threads per inch (and slightly smaller in diameter)?

I hope this is of some help.

73,

John G4EDX
Nottingham, England

On 21 July 2017 at 13:52, John P <j.m.price@...> wrote:
I recently got a couple of Jennings vacuum variable capacitors on eBay, which I hope to use on the magnetic loop antenna I'm building to go with my Bitx-40.

One is missing the threaded rod adjustment shaft. I cannot for the life of me figure out what the thread is. The shaft is 1/4", but the thread count is neither 24 or 28, which would be standard for a 1/4" rod. I tried putting some graphite on it then pressing it on a piece of paper so I could see the thread marks (looks like //////////) and when I count how many I come up in an inch, I get 28, so it's close to that, but not exact. Any help would be appreciated. If anyone knows the specifications, or has a spare, please?let me know.

Thanks
--
John - WA2FZW


John P
 

On Fri, Jul 21, 2017 at 06:18 am, Vince Vielhaber wrote:
Are you sure it's not metric? Measure the distance between threads in mm
to get the pitch. It could be an M6. If the shafts are the same, take
the one you have to the hardware store and try different nuts till you get
it. Either that or find someone with a Thread Detective.
Thanks for replying! It measures 0.246" or 6.22mm on the caliper, so definitely 1/4". I think John from England just gave me the answer. Never heard of a thread detective; I'll have to check that out!
?
--
John - WA2FZW
 

?

You could look up the specs on the Jennings catalog. I notice that several of the caps use a UNEF or (ISO) thread standard.


Sent from Yahoo Mail.


On Friday, July 21, 2017 8:52 AM, John P <j.m.price@...> wrote:


I recently got a couple of Jennings vacuum variable capacitors on eBay, which I hope to use on the magnetic loop antenna I'm building to go with my Bitx-40.

One is missing the threaded rod adjustment shaft. I cannot for the life of me figure out what the thread is. The shaft is 1/4", but the thread count is neither 24 or 28, which would be standard for a 1/4" rod. I tried putting some graphite on it then pressing it on a piece of paper so I could see the thread marks (looks like //////////) and when I count how many I come up in an inch, I get 28, so it's close to that, but not exact. Any help would be appreciated. If anyone knows the specifications, or has a spare, please?let me know.

Thanks
--
John - WA2FZW


John P
 

On Fri, Jul 21, 2017 at 06:19 am, John wrote:
The British Standard Fine (BSF) thread is 1/4" x 26 threads per inch.?
I think you've?come up with the answer! I'll have to see if I can find such rods here in the US. If not, any chance you can find me?some there and ship?

?
--
John - WA2FZW
 

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I have been watching those on eBay.? What did you get? ? How much$?

I did not get an answer from a seller, so I forgot about them.

I am staying away from the Russian ones.

Some had too much capacity!? I was looking at 4-7 KV, maybe 400pF?


I got all the parts for the loop.? 2 10' sticks of 3/4 Copper Pipe,? 45 degree Els, and a 10 ft roll of 1/4" copper for the coupling loop.

I am going to cut each 10' into 4 pieces.? Now I need a capacitor?? I got the Els and misc copper fittings on line,? a lot better

price than Home Depot.? I chose the "thinner" 3/4 pipe, it was about $21 a length.


If the diameter is 1/4" (not 6mm) it has to be 1/4-28.?? Go to the hardware store with the cap and test it with a nut?


Mike, WA6ISP


On 7/21/2017 5:52 AM, John P wrote:
I recently got a couple of Jennings vacuum variable capacitors on eBay, which I hope to use on the magnetic loop antenna I'm building to go with my Bitx-40.

One is missing the threaded rod adjustment shaft. I cannot for the life of me figure out what the thread is. The shaft is 1/4", but the thread count is neither 24 or 28, which would be standard for a 1/4" rod. I tried putting some graphite on it then pressing it on a piece of paper so I could see the thread marks (looks like //////////) and when I count how many I come up in an inch, I get 28, so it's close to that, but not exact. Any help would be appreciated. If anyone knows the specifications, or has a spare, please?let me know.

Thanks
--
John - WA2FZW 

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...
Jack Purdum
 

Hi Mike:

A friend and I've each purchased vvc's from Russia (i.e., Ukraine, Russian Federation) and both were perfect and a heck of a deal. Mine is in the 10KV range as I want to also be able to use it with my 100W rig. It will be controlled with an Arduino and small stepper motor for remote tuning.?

I've lost both antennas here to recent tornadoes and just got my EFHW put back up. Even though I have almost 3 acres, a local ordinance named Jane's Law (i.e., the XYL) requires that the antenna be pretty much invisible from the house. The mag loop will be an experiment to see if it is a solution. It will also help with the noise I have here.

Anyway, I wouldn't hesitate to buy a vvc from Russia.

Jack, W8TEE


From: Michael Hagen <motdog@...>
To: [email protected]
Sent: Friday, July 21, 2017 9:32 AM
Subject: Re: [BITX20] A little off topic, but does anyone know?

I have been watching those on eBay.? What did you get? ? How much$?
I did not get an answer from a seller, so I forgot about them.
I am staying away from the Russian ones.
Some had too much capacity!? I was looking at 4-7 KV, maybe 400pF?

I got all the parts for the loop.? 2 10' sticks of 3/4 Copper Pipe,? 45 degree Els, and a 10 ft roll of 1/4" copper for the coupling loop.
I am going to cut each 10' into 4 pieces.? Now I need a capacitor?? I got the Els and misc copper fittings on line,? a lot better
price than Home Depot.? I chose the "thinner" 3/4 pipe, it was about $21 a length.

If the diameter is 1/4" (not 6mm) it has to be 1/4-28.?? Go to the hardware store with the cap and test it with a nut?

Mike, WA6ISP

On 7/21/2017 5:52 AM, John P wrote:
I recently got a couple of Jennings vacuum variable capacitors on eBay, which I hope to use on the magnetic loop antenna I'm building to go with my Bitx-40.

One is missing the threaded rod adjustment shaft. I cannot for the life of me figure out what the thread is. The shaft is 1/4", but the thread count is neither 24 or 28, which would be standard for a 1/4" rod. I tried putting some graphite on it then pressing it on a piece of paper so I could see the thread marks (looks like //////////) and when I count how many I come up in an inch, I get 28, so it's close to that, but not exact. Any help would be appreciated. If anyone knows the specifications, or has a spare, please?let me know.

Thanks
--
John - WA2FZW 

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...



Virus-free.

John P
 

On Fri, Jul 21, 2017 at 06:32 am, Michael Hagen wrote:
I have been watching those on eBay.? What did you get? ? How much$?
Well, I stole them. The seller had no idea what he was selling. Had them advertised as antique radio tubes! Got a pair for $40.?One is complete, but as I said, the other is missing the adjustment rod.

As John G4EDX pointed out above, the British Standard Fine specification is 1/4-26, so it does not have to be 1/4-24 or -28;?didn't have to go to the hardware store to try different nuts; I have quite a collection!
?
--
John - WA2FZW
John P
 

On Fri, Jul 21, 2017 at 06:52 am, Jack Purdum wrote:
a local ordinance named Jane's Law (i.e., the XYL) requires that the antenna be pretty much invisible from the house
Paint it green and hang it in a tree! LOL!
?
--
John - WA2FZW
John
 

Hello John,

Let me know exactly what you need (length, material) and I'll see what I can find. BSF isn't common these days, everybody seems want metric now.

I found this item on ebay;?261467361177?
This comes in cut lengths, maximum 6 inches, mild steel, not plated. Can't vouch for the quality as I've not seen it. Free postage within the UK but I expect it would be expensive across the pond.

73,

John G4EDX

On 21 July 2017 at 14:26, John P <j.m.price@...> wrote:
On Fri, Jul 21, 2017 at 06:19 am, John wrote:
The British Standard Fine (BSF) thread is 1/4" x 26 threads per inch.?
 I think you've?come up with the answer! I'll have to see if I can find such rods here in the US. If not, any chance you can find me?some there and ship?

?
--
John - WA2FZW


Vince Vielhaber
 

$21 a length for 3/4 copper pipe was better than home depot? How much did
home depot want for it? Here (Mich) it's only $15.

Vince.

I am going to cut each 10' into 4 pieces. Now I need a capacitor? I
got the Els and misc copper fittings on line, a lot better

price than Home Depot. I chose the "thinner" 3/4 pipe, it was about $21
a length.
--
Michigan VHF Corp.

John P
 

On Fri, Jul 21, 2017 at 07:09 am, John wrote:
I found this item on ebay;?261467361177?
This comes in cut lengths, maximum 6 inches, mild steel, not plated. Can't vouch for the quality as I've not seen it. Free postage within the UK but I expect it would be expensive across the pond.
Thanks John! I did find a place over there that sells 3' lengths, but this looks like a better deal.
?
--
John - WA2FZW
Steve Black
 

开云体育

Funny how a local ordinance can override federal statute in this particular case. Is it electrical noise or noise from the author of the local ordinance? I have both.:-D Steve kb1chu


On 7/21/2017 9:52 AM, Jack Purdum via Groups.Io wrote:

Hi Mike:

A friend and I've each purchased vvc's from Russia (i.e., Ukraine, Russian Federation) and both were perfect and a heck of a deal. Mine is in the 10KV range as I want to also be able to use it with my 100W rig. It will be controlled with an Arduino and small stepper motor for remote tuning.?

I've lost both antennas here to recent tornadoes and just got my EFHW put back up. Even though I have almost 3 acres, a local ordinance named Jane's Law (i.e., the XYL) requires that the antenna be pretty much invisible from the house. The mag loop will be an experiment to see if it is a solution. It will also help with the noise I have here.

Anyway, I wouldn't hesitate to buy a vvc from Russia.

Jack, W8TEE


From: Michael Hagen <motdog@...>
To: [email protected]
Sent: Friday, July 21, 2017 9:32 AM
Subject: Re: [BITX20] A little off topic, but does anyone know?

I have been watching those on eBay.? What did you get? ? How much$?
I did not get an answer from a seller, so I forgot about them.
I am staying away from the Russian ones.
Some had too much capacity!? I was looking at 4-7 KV, maybe 400pF?

I got all the parts for the loop.? 2 10' sticks of 3/4 Copper Pipe,? 45 degree Els, and a 10 ft roll of 1/4" copper for the coupling loop.
I am going to cut each 10' into 4 pieces.? Now I need a capacitor?? I got the Els and misc copper fittings on line,? a lot better
price than Home Depot.? I chose the "thinner" 3/4 pipe, it was about $21 a length.

If the diameter is 1/4" (not 6mm) it has to be 1/4-28.?? Go to the hardware store with the cap and test it with a nut?

Mike, WA6ISP

On 7/21/2017 5:52 AM, John P wrote:
I recently got a couple of Jennings vacuum variable capacitors on eBay, which I hope to use on the magnetic loop antenna I'm building to go with my Bitx-40.

One is missing the threaded rod adjustment shaft. I cannot for the life of me figure out what the thread is. The shaft is 1/4", but the thread count is neither 24 or 28, which would be standard for a 1/4" rod. I tried putting some graphite on it then pressing it on a piece of paper so I could see the thread marks (looks like //////////) and when I count how many I come up in an inch, I get 28, so it's close to that, but not exact. Any help would be appreciated. If anyone knows the specifications, or has a spare, please?let me know.

Thanks
--
John - WA2FZW 

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...



Virus-free.

 

At $2.10/lft, that's about the going rate for 3/4" M or L types hard temper.?

Grab a 30' roll of 3/4" soft copper tubing for refridgerant line and you'll only pay $1.48/lft. It's easier to bend into shape too.?



On Fri, Jul 21, 2017 at 10:33 AM, Vince Vielhaber <vev@...> wrote:

$21 a length for 3/4 copper pipe was better than home depot?? How much did
home depot want for it?? Here (Mich) it's only $15.

Vince.


> I am going to cut each 10' into 4 pieces.? Now I need a capacitor?? I
> got the Els and misc copper fittings on line,? a lot better
>
> price than Home Depot.? I chose the "thinner" 3/4 pipe, it was about $21
> a length.

--
? ?Michigan VHF Corp.? ?? ?
? ? ? ? ? ? ? ?








--

Andrew Krause
General Class Amateur Radio License: KM4ZJO
andrew.krause@...
(404) 732-2369
Jack Purdum
 

Fortunately, no. Actually, our local power company is pretty good about fixing noise power lines if you complain about it.?

Jack, W8TEE


From: Steve Black via Groups.Io <kb1chu@...>
To: [email protected]
Sent: Friday, July 21, 2017 10:49 AM
Subject: Re: [BITX20] A little off topic, but does anyone know?

Funny how a local ordinance can override federal statute in this particular case. Is it electrical noise or noise from the author of the local ordinance? I have both.:-D Steve kb1chu

On 7/21/2017 9:52 AM, Jack Purdum via Groups.Io wrote:
Hi Mike:

A friend and I've each purchased vvc's from Russia (i.e., Ukraine, Russian Federation) and both were perfect and a heck of a deal. Mine is in the 10KV range as I want to also be able to use it with my 100W rig. It will be controlled with an Arduino and small stepper motor for remote tuning.?

I've lost both antennas here to recent tornadoes and just got my EFHW put back up. Even though I have almost 3 acres, a local ordinance named Jane's Law (i.e., the XYL) requires that the antenna be pretty much invisible from the house. The mag loop will be an experiment to see if it is a solution. It will also help with the noise I have here.

Anyway, I wouldn't hesitate to buy a vvc from Russia.

Jack, W8TEE


From: Michael Hagen <motdog@...>
To: [email protected]
Sent: Friday, July 21, 2017 9:32 AM
Subject: Re: [BITX20] A little off topic, but does anyone know?

I have been watching those on eBay.? What did you get? ? How much$?
I did not get an answer from a seller, so I forgot about them.
I am staying away from the Russian ones.
Some had too much capacity!? I was looking at 4-7 KV, maybe 400pF?

I got all the parts for the loop.? 2 10' sticks of 3/4 Copper Pipe,? 45 degree Els, and a 10 ft roll of 1/4" copper for the coupling loop.
I am going to cut each 10' into 4 pieces.? Now I need a capacitor?? I got the Els and misc copper fittings on line,? a lot better
price than Home Depot.? I chose the "thinner" 3/4 pipe, it was about $21 a length.

If the diameter is 1/4" (not 6mm) it has to be 1/4-28.?? Go to the hardware store with the cap and test it with a nut?

Mike, WA6ISP

On 7/21/2017 5:52 AM, John P wrote:
I recently got a couple of Jennings vacuum variable capacitors on eBay, which I hope to use on the magnetic loop antenna I'm building to go with my Bitx-40.

One is missing the threaded rod adjustment shaft. I cannot for the life of me figure out what the thread is. The shaft is 1/4", but the thread count is neither 24 or 28, which would be standard for a 1/4" rod. I tried putting some graphite on it then pressing it on a piece of paper so I could see the thread marks (looks like //////////) and when I count how many I come up in an inch, I get 28, so it's close to that, but not exact. Any help would be appreciated. If anyone knows the specifications, or has a spare, please?let me know.

Thanks
--
John - WA2FZW 

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...



Virus-free.



Jack Purdum
 

Thought of that, too. There's a mulberry tree that's 40' from the house that is at least 10' in diameter that could hide a 60' beam with a VW bus on top of it and it would be invisible from the house. Still, she'd knows it's there...end of story.

Jack, W8TEE


From: John P <j.m.price@...>
To: [email protected]
Sent: Friday, July 21, 2017 10:04 AM
Subject: Re: [BITX20] A little off topic, but does anyone know?

On Fri, Jul 21, 2017 at 06:52 am, Jack Purdum wrote:
a local ordinance named Jane's Law (i.e., the XYL) requires that the antenna be pretty much invisible from the house
Paint it green and hang it in a tree! LOL!
?
--
John - WA2FZW



Virus-free.

 

I guess your old antenna was up high enough she didn't notice it: ??/g/BITX20/message/24965

Some 28 gauge magnet wire and fishing line into the top of that tree could make for an excellent inverted V or EFHW.
If you put it up at night, nobody would know it's there.
You probably have a grandkid or two that would be quite keen to climb the tree for you.

Jerry, KE7ER



On Fri, Jul 21, 2017 at 09:01 am, Jack Purdum wrote:

Thought of that, too. There's a mulberry tree that's 40' from the house that is at least 10' in diameter that could hide a 60' beam with a VW bus on top of it and it would be invisible from the house. Still, she'd knows it's there...end of story.
?
Jack, W8TEE
Jack Purdum
 

She's okay with the dipole and EFHW that's hiding in the tree, although I haven't replaced the dipole since the storm. However, towers with beams and verticals are out. (She saw one at a friends house and that was that.) She has not seen a mag loop yet...hee, hee, hee...

Jack, W8TEE

From: Jerry Gaffke via Groups.Io <jgaffke@...>
To: [email protected]
Sent: Friday, July 21, 2017 1:56 PM
Subject: Re: [BITX20] A little off topic, but does anyone know?

I guess your old antenna was up high enough she didn't notice it: ??/g/BITX20/message/24965

Some 28 gauge magnet wire and fishing line into the top of that tree could make for an excellent inverted V or EFHW.
If you put it up at night, nobody would know it's there.
You probably have a grandkid or two that would be quite keen to climb the tree for you.

Jerry, KE7ER


On Fri, Jul 21, 2017 at 09:01 am, Jack Purdum wrote:
Thought of that, too. There's a mulberry tree that's 40' from the house that is at least 10' in diameter that could hide a 60' beam with a VW bus on top of it and it would be invisible from the house. Still, she'd knows it's there...end of story.
?
Jack, W8TEE



Virus-free.

John P
 

On Fri, Jul 21, 2017 at 06:19 am, John wrote:
Do you know where the capacitors were manufactured?
?
The British Standard Fine (BSF) thread is 1/4" x 26 threads per inch.?
Well, thanks again John for trying to help, but the BSF threaded rods arrived yesterday, and it turns out that that isn't the right answer either. I'm really starting to think Jennings used a proprietary thread; although, I can't imagine why they would do that.
Have to see if I can find a 6mm coarse bolt and try that. I have my doubts though, as the shaft I have is definitely 1/4" according to 2 sets of calipers.

?
--
John - WA2FZW

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