Date
1 - 12 of 12
K3 - KIO3 RS-232
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kg9hfrank@gmail.com
PSA for the KIO3 board
After fixing several KIO3 boards (RS-232) I found there was a common thread in all that failed. Every ham had bundled the RS-232 cable with the coax cable or (and?) the DC cables to keep them neat. Keep in mind that if a transient comes down your coax or other lines, it can be easily coupled into the RS-232 cable if bundled with them. While I do not have a large tower, I did have a direct hit to a tree that supports my 80 meter loop. Fortunately two Polyphasers did their job. I try to keep like cables bundled with like, but I dont tie them to anything before the AC or Polyphaser protector. My Elecraft cable does not touch any other cables, and goes straight to the laptop. I also grounded the laptop and used a surge protector on the charger cable which is plugged into the A/C all the time. de KG9H
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john ni0k
Motorola's R56 manual addresses this
directly. It specifies the spacing between different types of cables. Induced current surges can cause this type of failure. You may install surge protection on the wires connected to the K3. It is vitally important to bond EVERYTHING in your shack to a common ground. Many forget the computer in the shack... that must be bonded as well. If you have a laptop the only ground point is the locking screw for the VGA connector. YMMV -- kg9hfrank@... via groups.io wrote on 9/7/2022 9:15 AM:73, -de "Curly" John NI0K in rural Debs, MN USA Hamshack Hotline: 6100000271
PSA for the KIO3 board
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Kent Trimble, K9ZTV
Assuming your laptop has a VGA connector with a locking screw, which
none of mine have.
K9ZTV On 9/7/2022 9:38 AM, john ni0k wrote:
If you have a laptop the only ground point is the locking screw for the VGA connector.
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Mike - K8CN
Is it the case that a VGA connector body (metal shell)
would be bonded to the laptop motherboard ground plane (DC return)?
I've never thought to make such a measurement.
Mike, K8CN
From: Elecraft-K3@groups.io <Elecraft-K3@groups.io> on behalf of Kent Trimble, K9ZTV <k9ztv@...>
Sent: Wednesday, September 7, 2022 11:15 AM To: Elecraft-K3@groups.io <Elecraft-K3@groups.io> Subject: Re: [Elecraft-K3] K3 - KIO3 RS-232
CAUTION: This email originated from outside of the University System. Do not click links or open attachments unless you recognize the sender and know the content is safe.
Assuming your laptop has a VGA connector with a locking screw, which none of mine have.
K9ZTV On 9/7/2022 9:38 AM, john ni0k wrote:
If you have a laptop the only ground point is the locking screw for the VGA connector.
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kg9hfrank@gmail.com
NI0K, thanks for your information, if you have the link for R56, it would be a huge addition to this post! Most dont have access to that doc.
Mike, K8CN, I agree most laptops dont have one, you may have to get creative. Remember the laptop ground is an addition, the source if you will, into the KIO3 is the RS-232 cable. Protect that first!
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john ni0k
R56 link: 68P81089E50.book - Motorola_R56.pdf -- kg9hfrank@... via groups.io wrote on 9/7/2022 10:25
AM:73, -de "Curly" John NI0K in rural Debs, MN USA Hamshack Hotline: 6100000271
NI0K, thanks for your information, if you have the link for R56, it would be a huge addition to this post! Most dont have access to that doc.
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David Cutter
Are the USB connectors floating? If not, there are usually 2 or more of these on a laptop and one could be dedicated to this task. Perhaps we should save those old laptops that have better grounding opportunities, eg Lenovo et al.
David G3UNA
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john ni0k
R56 Section 9.9.1.5, page 9-12: Cable Separation and Grouping Within Racks
and Cabinets: Cabling within racks
and cabinets shall be grouped according to function. Garoups are defined
as follows:
Cable
groups within racks and cabinets shall be separated by 2" from other
cable groups. When practical cable groups at or in close
proximity to equipment chassis should be separated by 2" or cross at 90
degree angle. Cable Separation and Grouping
within Cable Trays
-- kg9hfrank@... via groups.io wrote on 9/7/2022 10:25
AM:-J
NI0K, thanks for your information, if you have the link for R56, it would be a huge addition to this post! Most dont have access to that doc.
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KE1F Lou
My 3 station monitors have no singular ground post to connect to my station ground. Lou KE1F On 9/7/2022 15:25, kg9hfrank@...
wrote:
NI0K, thanks for your information, if you have the link for R56, it would be a huge addition to this post! Most dont have access to that doc.
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Jim Brown
On 9/7/2022 8:21 AM, Carter, Michael wrote:
Is it the case that a VGA connector body (metal shell)The shells of D-connectors and USB connectors are required to be chassis ground. In the KIO3, audio I/O have a capacitor between sleeve and chassis, and W4TV has noted that there are small inductors as load or resistors that blow with a strike. There are also 600 ohm resistors as build-out and load in audio I/O, which hasn't been done in pro audio for more than 50 years. It's bad design on the board. Most destructive failures would be prevented by proper grounding and bonding, but many hams have no clue about that. There's an excellent ARRL book by N0AX, to which I contributed, and a slide deck on my website for a talk I've done for west coast ham conventions and to several clubs. k9yc.com/publish.htm 73, Jim K9YC
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kg9hfrank@gmail.com
Jim
toggle quoted messageShow quoted text
Of course I figured I would hear from you Saw your presentation at Shure many years ago I’m the one that runs the EMC MiniSymposium here in Chicago lol Sincerely, Frank Krozel t: 1-630-924-1600 frank@... BSEE, AASEET, FCC Lic.# PG-18-19178, KG9H Electronic Instrument Associates - Central, Inc. ...since 1971 w: www.electronicinstrument.com d/l our linecard at http://www.electronicinstrument.com/lc.pdf
On Sep 7, 2022, at 1:38 PM, Jim Brown <k9yc@...> wrote:
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Jim Brown
Hi Frank,
toggle quoted messageShow quoted text
Yes, I remember those mini-symposiums well -- very useful sessions, some elements of which I have quoted often. 73, Jim
On 9/7/2022 11:59 AM, kg9hfrank@... wrote:
Jim
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