Cockpit

* User Profile

Welcome, Guest. Please login or register.

Login with username, password and session length

Who's Online

  • *Users: 0
  • *Guests: 52
  • *Total: 52

Our Discord

Author Topic: Ground loop gremlins  (Read 295 times)

Offline fsaviator

  • I am chained to this website!
  • *
  • Posts: 1,328
  • Aviation Enthusiast
    • Boeing 737 Next Generation Simulator
  • First Name: Warren
  • Home Location: Riverview, Florida
Ground loop gremlins
« on: October 08, 2018, 12:46:25 PM »
Hey everyone...  need some help here.  I'm at a standstill until I figure this out - I apologize for the lengthy post but you'll see I had little choice.

I've spent two days trying to isolate what appears to be a ground loop that I noticed when I leaned against my TQ and pedestal.  The annunciators in my firepanel would flicker...  took a bit but figured out the TQ side panel had rubbed paint off and was touching the CDU bay in the front, and pedestal in the back

After much searching I determined that the CPFlight five pin cable going to the pedestal was grounding out to the frame somewhere.

More digging and I isolated it to my CPFLight MCP, and finally after more searching to the serial connection on the MCP.  Apparently one of the pins in the RS232 connector grounds out to the frame! 

The serial cable is connected to USB to serial cable connected to my Main PC WHICH IS OFF.  When I remove the USB from the computer, the ground loop is gone.

Now here is where I need help...

I removed all the connections from the PC to the sim... no cables from the PC to any part of the Sim or even visuals..  only the Power cable and the USB to serial adapter and there is still a ground loop, even when the PC is off.  Unplug the PC and the ground loop is gone.

I assume there must be a short elsewhere, and I should now start unplugging power cables connected to the same circuit to isolate the item then trace down the short?

Thoughts?

I'm so close to being up and flying and now I'm bogged down in this, but I know if I don't fix this, I'll have gremlins loose driving me crazy.
Warren "MTN385"
Florida

http://www.B737NG-SIM.com and https://www.facebook.com/fsaviator on facebook
FSX, Prosim737 Suite, FDS DSTD 2.0 MIP, RevSim Proline TQ, ACE Dual-linked Yokes, Intel 3.5GHz i7-3770K, MSI Z77A-G45, 16GB G.Skill TridentX DDR3-2400, Galaxy GTX670 GC 4GB, OCZ 60GB Vertex 3

Offline fsaviator

  • I am chained to this website!
  • *
  • Posts: 1,328
  • Aviation Enthusiast
    • Boeing 737 Next Generation Simulator
  • First Name: Warren
  • Home Location: Riverview, Florida
[SOLVED] Ground loop gremlins
« Reply #1 on: October 08, 2018, 03:01:02 PM »
I traced the issue down to my MIP power supply.  It's an ATX PS that I modified with terminal blocks to provide +5VDC and +12VDC to my fuse blocks.  As soon as I pulled that out, my frame and PC are no longer "connected".  I wonder if it was because I had it mounted in the shell...

Got it connected back up outside the shell and the issue was resolved.  Just to confirm, I ran a jumper from the ATX PS housing to frame, and the problem was recreated....  the frame and PC were once again "connected", through a USB Hub powered by the PS (which was connected to the PC).

Am I making a big deal of nothing?  I guess once I get everything back together we'll find out if the flickering lights in the Fire panel persist.
Warren "MTN385"
Florida

http://www.B737NG-SIM.com and https://www.facebook.com/fsaviator on facebook
FSX, Prosim737 Suite, FDS DSTD 2.0 MIP, RevSim Proline TQ, ACE Dual-linked Yokes, Intel 3.5GHz i7-3770K, MSI Z77A-G45, 16GB G.Skill TridentX DDR3-2400, Galaxy GTX670 GC 4GB, OCZ 60GB Vertex 3

Offline Trevor Hale

  • Administrator
  • I am chained to this website!
  • *
  • Posts: 3,762
    • Cockpitbuilders.com
  • First Name: Trevor
  • Home Location: New Liskeard, Ontario
Re: Ground loop gremlins
« Reply #2 on: October 08, 2018, 04:49:40 PM »
Great Find warren.  Sometimes these things arent big deals, until they become one.  Glad you found it.
Bob had something similar once, his landing gear would deploy randomly that was a problem LOL.
Trev
Trevor Hale

Owner
http://www.cockpitbuilders.com

Director of Operations
Worldflight Team USA
http://www.worldflightusa.com

VATSIM:

 

FlightSimExpo 2019

FsExpo

COUNTDOWN TO WF2019


WORLDFLIGHT TEAM USA

Will Depart in...

Recent Posts

For Sale: Jetmax 737 TQ - Texas, USA
by MistyBlue
[Today at 02:19:22 PM]
What have you done for your simulator today?
by MistyBlue
[Today at 02:17:28 PM]
FSUIPC 5 Button Limitations
by GyverX
[February 18, 2019, 05:33:55 PM]
Operating System Blues
by Joe Lavery
[February 18, 2019, 02:47:27 PM]
Virtual FO software
by fsaviator
[February 18, 2019, 02:36:20 PM]
Join me on Vatsim Tonight
by Trevor Hale
[February 17, 2019, 01:48:52 PM]
Throttle
by 727737Nut
[February 17, 2019, 09:14:54 AM]
737 NG Throttle Levers
by mickc
[February 17, 2019, 05:02:01 AM]
For sale: A set of faceplate panel for pedestal
by mickc
[February 17, 2019, 05:01:07 AM]
FlyAB Simparts: A new supplier for your OEM needs
by Trevor Hale
[February 16, 2019, 10:51:54 PM]
B737-800 Flight Sim for sale $85,000.00
by Rob_b
[February 16, 2019, 12:47:11 AM]
PC upgrade-build-or buy advice??
by iwik
[February 15, 2019, 06:47:11 PM]
Which Processor i7 - 8700K or i7 - 9700K
by Joe Lavery
[February 15, 2019, 05:39:06 PM]
Anyone seen OEM 737-900 ER Throttle Quadrant?
by Fly_AB
[February 15, 2019, 10:32:18 AM]
For Sale: P&P Opencockpit VHF, Transponder, and ADF
by Fly_AB
[February 15, 2019, 09:08:24 AM]
737 DIY MIP For Sale
by Trevor Hale
[February 14, 2019, 11:03:35 AM]
New supplier for your sim
by Fcoq
[February 14, 2019, 12:18:44 AM]
For Sale Prosim 737 v2.03 License
by mdavenport
[February 12, 2019, 04:00:00 PM]
Complete 737-800 cockpit - moving sale
by navymustang
[February 10, 2019, 12:50:48 PM]
737-800 Arduino X-Plane Build
by kurt-olsson
[February 10, 2019, 09:31:17 AM]
Revolution Simproducts out of business?
by fsaviator
[February 09, 2019, 12:18:30 PM]
For sale: CPFlight MIP737SE
by Fly_AB
[February 08, 2019, 11:29:26 PM]
For sale: Engravity sixpack pairs --- SOLD
by Fly_AB
[February 08, 2019, 08:32:04 PM]
German B738NG Homecockpit-Projekt
by MjTom
[February 08, 2019, 08:00:54 AM]
Updating Navigraph FMC Data - Project Magenta / ProSim
by Trevor Hale
[February 08, 2019, 07:41:50 AM]
737 Demonstrator For Sale
by Trevor Hale
[February 08, 2019, 07:39:34 AM]
Looking for B737NG or A320 SIM for Home Use
by KingAviation
[February 08, 2019, 03:17:35 AM]
Zibo 737 FlightControl Dataref/Commands
by kurt-olsson
[February 05, 2019, 05:34:35 PM]
Wrong hiegth above ground when landing and P3D set for Panel Only
by FredK
[February 05, 2019, 12:58:20 AM]
Flight Control Panel A Side
by kurt-olsson
[February 04, 2019, 04:34:38 PM]