Sign in   |  Join   |  Help
Untitled Page

ARCHIVED FORUM -- March 2012 to February 2022
READ ONLY FORUM

This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022

 

VGA problem

rated by 0 users
This post has 4 Replies | 0 Followers

david707
Top 500 Contributor
Posts 146
OFFLINE
Bronze Member
david707 Posted: Sun, Feb 2 2014 10:04 PM

I am using a PC connected to a BV8-40 using a male to male VGA cable and getting excellent results using 1280x768 (16:10) resolution. For convenience I need to extend the VGA cable by approx 1m, but using either a female to male extension or other cables/couplers, the picture display changes. It is the same format but much smaller and does not fill the screen. Reverting to the original cable all is well.

There is obviously some signal information going missing when using the extensions. Do I require a specific type cable for the purpose?

This is probably not an issue with the TV but any help would be much appreciated.

TWG
Top 75 Contributor
Posts 1,672
OFFLINE
Gold Member
david707
Top 500 Contributor
Posts 146
OFFLINE
Bronze Member

I am using a 7.5m cable from this company:

http://www.vpi.us/pdf/vext-thn-xx-mm.pdf

This cable works fine but annoyingly I underestimated the length required by approx 0.5m. Its all routed under carpet now hence the choice of an extension.

The extension cable is here:

http://www.ebay.co.uk/itm/VGA-M-F-Extension-Cable-for-LCD-Monitor-Projector-1m-/130548469258?pt=UK_Computing_CablesConnectors_RL&hash=item1e654b8e0a#ht_2473wt_1088

and the coupler which I tried with another male to male cable:

http://www.ebay.co.uk/itm/New-15-Pin-SVGA-VGA-Female-to-Female-Gender-Changer-Adapter-Connector-/151182227051?pt=UK_Computing_Sound_Vision_Video_Cables_Adapters&hash=item233329b66b#ht_1925wt_1126

Support for WXGA is not stated on either of these accesories yet there is no suggestion that they are not fully wired. I didnt know all VGA cables were not equal. Wires and pins missing? Why? I thought it was a standard.

Thanks

David

tournedos
Top 10 Contributor
Finland
Posts 7,357
OFFLINE
Bronze Member
Moderator

david707:
Support for WXGA is not stated on either of these accesories yet there is no suggestion that they are not fully wired. I didnt know all VGA cables were not equal. Wires and pins missing? Why? I thought it was a standard.

The cable manufacturers will take every chance to save a wire, since copper costs a lot. The original VGA specification had a few non connected pins. Later, they were first assigned to "monitor ID" function, and eventually to DDC function, which are used by the display controller and the display to negotiate about their capabilities. I strongly suspect that they have been omitted in your extension cable, therefore the display card/driver in your PC select some lower resolution/refresh rate that will be safe for an "unknown" display.

--mika

david707
Top 500 Contributor
Posts 146
OFFLINE
Bronze Member

That explains it! I should have questioned why they were so cheap. I will purchase an extension from the same manufacturer and to the same spec as my long cable.

Thanks

David 

Page 1 of 1 (5 items) | RSS