Re: Equipment Interconnect cables
Teflon insulation RG-400 and RG-142 coax jumpers are available here:
73,
Dave, w6de
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Steve via groups.io Sent: 11 November, 2024 19:39 To: [email protected]Subject: Re: [ham-amplifiers] Equipment Interconnect cables On 11/11/2024 10:57 AM, Michael wrote: Holy crap those jumper are over $100 each. Too rich for me. Me, too. (It astounds me how some guys who experimented with ferrite and powdered-iron balun and transformer cores awhile back used so much RG-400 for most of them! Where did they find the cash to buy that much of that schtuff... or did they salvage it from work, like I used to do decades and decades ago? 8-) I used to salvage my RG-142 jumpers from old military test equipment; a length that was a couple feet long was a REAL treasure. These days, I treat all of mine as if they were made of platinum; they even have their own storage box 8-) Steve, K0XP
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Re: Equipment Interconnect cables
Years ago I acquired a quantity of 1/4 inch Heliax. I use RG59 adapters for PL connectors and lightly solder the cable to the tip of the adapter. Screw into the PL connector and solder the center conductor. Works great will last forever.
On 11/11/2024 10:57 AM, Michael wrote:
> Holy crap those jumper are over $100 each. Too rich for me.
Me, too. (It astounds me how some guys who experimented with ferrite and
powdered-iron balun and transformer cores awhile back used so much
RG-400 for most of them! Where did they find the cash to buy that much
of that schtuff... or did they salvage it from work, like I used to do
decades and decades ago? 8-) I used to salvage my RG-142 jumpers from
old military test equipment; a length that was a couple feet long was a
REAL treasure. These days, I treat all of mine as if they were made of
platinum; they even have their own storage box 8-)
Steve, K0XP
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Re: Equipment Interconnect cables
Me, too. (It astounds me how some guys who experimented with ferrite and
powdered-iron balun and transformer cores awhile back used so much
RG-400 for most of them! Where did they find the cash to buy that much
of that schtuff...
?
I have always been lower middle class. There are many hams who have incomes double, triple, or even a lot higher than my own. They can afford to buy the most expensive solutions to setting up a hamshack. So, when something like $108 dollar jumpers are recommended this is reasonable for many hams. I spent my life immersed in my work and not thinking about making more money. I guess I was very lucky in one way. I did not plan for retirement. My civil service job made that plan for me. We have enough income to buy the food we need and keep our home in good repair. I do most of the repairs, but some of them are getting to be outsourced at my age :-)
?
Warning O.T. ! I was also very lucky in marrying a childhood sweetheart with whom I grew up. I was always afraid of height. She started putting up my antennas when she was 10. She put up her last antenna when she was 50. She told me that was the last time she was gong to climb a tree for me. I did not have a problem with that after 40 years. Her antenna work got her a job at Raytheon, where she worked on radar and radio antennas because she had no fear of height. She would go up a mast and just unbolt an array and lower it down for replacement without a problem. I did all the technical work on the ships and submarines and she did all the antenna, disassembly, and assembly of equipment. She got paid the same as myself. Going up those masts was considered worth the pay of an FCC licensed engineer. A ship captain reported us to Raytheon because he saw her kissing me after we had done a successful repair. The supervisor at Raytheon corporate told him that we were married and that calmed the captain down a bit. We were a unusual duo doing repair work on Radar, Radio, and Sonar. Back in the 60s, when we wore Raytheon uniforms. It caused quite a stir on a submarine when they found out that they had a woman aboard on a sea trial. She was not recognized as female when she boarded the boat. She was not recognized until we were eating in the wardroom. The captain about choked on his coffee when he realized she was out for full sea trials. She thought it was funny.
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Re: Equipment Interconnect cables
On 11/11/2024 10:57 AM, Michael wrote: Holy crap those jumper are over $100 each. Too rich for me. Me, too. (It astounds me how some guys who experimented with ferrite and powdered-iron balun and transformer cores awhile back used so much RG-400 for most of them! Where did they find the cash to buy that much of that schtuff... or did they salvage it from work, like I used to do decades and decades ago? 8-) I used to salvage my RG-142 jumpers from old military test equipment; a length that was a couple feet long was a REAL treasure. These days, I treat all of mine as if they were made of platinum; they even have their own storage box 8-) Steve, K0XP
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Re: Equipment Interconnect cables
The problem with RG-142 is that the solid center conductor is
easy to displace when the coax is bent, especially sharp bends,
and particularly short lengths such as less than several feet.
It's best not to bend -142 short jumpers more than necessary. You
can tell when the center conductor is displaced by examining the
center pins in the end: it'll be offset on one end compared to the
other. (This is especially obvious when BNC or SMA, the most
common connectors used with -142, are used.) Otherwise, -142 is a
good coax and readily withstands high power.
Steve, K0XP
On 11/11/2024 10:44 AM, Dave w6de
wrote:
Correction
to my previous post.?
I do not use RG-400 jumpers, I use RG-142 coax
jumpers.
Both
RG-400 and RG-142 have similar specs with the exception of
RG-142 has a solid center conductor and RG-400 has a
stranded center conductor.?
I find the flexibility of the center conductor RG-142 to be
suitable for short connections in the shack.?
If I were to make a tightly wound choke RG-400 would
be the appropriate choice.
?
73,
Dave,
w6de
?
?
?
I
buy RG-400 jumpers for all my inside the shack
interconnections.?
Entering the shack, I have a mix of N connectors for
Heliax LDF4 Superflex and PL-259 connectors for RG-213 coax
for antenna connections/terminations from the outside
antennas.?
When I buy the RG-400 jumpers I specify the cable
connectors for each end to keep from using adapters inside
the shack.
?
73,
Dave,
w6de
?
?
Yes that RG-400 is great and can make
sharp bends if need be.
?
On Mon, Nov 11, 2024 at 1:58?AM desmond
auld GI0UTE via <desauld=[email protected]>
wrote:
I use rg400 coax. Same size as rg58,
but teflon insulated and ok for 3kw, or even more on
ssb. Not cheap... Thanks des.?
--
See my QRZ.com page at
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Re: Equipment Interconnect cables
Holy crap those jumper are over $100 each. Too rich for me. I will stick with RG8X and my stock of PL-259s. This has worked for me many years now. I realize that it should not be used for 1500 watts that has any VSWR on it. My VSWR on my two antennas range from 1.2 to 1.6 on a trapped 75 meter dipole. Those connections are all done with something that looks like RG8 but has some other number on it.?
?
I would need jumpers for my VSWR meter and amplifier. I think that comes to 4 jumpers. That would be over $400 dollars from DX Engineering. I know that I am not the only one using RG8X for 1500 watts. My closest neighbor ham is using it.?
?
I also have an antenna switch that may have up to a 1.6 to 1 VSWR on it. It is wired with this RG8 looking stuff. I also use the PL-259 quick disconnects adapters. This makes it easy to pull the antenna connections when a storm is coming.?
?
I would seriously like to hear if there is a reason why I should not use RG8X the way I am using it. I am always open to ideas and opinions. I fully realize that my own understanding of RF is quite limited. I have worked in design of devices that did not carry RF and were low power low frequency stuff limited to 4 mhz.?
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Re: Equipment Interconnect cables
Correction to my previous post.?
I do not use RG-400 jumpers, I use RG-142 coax jumpers.
Both RG-400 and RG-142 have similar specs with the exception of RG-142 has a solid center conductor
and RG-400 has a stranded center conductor.?
I find the flexibility of the center conductor RG-142 to be suitable for short connections in the shack.?
If I were to make a tightly wound choke RG-400 would be the appropriate choice.
?
73,
Dave, w6de
?
?
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From: [email protected] <[email protected]>
On Behalf Of Dave w6de via groups.io
Sent: 11 November, 2024 18:09
To: [email protected]
Subject: Re: [ham-amplifiers] Equipment Interconnect cables
?
I buy RG-400 jumpers for all my inside the shack interconnections.?
Entering the shack, I have a mix of N connectors for Heliax LDF4 Superflex and PL-259 connectors for RG-213 coax for antenna connections/terminations from the outside antennas.?
When I buy the RG-400 jumpers I specify the cable connectors for each end to keep from using adapters inside the shack.
?
73,
Dave, w6de
?
?
Yes that RG-400 is great and can make sharp bends if need be.
?
On Mon, Nov 11, 2024 at 1:58?AM desmond auld GI0UTE via <desauld=[email protected]> wrote:
I use rg400 coax. Same size as rg58, but teflon insulated and ok for 3kw, or even more on ssb. Not cheap... Thanks des.?
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Re: Equipment Interconnect cables
Lots of premade RG-400 cables are at DXE ¨C like this:
? Search for RG-400 ? 73 Tim K3LR @ DXE HQ ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Dave w6de
Sent: Monday, November 11, 2024 1:09 PM
To: [email protected]
Subject: Re: [ham-amplifiers] Equipment Interconnect cables? I buy RG-400 jumpers for all my inside the shack interconnections.? Entering the shack, I have a mix of N connectors for Heliax LDF4 Superflex and PL-259 connectors for RG-213 coax for antenna connections/terminations from the outside antennas.? When I buy the RG-400 jumpers I specify the cable connectors for each end to keep from using adapters inside the shack. ? 73, Dave, w6de ? ? Yes that RG-400 is great and can make sharp bends if need be. ? On Mon, Nov 11, 2024 at 1:58?AM desmond auld GI0UTE via <desauld=[email protected]> wrote: I use rg400 coax. Same size as rg58, but teflon insulated and ok for 3kw, or even more on ssb. Not cheap... Thanks des.?
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Re: Equipment Interconnect cables
I buy RG-400 jumpers for all
my inside the shack interconnections.?
Entering the shack, I have a mix of N connectors for Heliax LDF4 Superflex and PL-259 connectors for RG-213 coax for antenna connections/terminations from the outside antennas.?
When I buy the RG-400 jumpers I specify the cable connectors for each end to keep from using adapters inside the shack.
?
73,
Dave, w6de
?
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From: [email protected] <[email protected]>
On Behalf Of Bob via groups.io
Sent: 11 November, 2024 12:32
To: [email protected]
Subject: Re: [ham-amplifiers] Equipment Interconnect cables
?
Yes that RG-400 is great and can make sharp bends if need be.
?
On Mon, Nov 11, 2024 at 1:58?AM desmond auld GI0UTE via <desauld=[email protected]> wrote:
I use rg400 coax. Same size as rg58, but teflon insulated and ok for 3kw, or even more on ssb. Not cheap... Thanks des.?
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Re: Equipment Interconnect cables
Yes that RG-400 is great and can make sharp bends if need be. Bob W4JFA
On Mon, Nov 11, 2024 at 1:58?AM desmond auld GI0UTE via <desauld= [email protected]> wrote: I use rg400 coax. Same size as rg58, but teflon insulated and ok for 3kw, or even more on ssb. Not cheap... Thanks des.?
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Re: Equipment Interconnect cables
I use rg400 coax. Same size as rg58, but teflon insulated and ok for 3kw, or even more on ssb. Not cheap... Thanks des.?
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Re: the WORST ham built amplifier?
I only ever heard Seymour on 20m.? He was a real character.? ?He was stupid loud here, with his yagi pointed my way.
Those mile long leads will screw up the coil values a bunch.... on those depicted tuned inputs.
?
56% eff isn't good at all.? ?You shoulda been able to get 68% eff on? 160-40m.? ?I'm assuming? your plate current meter, HV meter, wattmeter are all? calibrated ??
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Re: Equipment Interconnect cables
RG8X might become limp with 1.5 kw CXR /? data modes, FT-8 / FM.?
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Re: Equipment Interconnect cables
I have used RG8X for years without a problem. They are all short and losses immeasurable. The cables out to my antennas from the shack are all RG8 or something like that. Mine have handled 1500 watts just fine. It might not be fine if they were not all into 50 ohm loads. I have an RG8X jumper to my tuner and that is tuned at low power. When 1500 watts hits this RG8X it has a 50 ohm match. I have a neighbor who does the same thing as myself with interconnects with his amplifier, transceiver, VSWR meter, and tuner.?
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Equipment Interconnect cables
Hello,
?
In HF service, when running interconnect coax cables from an amplifier outbound, I have always used RG-213 or equivalent from the amp to whatever accessories I was using at the time such as a monitor scope, power meter, ATU, etc. then on to the antenna. Since the interconnect cabling are usually very short lengths, is it acceptable today to use RG-8X for this when running high power or is it standard practice to use the heavier coax?
?
73,
Garry
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Re: TenTec Centurion HV arc to ground
If you have any teflon sleeving, put an inch length over the wire
where it goes through the grommet. If you only have teflon sheet,
cut an inch square and wrap it around the wire through the
grommet. If you don't have any teflon, use plastic bag but I'd be
wary of plastic. I've never used it in this manner but some
plastics break down really easily in the presence of high voltage.
0.01"-thick teflon withstands 1900 VDC, so a double or triple-wrap
of sheet would easily work. I've used 0.019" teflon sheet to build
HV bypass capacitors for the old AM-6154/6155 amplifiers before.
Steve, K0XP
On 11/9/2024 9:26 AM, Robin Midgett via
groups.io wrote:
Thanks
Jim, I agree with your assessment. I replaced the feed
through with a rubber grommet?and soldered the HV wire
directly to the glitch resistor. That seems to work fine
business.
Thanks,
Robin Midgett K4IDC
That's caused by....'surface creep'..... which will also
depend on any dust/gunk / fluff sitting on the insulator.?
?The insulator can be cleaned up. The easy fix is to put a
small piece of plastic sheet (with a hole in it). ..before
the arced insulator is installed.? That will increase the
leakage path by a bunch. ( plastic goes between the
insulator and metal side wall)...so the hole in the plastic
is just big enough....then the lip of the insulator sits on
the plastic sheeting.? ? ?That or replace with a longer
feedthrough HV connector, or use a feedthrough insulator ( 2
x piece type)...that is of the serrated type....which will
also increase the leakage path by a bunch.?
--
See my QRZ.com page at
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Re: TenTec Centurion HV arc to ground
Thanks for the kind offer, Tom. A trusted friend and amp builder suggested?a simpler fix..toss the feed through & replace it with a rubber grommet, solder the wire directly to the glitch resistor. That's what I did & it seems to be a good solution so far.
Thanks,
Robin Midgett K4IDC
Robin- I may have a longer ceramic insulator that would fit your needs. Tell me how long it should be and I will check the junk box.
Tom K0SN?
On Thu, Nov 7, 2024 at 6:58?PM Robin Midgett via <RobinK4IDC= [email protected]> wrote: Yes, these are the notions I've had about the remedy; maybe make an insulator from a solid rod of fiberglass or Teflon with a recess in one end to surround the bolt/nut/solder lug. Thanks Eric!
Thanks,
Robin Midgett K4IDC
I can't tell if the break-down happened because of a defect in the insulator, or if corona from a sharp edge degraded the insulator.? Either way, the insulator should be replaced as it will be impossible to get rid of the carbon track on the insulator.?
There is quite a lot of bolt sticking out of the top of the insulator.? If one can be found, a taller insulator, using the same length bolt, would be a good idea.
Eric WB6TIX
On Thu, Nov 7, 2024 at 6:10?PM Robin Midgett via <RobinK4IDC= [email protected]> wrote:
I'd like to know if any of?you have suggestions as to what caused this HV arc to chassis and hopefully, what to do to prevent it in the?future. Amp is a TenTec Centurion. It was at idle when the arc happened; no RF applied. The glitch resistor took the brunt of the discharge, thank goodness. I've replaced it,?even though the original still?measured the?correct?resistance, it was visually damaged. The event spooked me...new pair of 3-500Z tubes was in the amp; no apparent?damage. The insulator appears to be made of fiberglass. The glitch resistor is on the opposite side of this aluminum panel. The HV feeds through from the resistor via the machine screw. Any thoughts?
Thanks,
Robin Midgett K4IDC
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Re: TenTec Centurion HV arc to ground
Thanks Jim, I agree with your assessment. I replaced the feed through with a rubber grommet?and soldered the HV wire directly to the glitch resistor. That seems to work fine business.
Thanks,
Robin Midgett K4IDC
That's caused by....'surface creep'..... which will also depend on any dust/gunk / fluff sitting on the insulator.? ?The insulator can be cleaned up. The easy fix is to put a small piece of plastic sheet (with a hole in it). ..before the arced insulator is installed.? That will increase the leakage path by a bunch. ( plastic goes between the insulator and metal side wall)...so the hole in the plastic is just big enough....then the lip of the insulator sits on the plastic sheeting.? ? ?That or replace with a longer feedthrough HV connector, or use a feedthrough insulator ( 2 x piece type)...that is of the serrated type....which will also increase the leakage path by a bunch.?
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Bob
Robin Midgett